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Sharma, Amit. "Penetration, pressure drop, and wicking characteristics of NIOSH certified P-100 and P-95 filters under heavy DOP loading." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1365.
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Thesis (M.S.)--West Virginia University, 2000.<br>Title from document title page. Document formatted into pages; contains xii, 233 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 125-128).
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Tousi-Ardakani, Saied. "Numerical investigation of particle collection in electrically enhanced fibrous filters /." Access abstract and link to full text, 1986. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/8702930.
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Tsang, Chang Ming. "Analysis of pleated air filters using computational fluid dynamics." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ29434.pdf.
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Butler, Jessica Caroline Curtis Patricia A. "The effects of electrostatic polarization ultra-violet light filters on the bioaerosols of a commercial broiler processing plant hang room." Auburn, Ala., 2009. http://hdl.handle.net/10415/2010.
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Kennedy, Daniel Mabry Tatarchuk Bruce J. "Fuel cell cathode air filters methodologies for design and optimization /." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2006%20Fall/Theses/KENNEDY_DANIEL_34.pdf.
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Nordstrom, Jeanne McDonald 1957. "The utility of using matched weight PVC filters during air sampling for particulates." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276824.
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Matched weight polyvinyl chloride (PVC) filters are currently available for use in total dust air sampling. This paper studies the utility of employing two superimposed filters in a cassette. Cassettes containing "paired" PVC filters were employed, in the same way matched weight filters would be used, during side by side sampling studies with cassettes housing single PVC filters, to determine whether the presence of two filters in a cassette presented problems during sampling. The effects of dust type, particle breakthrough, moisture concentration, and increased pressure drop from the addition of a second filter were studied. The presence of static electricity between filter pairs was also noted. Under recommended loading conditions "paired" filters seemed to perform as well as single filters in all aspects studied. Due to large filter weight variations found within individual batches of PVC filters, randomly selected filter pairs should not be used as actual matched weight filters.
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Oh, Seung-Min. "Nonlinear Estimation for Vision-Based Air-to-Air Tracking." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19882.
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Unmanned aerial vehicles (UAV's) have been the focus of significant research interest in both military and commercial areas since they have a variety of practical applications including reconnaissance, surveillance, target acquisition, search and rescue, patrolling, real-time monitoring, and mapping, to name a few. To increase the autonomy and the capability of these UAV's and thus to reduce the workload of human operators, typical autonomous UAV's are usually equipped with both a navigation system and a tracking system. The navigation system provides high-rate ownship states (typically ownship inertial position, inertial velocity, and attitude) that are directly used in the autopilot system, and the tracking system provides low-rate target tracking states (typically target relative position and velocity with respect to the ownship). Target states in the global frame can be obtained by adding the ownship states and the target tracking states. The data estimated from this combination of the navigation system and the tracking system provide key information for the design of most UAV guidance laws, control command generation, trajectory generation, and path planning.
As a baseline system that estimates ownship states, an integrated navigation system is designed by using an extended Kalman filter (EKF) with sequential measurement updates. In order to effectively fuse various sources of aiding sensor information, the sequential measurement update algorithm is introduced in the design of the integrated navigation system with the objective of being implemented in low-cost autonomous UAV's. Since estimated state accuracy using a low-cost, MEMS-based IMU degrades with time, several absolute (low update rate but bounded error in time) sensors, including the GPS receiver, the magnetometer, and the altimeter, can compensate for time-degrading errors. In this work, the sequential measurement update algorithm in smaller vectors and matrices is capable of providing a convenient framework for fusing the many sources of information in the design of integrated navigation systems. In this framework, several aiding sensor measurements with different size and update rates are easily fused with basic high-rate IMU processing.
In order to provide a new mechanism that estimates ownship states, a new nonlinear filtering framework, called the unscented Kalman filter (UKF) with sequential measurement updates, is developed and applied to the design of a new integrated navigation system. The UKF is known to be more accurate and convenient to use with a slightly higher computational cost. This filter provides at least second-order accuracy by approximating Gaussian distributions rather than arbitrary nonlinear functions. This is compared to the first-order accuracy of the well-known EKF based on linearization. In addition, the step of computing the often troublesome Jacobian matrices, always required in the design of an integrated navigation system using the EKF, is eliminated. Furthermore, by employing the concept of sequential measurement updates in the UKF, we can add the advantages of sequential measurement update strategy such as easy compensation of sensor latency, easy fusion of multi-sensors, and easy addition and subtraction of new sensors while maintaining those of the standard UKF such as accurate estimation and removal of Jacobian matrices. Simulation results show better performance of the UKF-based navigation system than the EKF-based system since the UKF-based system is more robust to initial accelerometer and rate gyro biases and more accurate in terms of reducing transient peaks and steady-state errors in ownship state estimation.
In order to estimate target tracking states or target kinematics, a new vision-based tracking system is designed by using a UKF in the scenario of three-dimensional air-to-air tracking. The tracking system can estimate not only the target tracking states but also several target characteristics including target size and acceleration. By introducing the UKF, the new vision-based tracking system presents good estimation performance by overcoming the highly nonlinear characteristics of the problem with a relatively simplified formulation. Moreover, the computational step of messy Jacobian matrices involved in the target acceleration dynamics and angular measurements is removed.
A new particle filtering framework, called an extended marginalized particle filter (EMPF), is developed and applied to the design of a new vision-based tracking system. In this work, only three position components with vision measurements are solved in particle filtering part by applying Rao-Blackwellization or marginalization approach, and the other dynamics, including the target nonlinear acceleration model, with Gaussian noise are effectively handled by using the UKF. Since vision information can be better represented by probabilistic measurements and the EMPF framework can be easily extended to handle this type of measurements, better performance in estimating target tracking states will be achieved by directly incorporating non-Gaussian, probabilistic vision information as the measurement inputs to the vision-based tracking system in the EMPF framework.
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Martin, Tifenn. "Air-Filled Substrate Integrated Waveguide (AFSIW) Filters and multiplexers for space application." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0391.
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L'émergence de nouvelles applications micro-ondes et millimétriques dans les secteurs de l'automobile et des communications, y compris l'Internet des objets (IoT), la cinquième génération de mobile (5G) et le nouvel espace, nécessite le développement de nouvelles technologies alternatives offrant un compromis approprié en termes de taille, de poids, de puissance et de coût (SWaP-C). Ce changement de paradigme est essentiellement dû à l'augmentation du débit de données, conduisant à la croissance des différentes bandes passantes. Étant donné qu'un nombre de plus en plus important de systèmes sont en concurrences pour l'occupation du spectre fréquentiel, la communauté des hyperfréquences est poussée à développer de nouveaux systèmes innovants à des fréquences plus élevées avec une efficacité accrue et un degré d’intégration élevé.Ce changement de paradigme a fortement stimulé le développement de systèmes micro-ondes et millimétriques à faible coût, à haute performance, hautement intégrés, compacts et pouvant être produits en masse. Au coeur d'un système, les filtres micro-ondes et millimétriques sont des dispositifs essentiels permettant de sélectionner l'information utile. Les filtres à faibles pertes sont très recherchés dans les circuits d'émission et de réception pour obtenir un rendement élevé et un faible niveau de rapport signal à bruit. La façon conventionnelle d'obtenir de faibles pertes est d'utiliser des résonateurs à haut facteur de qualité. Pour la plupart des applications à haute performance, la technologie des guides d'ondes rectangulaires (RWG) est utilisée pour être conforme aux spécifications sévères requises par l'industrie. Néanmoins, cette technologie devient prohibitive en termes de coût lorsqu'une production de masse est nécessaire. Pour réduire le coût de ces composants, l'utilisation de la technologie émergente des guides d'ondes intégrés au substrat (SIW) a été proposée. Cette technologie bénéficie d’un faible coût de fabrication et est facilement intégrable dans un système basé sur des circuits imprimés. La technologie SIW est une bonne candidate pour les applications qui nécessitant un faible coût avec des performances électriques moyennes, mais pour les applications de hautes performances, comme le nouvel espace, les performances atteintes ne sont pas conformes aux spécifications demandées, ce qui rend l'implémentation de la technologie SIW restrictive pour les applications haute performance.Récemment, le guide d'ondes intégré au substrat rempli d'air (AFSIW), basé sur les procédés standards de circuit imprimé multicouche (PCB), semblerait répondre aux exigences des applications de constellation de satellites, car il offre un compromis entre les technologies classiques RWG et SIW. Cette structure vise à réduire considérablement les pertes d'insertion du milieu de propagation, tout en maintenant le fort aspect d'intégration à faible coût. C'est donc une bonne candidate pour la future génération de charges utiles de satellites.Compte tenu du contexte présenté, les travaux menés au cours de cette thèse de doctorat ont été orientés vers la mise en oeuvre de la technologie AFSIW pour les nouvelles applications spatiales. Une attention particulière a été accordée à la proposition, à l'analyse, au développement et à la mise en oeuvre de concepts novateurs et originaux pour les fonctions de filtrage hyperfréquence. Le travail proposé est basé sur la théorie classique des guides d'ondes en tirant parti des procédés de fabrication standards des circuits imprimés pour permettre le développement de filtres et de multiplexeurs répondant aux spécifications des applications spatiales.Cette thèse de doctorat met en lumière les dernières avancées réalisées dans le développement de filtres hyperfréquences et de multiplexeurs utilisant la technologie AFSIW. Elle détaille, en partant des idées de départ, des démonstrations théoriques, des simulations et des validations expérimentales avec les prototypes fabriqués. [...]<br>The emergence of novel microwave and millimeter wave applications in the automotive and communication sectors including the internet of things (IoT), the fifth generation of mobile (5G), and the new space, require the development of new alternative technologies providing a suitable tradeoff in terms of size, weight, power, and cost (SWaP C). This change of paradigm is essentially due to the increase of data rate, leading to the growth of bandwidth. As a substantially increasing number of systems are competing for frequency spectrum occupancy, the microwave community is pushed to develop new innovative systems at higher frequency with an increased efficiency.This change of paradigm has highly stimulated the development of low cost, high performance, highly integrated, compact, and mass producible microwave and millimeter wave systems. At the heart of a system, microwave and millimeter wave filters are essential devices allowing to select the desired information. Low loss filters are highly desired in transmitter and receiver circuits to achieve high efficiency and low noise figures. The conventional way to achieve low loss performance is to use high quality factor resonators. For most high performance applications, the air-filled rectangular waveguide (RWG) technology is used to comply with the severe specifications requested by the industry. Nevertheless, this technology becomes prohibitive in terms of cost where a mass production is needed. To reduce the cost of such components, the use of the so called substrate integrated waveguide (SIW) emerging technology has been proposed. This technology benefits from low cost and highly integrated properties. The SIW technology is a good candidate for application that needs low cost with medium insertion loss, but for high performance applications, such as the emerging new space, the achieved performances are not compliant with the severe specifications, making the implementation of the SIW technology for high performance applications restrictive.Recently, the alternative air filled substrate integrated waveguide (AFSIW), based on multilayer printed circuit board (PCB) is expected to fulfill satellite constellation application requirements as it offers a compromise between the conventional RWG and SIW technologies. This structure aims to dramatically reduce the insertion loss of the propagation medium, while maintaining the high integration and low cost aspect. Hence making it a potential good candidate for future generation of satellite payloads.Taking into consideration the presented context, the work carried out during this Ph.D. thesis has been led towards the implementation of the AFSIW for the new space applications. A particular attention has been given to the proposal, analysis, development, and implementation of innovative and original concepts for microwave filtering functions. The proposed work is based on the classic waveguide theory taking advantage of the standard PCB process to allow the development of improved and novel filters and multiplexer for space applications.This Ph.D. thesis highlights the last advances made on the development of microwave filters and multiplexer using the AFSIW technology. This includes the starting ideas, theoretical demonstrations, simulations, and experimental validations with fabricated prototypes. The results of this work are promising and demonstrate the relevance of the technology for its implementation in future satellite payload systems. In fact, a sub system of a satellite payload has been developed in this thesis to answer the need of the European Space Agency (ESA) and the Centre National d’Études Spatiales (CNES). The demonstrated concepts gained from this thesis can be considered as a good base to further develop and popularize the AFSIW technology not only for space applications but also for ground systems
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Kornelius, Gerrit. "The design of electrostatically augmented moving bed granular gas filters." Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-05052005-095030/.
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Kruger, Abraham J. "The impact of filter loading on residential hvac performance." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50344.
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Buildings are the primary user of energy in the USA. Within homes, the heating, ventilation, and air condition (HVAC) system is the largest energy consumer. This study: (i) developed a new methodology for simulating filter loading in-situ; (ii) observed the impact of filter loading on AC performance in-situ; and (iii) provided a greater understanding of when a filter is “dirty” and should be replaced. Six central AC systems in the Atlanta metro-region were evaluated. Filter loading was simulated by installing the TrueFlow® airflow metering device and partially taping off the face at 3 different increments. This resulted in measurements at 5 discrete static pressures (no filter, TrueFlow, TrueFlow Taped one, TrueFlow Taped two, and TrueFlow Taped three). The pilot study found that as filter pressure drop increased, airflow rates generally decreased, resulting in higher differences in temperature across the evaporator coil (∆T). There was no observed correlation between absolute humidity across the evaporator coil and either filter pressure drop or system airflow. Overall, as airflow decreased so did sensible, latent, and total capacity. This research can inform decisions about filter replacement and be used to evaluate computer simulation models of HVAC performance.
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Greenshields, Christopher John. "Fast brittle fracture of water/air pressurised plastic pipes." Thesis, Imperial College London, 1995. http://hdl.handle.net/10044/1/8690.
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Ali, Salah Taofeek. "The motion of air cavities in water filled pipes." Thesis, University of Strathclyde, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305002.
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Maddineni, Ajay Kumar. "Particle filtration behaviour of oil-treated fibrous air filters for automotive engine intake application." Thesis, IIT Delhi, 2018. http://eprint.iitd.ac.in:80//handle/2074/8030.
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Bojdo, Nicholas Michael. "Rotorcraft engine air particle separation." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/rotorcraft-engine-air-particle-separation(6c4c7788-1244-45b7-b35e-acc9ae54cacd).html.
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The present work draws together all current literature on particle separating devices and presents a review of the current research on rotor downwash-induced dust clouds. There are three types of particle separating device: vortex tube separators; inlet barrier filters; and inlet particle separators. Of the three, the latter has the longest development history; the former two are relatively new retrofit technologies. Consequently, the latter is well-represented in the literature, especially by computational fluid dynamics simulations, whereas the other two technologies, with specific application to rotorcraft, are found to be lacking in theoretical or numerical analyses. Due to their growing attendance on many rotorcraft currently in operation, they are selected for deeper investigation in the present work.The inlet barrier filter comprises a pleated filter element through which engine bound air flows, permitting the capture of particles. The filter is pleated to increase its surface area, which reduces the pressure loss and increases the mass retention capability. As particles are captured, the filter's particle removal rate increases at the expense of pressure loss. The act of pleating introduces a secondary source of pressure loss, which gives rise to an optimum pleat shape for minimum pressure drop. Another optimum shape exists for maximum mass retention. The two optimum points however are not aligned. In the design of inlet barrier filters both factors are important. The present work proposes a new method for designing and analysing barrier filters. It is found that increasing the filter area by 20% increases cycle life by 46%. The inherent inertial separation ability of side-facing intakes decreases as particles become finer; for the same fine sand, forward-facing intakes ingest 30% less particulate than side-facing intakes. Knowledge of ingestion rates affords the prediction of filter endurance. A filter for one helicopter is predicted to last 8.5 minutes in a cloud of 0.5 grams of dust per cubic metre, before the pressure loss reaches 3000 Pascals. This equates to 22 dust landings.An analytical model is adapted to determine the performance of vortex tube separators for rotorcraft engine protection. Vortex tubes spin particles to the periphery by a helical vane, whose pitch is found to be the main agent of efficacy. In order to remove particles a scavenge flow must be enacted, which draws a percentage of the inlet flow. This is also common to the inlet particle separator. Results generated from vortex tube theory, and data taken from literature on inlet particle separators permit a comparison of the three devices. The vortex tube separators are found to achieve the lowest pressure drop, while the barrier filters exhibit the highest particle removal rate. The inlet particle separator creates the lowest drag. The barrier filter and vortex tube separators are much superior to the inlet particle separator in improving the engine lifetime, based on erosion by uncaptured particles. The erosion rate predicted when vortex tube separators are used is two times that of a barrier filter, however the latter experiences a temporal (but recoverable post-cleaning) loss of approximately 1% power.
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Hill, Barry Keith. "Field portable X-Ray fluorescence for rapid analysis Of titanium dioxide on air filters." Thesis, University of Iowa, 2012. https://ir.uiowa.edu/etd/3312.
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Field portable x-ray fluorescence (FPXRF) was evaluated as a method for screening titanium dioxide (TiO2) on air filters. Mixed cellulose ester (MCE) and polycarbonate (PC) filter types were compared to gravimetric filters to determine if there was a benefit of using one over the other during FPXRF analysis. No significant difference (p-value = 0.92) was found between MCE and PC filters for FPXRF. MCE filters had a higher coefficient of determination (R2 = 0.97) with the FPXRF analyzer than the PC filters (R2 = 0.70) when compared to gravimetric filter results. The limit of detection (LOD) and limit of quantitation (LOQ) of the FPXRF analyzer were determined through the analysis of blank filters and filters with low levels of TiO2 analyte. The LOD for TiO2 using filter blanks was 7.3 μg/filter, and 25 μg/filter with low levels of TiO2 analyte. The LOQ was 12.8 μg/filter determined with filter blanks, and from the low level analyte samples was 0.82 μg/filter. Filter samples were collected at varying TiO2 concentrations and submitted to FPXRF and inductively couple plasma - mass spectrometry (ICP-MS) analysis. Linear regression was used to determine the relationship between the two methods for TiO2 assessment. A high coefficient of determination (R2 = 0.90) was found between FPXRF and ICP-MS at lower TiO2 concentrations while a low coefficient of determination (R2 = 0.24) was shown for the high TiO2 concentrations. Statistical analysis was used to determine the overall accuracy of the FPXRF method. The FPXRF method did not meet the NIOSH accuracy requirements to be considered an acceptable method; however there were unexplained anomalies within the ICP-MS data.
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Luna, Eric Amor Tatarchuk Bruce J. "Improvement of indoor air quality through the development of polymeric microfibrous material." Auburn, Ala., 2009. http://hdl.handle.net/10415/1997.
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Gregg, Andrea. "The application of nanofibrous membranes with antimicrobial agents as filters." Kansas State University, 2010. http://hdl.handle.net/2097/6822.
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Master of Science<br>Department of Architectural Engineering and Construction Science<br>Julia A. Keen<br>Nanofibers are classified as fibers less than 1 micrometer in diameter. These fibers can be layered to form nanofibrous membranes, and these membranes offer great potential in the filtration industry. The membranes' smaller fiber diameters and pore sizes permit such filters to filter out more and smaller particulate. Additionally, antimicrobial agents can be incorporated into the membrane to inhibit fungal and bacterial growth on the membrane’s surface. This report evaluates nanofibrous membranes with antimicrobial agents and their potential in two specific locations: cleanrooms and protective environment rooms, where bacterial and fungal growth would have a detrimental effect on the process or occupant of the space.
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Viktorin, Michal. "Filtrace vzduchu v systémech vzduchotechniky." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-394044.
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The diploma thesis is divided into three parts, analysis of the topic and the chosen method of solutions, application to specified building and experimental solutions and data processing The first part is theoretical. It is about air filtration in terms of normative and legal requirements and variants of technical solutions for air filtration. In the second part there are two technical solutions for HVAC systems for plastic surgery. The third part is experimental. It is the measurement of the number of particles in the air in the operating room and the evaluation of the measurement.
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Alarfaj, Ayman M. A. "Validation of Low Resistance Filters for Gas/Vapour Sampling." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4257.
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Traditional occupational hygiene assessment of occupational exposures to organic gases and vapours rely on low flow (<200 ml/min) NIOSH sorbent tubes. This work investigates 3M charcoal filter media (JK50 and JK40, 3M, Inc.) for collection and analysis of organic vapours across 0.1 ¿ 5 l/min. To enable this work, a custom exposure facility was constructed and validated within which organic analyte gas/vapour concentrations could be introduced at known concentrations while controlling environmental variables such as temperature and humidity and other variables. This facility enabled experiments designed to investigate collection and desorption efficiencies across a range of sample flow rates, temperature and humidity conditions for both NIOSH sorbent tubes (e.g. SKC tube) and 3M charcoal filter media. As a result of the investigations described in this thesis, the following conclusions are drawn.
Performance of the 3M charcoal filter media for collection and desorption efficiencies for loading, storage time, humidity and breakthrough at low flow rates (<0.5 l/min) were found comparable to the SKC sorbent tube. It is concluded that 3M charcoal media (JK50 and JK40) are suitable for sampling and analyses of hydrocarbons at flow rates <0.5 l/min.
The collection efficiencies of the 3M charcoal filter media were investigated at high flow rates (>0.5l/min) for the same parameters, i.e., loading, temperature and humidity. It is concluded that 3M charcoal filter media can be used with confidence in sampling and analysis of airborne hydrocarbons up to 5 l/min.
The Wheeler-Jonas model was found to satisfactorily predict the adsorption kinetics of the 3M charcoal filter media at different loading values of hydrocarbons. It was therefore concluded that the model can be applied to determine the suitable amount of 3M charcoal filter media prior to sampling for a given loading.
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Alarfaj, Ayman Mohammed Abdullah. "Validation of low resistance filters for gas/vapour sampling." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4257.
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Traditional occupational hygiene assessment of occupational exposures to organic gases and vapours rely on low flow (<200 ml/min) NIOSH sorbent tubes. This work investigates 3M charcoal filter media (JK50 and JK40, 3M, Inc.) for collection and analysis of organic vapours across 0.1-5 l/min. To enable this work, a custom exposure facility was constructed and validated within which organic analyte gas/vapour concentrations could be introduced at known concentrations while controlling environmental variables such as temperature and humidity and other variables. This facility enabled experiments designed to investigate collection and desorption efficiencies across a range of sample flow rates, temperature and humidity conditions for both NIOSH sorbent tubes (e.g. SKC tube) and 3M charcoal filter media. As a result of the investigations described in this thesis, the following conclusions are drawn. Performance of the 3M charcoal filter media for collection and desorption efficiencies for loading, storage time, humidity and breakthrough at low flow rates (<0.5 l/min) were found comparable to the SKC sorbent tube. It is concluded that 3M charcoal media (JK50 and JK40) are suitable for sampling and analyses of hydrocarbons at flow rates <0.5 l/min. The collection efficiencies of the 3M charcoal filter media were investigated at high flow rates (>0.5l/min) for the same parameters, i.e., loading, temperature and humidity. It is concluded that 3M charcoal filter media can be used with confidence in sampling and analysis of airborne hydrocarbons up to 5 l/min. The Wheeler-Jonas model was found to satisfactorily predict the adsorption kinetics of the 3M charcoal filter media at different loading values of hydrocarbons. It was therefore concluded that the model can be applied to determine the suitable amount of 3M charcoal filter media prior to sampling for a given loading.
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Schomburg, Rolf. "Evaluation of methods for detecting endotoxin on filters of heating-, ventilation- and air-conditioning systems." [S.l.] : [s.n.], 2003. http://www.diss.fu-berlin.de/2003/250/index.html.
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Berglund, Joel. "THE PROSPECT OF LIVING FILTERS : Reducing building sector energy demands by improving indoor air quality." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-148548.
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Today people spend all the more time indoors. Asthma, allergies and Sick Building Syndrome (SBS) are affecting an increasing number of people. The remedy for all these affections has long been to increase the volume flow of outdoor air in the ventilation but at the same time cities all over the world are struggling with air pollution and smog rising above endangering levels. Living filters present a new solution where part of the indoor air can be purified and recirculated in a building. This project has compiled research on the area to describe the how and why concerning air purification by plants. Independent research conclude that plants can reduce most hazardous chemical agents in the air. Climate change, global warming and increasing demands on energy performance induces a race for countries and companies to improve energy efficiency in all sectors. To the building engineering sector living filters presents a unique solution to cut ventilation energy loses. A powerful simulation tool IDA ICE was used to estimate the energy saving capacity when a living filter is applied in the lunch room of an office floor. Another simulation software; Comsol Multiphysics was used to illustrate the aspects of ventilation flow when a living filter cabinet is deployed in a room. The simulation results show that for three living filter cabinets each measuring 0,7x0,8x1,73 cm the buildings energy usage is reduced with more than the living filters use to operate. The single room simulations then show how a living filter can be accommodated with both mixing and displacing ventilation. However, these simulations also illustrate the importance of the living filters placement to achieve maximum ventilation efficiency. The conclusions from this work are that living filters can reduce building sector energy demands and provide significant indoor environmental benefits. The main issue for using living filters is identified to be building regulations putting strict demands on outdoor air flow and that the hygienic function of each living filter must be verified before it may replace outdoor air.
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Ghochaghi, Negar. "EXPERIMENTAL DEVELOPMENT OF ADVANCED AIR FILTRATION MEDIA BASED ON ELECTROSPUN POLYMER FIBERS." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3631.
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Electrospinning is a process by which polymer fibers can be produced using an electrostatically driven fluid jet. Electrospun fibers can be produced at the micro- or nano-scale and are, therefore, very promising for air filtration applications. However, because electrospun fibers are electrically charged, it is difficult to control the morphology of filtration media. Fiber size, alignment and uniformity are very important factors that affect filter performance. The focus of this project is to understand the relationship between filter morphology and performance and to develop new methods to create filtration media with optimum morphology.
This study is divided into three focus areas: unimodal and bimodal microscale fibrous media with aligned, orthogonal and random fiber orientations; unimodal and bimodal nanoscale fibers in random orientations; bimodal micrometer and nanometer fiber media with orthogonally aligned orientations. The results indicate that the most efficient filters, which are those with the highest ratio of particle collection efficiency divided by pressure drop, can be obtained through fabricating filters in orthogonal layers of aligned fibers with two different fiber diameters. Moreover, our results show that increasing the number of layers increases the performance of orthogonally layered fibers. Also, controlling fiber spacing in orthogonally layered micrometer fiber media can be an alternative way to study the filtration performance. Finally, such coatings presented throughout this research study can be designed and placed up-stream, down-stream, and/or in between conventional filters.
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Murki, Sai Rohith, and Yaswanth Puttagunta. "CFD Simulation of an Activated Carbon Filter." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13839.
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In various industries, specialized filters with activated carbon are used for adsorbing mercury from air-flows. MRT has eight such Activated CarbonFilters (ACFs) in one of their devices. The main purpose of research is tostudy the flow in the ACF filter and suggest a mathematical model for the complete system through which an improved design can be found.Simulation of a single ACF illustrates how the current system’s air flow does not cover the whole filter leaving part of the carbon bed unused forthe adsorption. This is validated by experimental data. A theoretical studybased on a mathematical model is made and the improved air flow pattern of a re-designed ACF is presented. An additional improvement is that byswitching inlet and outlet the usable time of the filters is prolonged.
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Kumar, Anil. "Estimation and Mapping of Ship Air Wakes using RC Helicopters as a Sensing Platform." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/82910.
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This dissertation explores the applicability of RC helicopters as a tool to map wind conditions. This dissertation presents the construction of a robust instrumentation system capable of wireless in-situ measurement and mapping of ship airwake. The presented instrumentation system utilizes an RC helicopter as a carrier platform and uses the helicopter's dynamics for spatial 3D mapping of wind turbulence. The system was tested with a YP676 naval training craft to map ship airwake generated in controlled heading wind conditions. Novel system modeling techniques were developed to estimate the dynamics of an instrumented RC helicopter, in conjunction with onboard sensing, to estimate spatially varying (local) wind conditions. The primary problem addressed in this dissertation is the reliable estimation and separation of pilot induced dynamics from the system measurements, followed by the use of the dynamics residuals/discrepancies to map the wind conditions.
This dissertation presents two different modelling approaches to quantify ship airwake using helicopter dynamics. The helicopter systems were characterized using both machine learning and analytical aerodynamic modelling approaches. In the machine learning based approaches, neural networks, along with other models, were trained then assessed in their capability to model dynamics from pilot inputs and other measured helicopter states. The dynamics arising from the wind conditions were fused with the positioning estimates of the helicopter to generate ship airwake maps which were compared against CFD generated airwake patterns. In the analytical modelling based approach, the dynamic response of an RC helicopter to a spatially varying parameterized wind field was modeled using a 30-state nonlinear ordinary differential equation-based dynamic system, while capturing essential elements of the helicopter dynamics. The airwake patterns obtained from both types of approach were compared against anemometrically produced wind maps of turbulent wind conditions artificially generated in a controlled indoor environment.
Novel hardware architecture was developed to acquire data critical for the operation and calibration of the proposed system. The mechatronics design of three prototypes of the proposed system were presented and performance evaluated using experimental testing with a modified YP676 naval training vessel in the Chesapeake Bay area. In closing, qualitative analysis of these systems along with potential applications and improvements are discussed to conclude this dissertation.<br>Ph. D.
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Abbass, Omed Akber. "Ozone Interaction with Indoor Building Materials and HVAC Filters." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3771.
Full textAbstract:
As modern life develops, humans spend most of their time inside buildings. Understanding the effects of different building materials that exist indoors on indoor air quality is crucial to ensure comfort, health, and productivity of building occupants. Indoor air quality (IAQ) is an important field of building science that focuses on studying the existence of different compounds indoors. These compounds include: airborne particles such as dust, volatile organic compounds (VOCs) such as carbonyls, reactive gases such as radon, ozone and others. Ozone is a strong oxidant gas that has adverse effects on human health, and is highly reactive with building materials that exist indoors. This reaction may reduce its concentration indoors, but may produce other by-products that could be more harmful for human health than ozone itself.
In this dissertation, ozone reaction with different building materials is investigated in four studies. The first includes studying the effect of indoor carpet fiber type on ozone removal and carbonyl emissions. This study provides valuable data and knowledge about the importance of selecting carpet type and its effect on indoor environment. In the second study, different indoor plants were tested to evaluate their ability to remove ozone. The results from this study show wide variation between plants tested on ozone removal. Also, the ability of plants as ozone removal agent changes as light levels change. The third part studies ozone removal efficiency of HVAC filters previously installed in air handling units located on green and white membrane roofs of a commercial building. Detailed filter surface analysis using scanning electron microscope (SEM) was performed to understand the nature of deposits on these filters. The reason for differences in ozone removal efficiency of two filters in comparison with new filter is also discussed. The fourth study investigated ozone removal and carbonyl emissions from three different VOC content indoor latex paints. The outcomes from this research show that zero VOC latex paint has the most ozone effective removal capacity and this paint is the least carbonyl emitter.
The research presented in this dissertation adds new data, valuable knowledge, and expands the understanding of the importance of selecting indoor materials to raise indoor air quality and make the buildings' indoor environment healthier and safer.
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Szabó, Zoltán. "Příspěvek k optimální syntéze filtračních obvodů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-233563.
Full textAbstract:
The presented dissertation thesis is focused on the optimization of filtering circuit synthesis. In the five main sections of this work, the author analyzes partial problems related to several areas within the synthesis of modern filtering circuits. The first chapter constitutes an examination of elementary aspects which characterize present-day integrated circuits in voltage feedback operational amplifiers, and this main content is further complemented with a view on possible application of these circuits for the designing of filtering circuits as proposed within subsequent parts of the thesis. In this context, the second chapter contains a description of the design and optimization of digitally controlled universal filters tunable by means of digital potentiometers originally produced for audio technology. These digitally controlled circuits are increasingly utilized as analog preprocessing blocks in digital signal processing systems. The most extensive portion of the dissertation is dedicated to a complex analysis of individual configurations of economical, purposely lossy active function blocks and modern voltage operational amplifiers. This part of the thesis aims at providing a detailed insight into the characteristics of individual configurations of examined circuits; furthermore, in this respect, the author proposes a comparison of various application possibilities relating to these circuits and their wider use in the field of active frequency filters optimization. The described section of the work also includes a definition and examples of application of the designed and realized program, which facilitates significant simplification of purposely lossy ARC filters. In the penultimate part of the dissertation thesis, the design, development, and verification of a suitable synthesis procedure are presented together with the optimization of data and (in particular) power models of EMC filters. Based on the verification of characteristics inherent with the designed models of EMC filters, the suggested measuring procedure related to these filters is described, including the design of a station for measuring elementary parameters of line anti-interference devices up to very high frequencies. In the last section of the thesis, the author discusses the procedure of air ions concentration measurement through an aspiration condenser and analyzes the systematic and random errors as well as the optimization of filtration characteristics of the applied measurement method. This part includes the description of the design and characteristics of the realized fully automated measurement system with an aspiration condenser.
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Kuntz, Thomas James. "Campylobacter jejuni and Salmonella spp. Detection in Chicken Grow Out Houses by Environmental Sampling Methods." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/42526.
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Campylobacter and Salmonella are foodborne pathogens commonly associated with raw poultry. Although there has been much research done on isolating these pathogens from poultry production environments using cloacal swabs, fecal samples, intestinal tract contents and dissection, research involving environmental sampling has been limited. New and/or improved environmental sampling methods may provide an easy, convenient, and less time-consuming way to collect samples. Coupling these sampling methods with PCR may provide a relatively simple, rapid, and robust means of testing for foodborne pathogens in a chicken house or flock prior to slaughter.
Air, boot and sponge samples were collected from three commercial chicken grow-out houses located in southwestern Virginia when flocks were three, four, and five weeks old. Air samples were collected onto gelatin filters. Fecal/litter samples were collected from disposable booties worn over investigatorâ s protective shoe coverings. Pre-moistened sponges were used to sample house feed pans and water dispensers on drink lines. A PCR method was used to qualitatively detect Campylobacter jejuni and Salmonella spp. Campylobacter jejuni was detected at each farm (house), across all three ages (3, 4, and 5 weeks), and from each sample type. Salmonella was not detected in any of the environmental samples. For all 270 samples, 41% (110/270) were positive for Campylobacter. Collectively, 28% (25/90) of air, 44% (40/90) of sponge, and 50% (45/90) of bootie samples were positive for Campylobacter. The methods used in this study are non-invasive to live animals, relatively rapid and specific, and could enable poultry processing facilities to coordinate scheduled processing of flocks with lower pathogen incidence, as a way to reduce post-slaughter pathogen transmission.<br>Master of Science
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Jamriska, Milan. "The effect of ventilation and air filtration on reduction of indoor concentration to submicrometer airborne particulates." Thesis, Queensland University of Technology, 2000.
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Ames, Robin W. "Analysis of a 2007 EPA compliant diesel particulate matter sampling system." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5245.
Full textAbstract:
Thesis (M.S.)--West Virginia University, 2007.<br>Title from document title page. Document formatted into pages; contains xv, 133 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 91-95).
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Hamann, Martin Louis. "System hydrodynamics to reduce fouling of air-sparged immersed flat-sheet microfiltration membranes." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5206.
Full textAbstract:
Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2010.<br>ENGLISH ABSTRACT: Immersed membrane systems hold many operational and environmental advantages in biological
treatment of wastewater. However, immersed membrane filtration have only found application in
niche markets to date because of higher capital and operating costs associated with membrane
fouling. But with capital costs on the decline as membranes become less expensive, immersed
membrane systems are increasingly considered as an attractive alternative to conventional
treatment processes. Operating costs remain high however, since energy intensive techniques
such as air-sparging are required to limit membrane fouling. Improving the air-scouring efficiency
of air-sparged immersed membranes can significantly reduce operating costs and unlock the
immersed membrane system technology to wider application.
The aim of this study was to identify factors that will improve air-scouring efficiency in order to
produce guidelines that will help in the development of an immersed microfiltration membrane
system with a resulting lower operating cost. Although, the research was done on a flat-sheet
microfiltration membrane, the guidelines obtained can be used for the development of any
immersed microfiltration membrane arrangement.
An airlift reactor set-up was chosen for this study. Six system hydrodynamic factors were
evaluated in a factorial design to determine their effects on the cross-flow velocity profile. They
were the downcomer area to riser area ratio, top clearance distance, bottom clearance distance,
aeration intensity, water depth and air sparger location. It was found that the air-scouring
efficiency was increased by generating a cross-flow velocity profile with increased magnitude and
uniformity, but absolute uniformity of the cross-flow velocity profile was found to be a prerequisite
for optimisation of air-scouring efficiency. Downcomer area to riser area ratio was found to be
99.9% significant in determining the magnitude of the cross-flow velocity profile.
Two models were developed to respectively predict the relative magnitude and uniformity of the
cross-flow velocity profile. By using these two models, a methodology was developed to design an
airlift reactor set-up that would produce system hydrodynamics with an improved air-scouring
efficiency.<br>AFRIKAANSE OPSOMMING: Gesonke membraanstelsels beskik oor talle bedryfs- en omgewingsvoordele in biologiese
behandeling van afvalwater. Maar weens die hoër kapitaal- en bedryfskostes wat gepaardgaan
met membraanbevuiling, kon gesonke membraanstelsels tot op hede nog net toepassing in
nismarkte vind. Maar soos kapitaalkoste daal met al hoe goedkoper membrane beskikbaar, word
gesonke membraanstelsels al hoe aanlokliker as ‘n alternatief vir konvensionele
behandelingsprosesse. Bedryfskostes bly egter hoog aangesien energie-intensiewe tegnieke soos
lugborreling benodig word om membraanbevuiling te vertraag. Deur die effektiwiteit van die
skropaksie wat lugborreling aan gesonke membrane bied te verbeter, kan ‘n beduidende besparing
in bedryfskostes teweeggebring word om sodoende die uitgebreide toepassing van gesonke
membraanstelsel tegnologie moontlik te maak.
Hierdie studie het ten doel gehad die identifisering van faktore wat lugskropaksie effektiwiteit kan
verbeter en om riglyne op te stel vir die ontwikkeling van ‘n gesonke mikrofiltrasie membraanstelsel
met gevolglik laer bedryfskostes. Alhoewel hierdie navorsing ‘n plat-blad mikrofiltrasie membraan
gebruik het, kan die riglyne steeds vir enige gesonke mikrofiltrasie membraanuitleg gebruik word.
Daar is besluit op ‘n lugligter-reaktor opstelling vir hierdie studie. Ses stelselhidrodinamika faktore
is geëvalueer in ‘n faktoriale ontwerp om hul effekte op die kruisvloei snelheidsprofiel te bepaal.
Hulle was die afvloei-area tot opvloei-area verhouding, topruimte-afstand, bodemruimte-afstand,
belugtingsintensiteit, waterdiepte en belugterligging. Daar is bevind dat die lugskropaksie
effektiwiteit verhoog word wanneer ‘n kruisvloei snelheidsprofiel geskep word met ‘n verhoogde
grootte en gelykvormigheid, maar die absolute gelykvormigheid van die kruisvloei snelheidsprofiel
is gevind om ‘n voorvereiste te wees vir optimale effektiwiteit. Afvloei-area tot opvloei-area
verhouding is gevind om 99.9% beduidend te wees in die bepaling van die snelheidsprofiel se
grootte.
Twee modelle is ontwikkel om afsonderlik die relatiewe grootte en gelykvormigheid van die
kruisvloei snelheidsprofiel te voorspel. Die modelle is in ‘n metodologie vervat vir die ontwerp van
‘n lugligter opstelling met stelselhidrodinamika wat verbeterde lugskropaksie effektiwiteit sal skep.
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Mysen, Mads. "Ventilation systems and their impact on indoor climate and energy use in schools : studies of air filters and ventilation control." Doctoral thesis, Norwegian University of Science and Technology, Department of Energy and Process Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1740.
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Magoha, Paul W. "Incident-response monitoring technologies for aircraft-cabin air quality." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/14187.
Full textAbstract:
Doctor of Philosophy<br>Department of Mechanical Engineering<br>Steven J. Eckels<br>Byron W. Jones<br>Poor air quality in commercial aircraft cabins can be caused by volatile organophosphorus (OP) compounds emitted from the jet engine bleed air system during smoke/fume incidents. Tri-cresyl phosphate (TCP), a common anti-wear additive in turbine engine oils, is an important component in today’s global aircraft operations. However, exposure to TCP increases risks of certain adverse health effects. This research analyzed used aircraft cabin air filters for jet engine oil contaminants and designed a jet engine bleed air simulator (BAS) to replicate smoke/fume incidents caused by pyrolysis of jet engine oil. Field emission scanning electron microscopy (FESEM) with X-ray energy dispersive spectroscopy (EDS) and neutron activation analysis (NAA) were used for elemental analysis of filters, and gas chromatography interfaced with mass spectrometry (GC/MS) was used to analyze used filters to determine TCP isomers. The filter analysis study involved 110 used and 74 incident filters. Clean air filter samples exposed to different bleed air conditions simulating cabin air contamination incidents were also analyzed by FESEM/EDS, NAA, and GC/MS. Experiments were conducted on a BAS at various bleed air conditions typical of an operating jet engine so that the effects of temperature and pressure variations on jet engine oil aerosol formation could be determined. The GC/MS analysis of both used and incident filters characterized tri-m-cresyl phosphate (TmCP) and tri-p-cresyl phosphate (TpCP) by a base peak of an m/z = 368, with corresponding retention times of 21.9 and 23.4 minutes. The hydrocarbons in jet oil were characterized in the filters by a base peak pattern of an m/z = 85, 113. Using retention times and hydrocarbon thermal conductivity peak (TCP) pattern obtained from jet engine oil standards, five out of 110 used filters tested had oil markers. Meanwhile 22 out of 74 incident filters tested positive for oil fingerprints. Probit analysis of jet engine oil aerosols obtained from BAS tests by optical particle counter (OPC) revealed lognormal distributions with the mean (range) of geometric mass mean diameter (GMMD) = 0.41 (0.39, 0.45) [mu]m and geometric standard deviation (GSD), [sigma][subscript]g = 1.92 (1.87, 1.98). FESEM/EDS and NAA techniques found a wide range of elements on filters, and further investigations of used filters are recommended using these techniques. The protocols for air and filter sampling and GC/MS analysis used in this study will increase the options available for detecting jet engine oil on cabin air filters. Such criteria could support policy development for compliance with cabin air quality standards during incidents.
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Дроздова, Ольга Сергіївна, Ольга Сергеевна Дроздова, Olha Serhiivna Drozdova та О. В. Нагорнєв. "Сучасні апарати очищення повітря від забруднювальних речовин зварювального виробництва". Thesis, Сумський державний університет, 2016. http://essuir.sumdu.edu.ua/handle/123456789/45321.
Full textAbstract:
При виконанні зварювальних робіт в повітря виділяється зварювальний аерозоль, у складі якого містяться оксиди металів у вигляді твердих частинок і газоподібні сполуки . Аерозоль, яка утворюється, характеризується дрібною дисперсністю – швидкість витання часток не перевищує 0,1 м/с. Сучасні
апарати, які здатні вловлювати таке забруднення, представлені фільтрами, в основному, лектростатичними та механічними, з ефективністю очищення більше 90%.
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Bosák, Jan. "Teoretické využití nanotechnologie pro filtraci ve vzduchotechnice." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-239959.
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Thesis solves problems using the nanotechnology for air filtration in HVAC systems. Main specialization work is air filtration for clean spaces with high classes of purity. For example Hospitals, sophisticated technology service, pharmacy etc. Thesis is devide for three parts. First part contains foundation infromations about theory and making fabrics by nanotechnology. Next I described laws of physics, That were using during the solving filtration´s issues. Goal for second part was making the experiments, which should show abilities and properties nanofilters during the air filtration in real environment HVAC systems. In the end measure part is compare nanofilters with common filters. There is describe nanofiltres behavior and their possibilies during the filtration as well as. In last part I expressed own opinions on air filtration by nanofibers. Opinions were making throught informations, That I found out in the process working on thesis and my experiences in HVAC field. By this facts I did compare for get a better idea. Additionally last part contains summary infomations from previously parts and own vision to development in the future. Goal work isn´t promotion and advertising sorts technologies. Ask is just summary and describe discovered knowledges, considered opinions ensue from measuring, information from the Net and people Who work in nanotechnology field.
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Гашинська, А. С., та І. В. Коц. "Конструктивне застосування шлюзів у чистих приміщеннях". Thesis, ВНТУ, 2018. http://ir.lib.vntu.edu.ua//handle/123456789/23506.
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У даній доповіді висвітлюється питання створенню чистих приміщень, які забезпечують стерильність
і високоефективного уникнення пилу<br>This report covers the issue of creating clean rooms that provide sterility and highly effective dust avoidance
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Chaves, Karina Oliveira. "Desenvolvimento e aplicaÃÃo de sistema de Floco-FlotaÃÃo por Ar Dissolvido para tratamento de Ãgua de lavagem do filtro da ETA GaviÃo." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8123.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>No cenÃrio brasileiro, os resÃduos de EstaÃÃes de Tratamento de Ãgua (ETAs) sÃo
normalmente lanÃados in natura em corpos hÃdricos, apresentando-se como potencialmente
danosos ao meio ambiente, sendo necessÃrio tratÃ-los para que sejam descartados conforme os
aspectos legais. Estudos demonstram que a tecnologia da FlotaÃÃo por Ar Dissolvido (FAD)
tem sido viÃvel para este fim. Acredita-se que a incorporaÃÃo da floculaÃÃo em cortinas numa
mesma unidade de flotaÃÃo possa promover elevada eficÃcia ao sistema, traduzindo-se como
uma inovaÃÃo tecnolÃgica: o Floco-Flotador por Ar Dissolvido (FFAD). Uma unidade piloto
de FFAD foi construÃda para o tratamento da Ãgua de lavagem dos filtros da ETA GaviÃo,
pertencente à Companhia de Ãgua e Esgoto do Cearà (CAGECE). Esta pesquisa teve como
objetivo quantificar e verificar o atendimento da Ãgua de lavagem dos filtros (ALF) desta
ETA e da Ãgua clarificada via FFAD aos padrÃes de lanÃamento de efluentes conforme as
ResoluÃÃes n 430/11 e 357/05 do CONAMA e Portaria n 154/2002 da SEMACE. Estudos
de tratabilidade da ALF em Jartest foram realizados para avaliar a influÃncia da dosagem de
polÃmeros catiÃnicos e a viabilidade de gradientes de velocidade decrescente (35 a 5,6 s-1) a
serem empregados no equipamento de FFAD desenvolvido. Ensaios de flotaÃÃo foram
realizados a fim de avaliar a dosagem do polÃmero e os parÃmetros de processo como taxas de
recirculaÃÃo (TR) e taxas de aplicaÃÃo superficial (TAS). ApÃs definidos estes parÃmetros,
ensaios de FFAD foram realizados em triplicata para coleta da AC a fim de comparÃ-la com
os principais padrÃes de lanÃamento de efluente em corpos hÃdricos classe II. Somente os
parÃmetros pH, Fluoreto, AmÃnia, E. coli e SÃlidos dissolvidos da ALF atenderam aos
padrÃes de lanÃamento. Ao aplicar polÃmero a 1 mg.L-1, taxa de recirculaÃÃo de 15%,
gradientes de velocidade decrescente (19,3 a 5,6 s-1), taxa de aplicaÃÃo superficial de 57
m3.m-2.d-1 com tempo de detenÃÃo hidrÃulico de 22 minutos no FFAD, os resultados
alcanÃaram elevada eficiÃncia na remoÃÃo de turbidez (superior a 98%) mesmo enfrentando
variaÃÃes bruscas na qualidade da ALF (94,4 a 410 UT). Observou-se tambÃm significativa
eficiÃncia mÃdia na remoÃÃo de coliformes totais (98,5%), cor aparente (97,6%), DQO
(92,6%) e remoÃÃo de alumÃnio (84,1%). Diante destes resultados, constatou-se que a ALF da
ETA GaviÃo tratada via Floco-flotaÃÃo por ar dissolvido atendeu aos referidos padrÃes de
lanÃamento em corpos hÃdricos.<br>In Brazil the filter backwash wastewater is normally released in to the water resources
without proper treatment, representing a potential danger to the environment. Thus, it is
necessary to treat this wastewater in order to dispose it in accordance to federal and state
environmental laws. Studies show that Dissolved Air Flotation (DAF) technology has been
feasible for this purpose. It is believed that the incorporation of flocculation in curtains and
air dissolved flotation system in the same unit can promote high efficiency and significant
size reduction, which translates in a technological innovation: the Floculator - Dissolved
Air Flotation (FFAD) unit. A FFAD pilot unit was built to evaluate the treatment of GaviÃo
Water Treatment Plant filter backwash wastewater, owned by the Water and Wastewater
Company of Cearà (CAGECE). This research had as main objective to quantify and verify
the compliance of the filter backwash wastewater parameters to the Resolution No. 430/11
and 357/05 of CONAMA and Ordinance No. 154/2002 of SEMACE. Treatability studies
were performed with filter backwash wastewater using Jartest to evaluate the influence of
cationic polymer dosages and the feasibility of decreasing flocculation velocity gradients
(35 to 5.6 s-1) in the FFAD. Experimental runs of the flocculation - flotation system were
performed to evaluate the best polymer dosage and the process parameters such as
recirculation rates (TR) and surface application rates (TAS). These parameters were
compared by observing the lower residual turbidity and best removal efficiency in the
clarified water (AC). The treated wastewater was again characterized using physicalchemical
and bacteriological parameters and compared to the specific legislation. The
results showed that the use of 1 mg.L-1 of polymer, recirculation rate of 15% and surface
application rate of 57 m3.m-2.d-1, presented the highest turbidity efficiency removal (>
98%) and a very stable performance against sudden changes in the influent quality (94.4 to
410UT). It should be noted that the unity showed also a high average efficiency total
coliforms removal (98.5%), apparent color removal (97.6%), DOC removal (92.6%), of
aluminum (84.1%) removal and turbidity (99.2 %) removal. Given these results, it was
concluded that the AC coming from the treatment of ALF by ETA WTP GaviÃo FFAD
met the discharge parameters listed for water resources.
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Shirkovskiy, Pavel. "Conjugaison de phase ultrasonore pour la vélocimétrie des écoulements gazeux : investigations des potentialités en micro-fluidique." Phd thesis, Ecole Centrale de Lille, 2010. http://tel.archives-ouvertes.fr/tel-00604511.
Full textAbstract:
La conjugaison de phase ultrasonore à couplage par l'air basée sur une céramique magnétostrictive et une membrane de filtration poreuse pour la microscopie et la vélocimétrie de micro écoulements a été développée. Dans ce but, dans le cadre de l'acoustique géométrique un système d'équations pour décrire mathématiquement le passage par l'interface entre l'élément actif du système de conjugaison de phase confocale - milieu de propagation a été développé.On a développé et réalisé une technique de codage de phase par m-séquence pour l'enregistrement des faibles signaux conjugués en phase. Cette technique a permis de travailler plus efficacement avec fort bruit et des signaux qui se trouvent sous le niveau de bruit. Aussi cette technique a permis d'améliorer une méthode de vélocimétrie des écoulements gazeux.On a développé et réalisé une technique d'adaptation d'impédance acoustique basée sur la membrane de filtration poreuse imprégnée par de l'huile. Cette technique a permis d'optimiser les conditions de transmission de l'onde à l'interface air-ferrite aux fréquences basse dans bande du MHz.Les applications possibles de l'effet de conjugaison de phase paramétrique à la vélocimétrie des écoulements gazeux et à la microscopie à couplage par l'air ont été présentées. L'application de l'effet de conjugaison de phase permet d'améliorer les performances des méthodes de vélocimétrie et de microscopie ultrasonores à couplage par l'air. Les méthodes élaborées a repoussé les limites d'applications pratiques de l'effet de conjugaison de phase et peuvent être utilisées pour le développement des dispositifs en vélocimétrie, microscopie et tomographie ultrasonore des écoulements gazeux
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Raghavan, Bharath Kumar. "Nanofiber Filter Media for Air Filtration." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1279744866.
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Spinelle, Laurent. "Microsystèmes capteurs de gaz sélectifs au dioxyde d'azote associant structures semi-conducteurs et filtres chimiques (indigo ou/et nanomatériaux carbonés) destinés au contrôle de la qualité de l'air." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00741969.
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Ce manuscrit est consacré à l'étude et au développement de microsystèmes capteurs de gaz sélectifs au dioxyde d'azote, destinés au contrôle de la qualité de l'air atmosphérique. La stratégie que nous avons développée consiste à associer une structure sensible à base de matériaux semi-conducteurs partiellement sélectifs aux gaz oxydants et des filtres sélectifs à l'ozone. L'objectif premier est la mise en oeuvre et la caractérisation de matériaux chimiques strictement imperméables à l'ozone (O3) et non-réactifs vis-à-vis du dioxyde d'azote (NO2). Notre choix s'est focalisé sur un matériau moléculaire, l'indigo, connu pour sa réactivité vis-à-vis de O3, et plusieurs nanomatériaux carbonés. Pour ces derniers, la possibilité de conformer leurs textures, leurs morphologies et leurs chimies de surface par traitements thermiques, chimiques et mécaniques, permet d'étendre le panel de matériaux potentiels et d'identifier les facteurs d'influence de leur réactivité avec les espèces gazeuses. La caractérisation de l'ensemble de ces matériaux a nécessité l'utilisation de techniques adaptées et complémentaires (adsorption de N2 à 77 K, spectroscopies Raman, XPS, IR en mode ATR, RPE et NEXAFS). Les filtres chimiques les plus efficaces (hauts rendements de filtration et grande durabilité) ont été sélectionnés d'après des tests de soumission aux gaz selon une méthodologie adaptée. Enfin, l'association de ces meilleurs filtres et de la structure capteur a conduit à l'élaboration de prototypes microsystèmes capteurs de gaz optimisés. De plus, une contribution à la compréhension des mécanismes d'interaction de l'indigo et de certains nanocarbones avec O3 et NO2 a aussi permis d'améliorer le microsystème en développant des méthodologies pertinentes et innovantes mais également en réalisant la synthèse de nouveaux filtres indigo / nanocarbone.
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Dhordain, Hélène. "Fonctionnalisation d’une structure nontissée par la cyclodextrine pour l’élaboration d’un filtre textile biocide." Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10194/document.
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La menace d’une pandémie mondiale (du type H1N1) amène nos sociétés à se protéger des microorganismes infectieux. Différentes solutions permettent de se protéger de ces microorganismes. En dehors de la vaccination et autres prophylaxies, il existe des moyens de protection individuelle ou collective qui consistent à filtrer l’air respiré pour en extraire les aérosols infectieux. L’objet de cette thèse a consisté à élaborer une structure textile filtrante pourvue de propriétés biocides. Dans un premier temps, le textile a été fonctionnalisé par la cyclodextrine, molécule cage connue pour ses propriétés complexantes vis-à-vis de molécules variées. Les paramètres de l’ennoblissement du textile par la cyclodextrine ont été optimisés afin de ne pas dégrader le support. Des tests biologiques ont mis en évidence une bonne cytocompatibilité du textile modifié. Les textiles ont ensuite été activés par imprégnation par des agents biocides. Des essais de cinétiques de libération ont montré que les biocides étaient solidement fixés sur le support. Des tests de microbiologie ont révélé leur bonne biodisponibilité par le biais d’une réduction remarquable de l’adhésion bactérienne. Enfin, l’étude a été complétée par des tests de filtration d’aérosols standards, qui ont montré que la modification des fibres ne perturbait pas les propriétés filtrantes du textile. Ainsi nous avons réussi conférer des propriétés anti-infectieuses à une structure textile sans détériorer ses performances de filtration<br>The threat of a worldwide pandemic (like H1N1) leads occidental societies to develop protections against infectious microorganisms. Defenses against microorganisms can be organized around some solutions. Apart from vaccination or other prophylaxis, individual or collective protections consist in the filtration of the air in order to remove infectious particles. The aim of this thesis consisted of working out a textile structure capable of biocidal properties. First, textile has been functionalized by cyclodextrin. Cyclodextrins are host molecules which have the capability to make inclusions (or host–guest) complexes with a wide range of molecules. Parameters of the curing were improved in order to minimize the textile structure spoiling. Biological tests have proved the good cytocompatibility of the modified textile. Then textiles have been activated with biocidal molecules. Kinetics of release have shown that biocides were durably fixed on the textile and microbiological tests have demonstrated their bioavailability through a striking reduction of the bacterial adhesion. Finally, this study was completed by mechanical and filtration tests which have revealed that fibers modification did not disturb filtration properties of textile. Finally, we succeeded in offering biocidal properties to a textile structure without affecting its filtration performances
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Forthomme, Audrey. "Caractérisation du comportement des aérosols microbiens dans les réseaux de ventilation d'espaces occupés." Phd thesis, Ecole des Mines de Nantes, 2012. http://tel.archives-ouvertes.fr/tel-00782957.
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La qualité microbienne de l'air intérieur représente un enjeu sanitaire important, notamment dans le secteur professionnel. Ces travaux de thèse ont permis d'étudier les conditions favorisant le développement des espèces microbiennes collectées sur des médias fibreux utilisés dans des CTA, ainsi que leur réentrainement an aval de la filtration, susceptible de dégrader la qualité de l'air. La première partie de l'étude s'est déroulée en laboratoire à partir de la filtration d'un consortium bactérien - fongique composé de Staphylococcus epidermidis et Penicillium oxalicum. L'influence de trois paramètres a été étudiée sur la croissance microbienne : le taux d'humidité relative (HR) de l'air, la nature du média fibreux, la présence/absence de flux d'air. Les résultats ont révélé notamment que quelles que soient les conditions,S. epidermidis n'arrive pas à croître. En revanche, lorsque l'HR de l'air approche 100%, P. oxalicum se développe sur les filtres et des spores sont relarguées en aval des filtres après une reprise de la filtration. Une seconde partie de l'étude a consisté à travailler avec un aérosol atmosphérique semi urbain. Deux unités de filtration d'air ont fonctionné pendant 5 mois en parallèle. La ventilation d'une des deux unités a été stoppée chaque week-end et redémarrée en début de semaine. Un suivi de la température, de l'humidité de l'air, de la perte de charge des filtres et de la concentration des particules totales dans l'air en amont de la filtration a été assuré tout au long de l'étude. Les concentrations en microorganismes cultivables ont été mesurées chaque semaine en amont et en aval de chaque filtre, notamment au redémarrage de la ventilation. En fonction des variations saisonnières de la concentration des microorganismes, les résultats ont montré en particulier des efficacités de filtration vis-à-vis des particules bactériennes faibles, voire négatives, dans l'unité de filtration fonctionnant en continu.
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Bourrous, Soleiman. "Étude du colmatage des filtres THE plans et à petits plis par des agrégats de nanoparticules simulant un aérosol de combustion." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0301/document.
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Dans les installations nucléaires, les particules en suspension sont le vecteur d’une grande partie de la contamination radiologique. Pour cette raison, l'IRSN (Institut de Radioprotection et de Sûreté Nucléaire) étudie les filtres THE (Très Haute Efficacité) plissés qui sont l'un des dispositifs permettant assurer la sécurité de l'exploitation nucléaire. Pour éviter les rejets dans l'environnement, la compréhension du comportement des filtres en particulier dans la situation accidentelle doit être aussi exhaustive que possible. L'accident le plus probable et le plus pénalisant pour les dispositifs de confinement est l’incendie qui conduit à une production massive de particules de suie. Dans ce cas, le colmatage des filtres est un problème qui doit être pris en compte. Jusqu'à présent, une corrélation empirique a été développée pour prédire l'augmentation de perte de charge. Toutefois, le caractère empirique de cette corrélation ne permet pas son utilisation dans toutes les situations. Une compréhension phénoménologique et un modèle de colmatage est alors nécessaire. Le travail de thèse qui suit vise à lier l'évolution de la perte de charge à des observations physiques pour chaque étape du colmatage. Pour ce faire, l'étude a été divisée en deux parties. La première se focalise sur le comportement du filtre plan en mesurant la pénétration de particules à l'intérieur du medium et la porosité du dépôt formé sur sa surface. La deuxième partie consiste en une expérience à petite échelle basée sur un seul pli. L'accumulation de particules à l'intérieur du pli a été directement observée, de plus, la déformation du pli ainsi que les écoulements d'air dans le pli (en utilisant une méthode de PIV) ont été mesurés. Au cours de ces expériences, la perte de charge a été mesurée et les paramètres mesurés ont été liés à l'évolution de la perte de charge. La finalité est de construire un modèle analytique simple afin de prédire l'évolution de la perte de charge des filtres en fonction de la masse déposée, des caractéristiques de l'aérosol et des conditions aérauliques. La principale perspective ouverte par ces résultats est la validation des modèles numériques complets pour surmonter les limites expérimentales. Le prolongement logique de ce travail sera l'étude du comportement d'un filtre colmaté soumis à des contraintes de température, d’humidité et aux agressions chimiques de produits de combustion<br>In nuclear facilities, airborne particles are the vector of most of the radiological contamination. For this reason, pleated HEPA filters are one of the containment devices which are actively studied by the IRSN (Institut de Radioprotection et de Sûreté Nucléaire) to ensure the safety of nuclear exploitation. To avoid contamination of the environment, the understanding of the behavior of the filters especially in accidental situation has to be as exhaustive as possible. The most probable accident and the most penalizing for the containment devices is fire which leads to a massive soot particle production. In this case, the clogging of the filters is a problematic which has to be taken into account. Up to now, an empirical correlation has been developed to predict the pressure drop increase. The empirical nature of this correlation doesn’t allow its use in all situations. A phenomenological understanding and model of the clogging is then necessary. The following PhD work aims to reduce the pressure drop evolution to physical observations for each step of the clogging in order to model it on the most physical basis as possible. To do so, the study has been divided in two parts. The first one focusing on the behavior of flat filter by measuring the penetration of particles inside the medium and the porosity of the deposit formed on its surface. In the second part a small scale experiment based on a single pleat has been developed. Accumulation of the particles inside the pleat has been directly observed, deformation of the pleat as well as airflow in the pleat (using a PIV method) has been measured. During these experiments, pressure drop has been monitored and the measured parameters have been linked to the pressure drop evolution. Finality is to build a simple analytical model to predict the pressure drop evolution of the filters as a function of the deposited mass, the aerosol characteristics and the ventilation conditions. The main perspective opened by these results is the validation of complete numerical models to overcome the experimental limits. The logical extension of this work will be the study of the interaction of a clogged filter with temperature, air moisture and chemical aggression
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Matula, Tomáš. "Techniky umělé inteligence pro filtraci nevyžádané pošty." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2014. http://www.nusl.cz/ntk/nusl-236060.
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This thesis focuses on the e-mail classification and describes the basic ways of spam filtering. The Bayesian spam classifiers and artificial immune systems are analyzed and applied in this thesis. Furthermore, existing applications and evaluation metrics are described. The aim of this thesis is to design and implement an algorithm for spam filtering. Ultimately, the results are compared with selected known methods.
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Niu, Hejingying, and 牛何晶英. "Nitric oxide removal by wastewater bacteria in a biotrickling filter." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50533885.
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Nitric oxide (NO) is one of the most important air pollutants in atmosphere mainly emitted from combustion exhaust gas. In this research, a biotrickling filter was designed and operated to remove this pollutant from an air stream using bacteria extracted from the sewage sludge of a municipal sewage-treatment plant. The bacteria were cultured and enriched by either petri dish’s cultivation or liquid cultivation. The adsorption capacity of the ceramic material, which was used as the packing material, was determined to be 34 g-NO/L under 37℃. However, the saturated adsorption capacity of the packing material with the recycling solution is 236 mg-NO/L under the operation temperature 37℃.The result suggested that the microporous structure of the ceramic material not the humidity is the main contributor to the ceramic material adsorption capacity. Both the ceramic material adsorption capacity and the removal capacity of the liquid were limited and saturated in 540 min and 2 min operation, respectively. To obtain the best operation conditions for the biotrickling filter, orthogonal experiments (L9 (34)) were designed. The experimental data were analyzed by the signal to noise (S/N) ratio and ANOVA. The optimal conditions of the biotrickling filter occurred at a temperature of 40℃, a pH of 8.00.05 and a chemical oxygen demand (COD) of 165 mg/L in the recycled water with no oxygen in the system. Inlet oxygen concentration was found to be the most significant factor of the biotrickling filter that has a significant negative effect on the NO removal efficiency.
The DNA sequencing of four clones of bacteria showed 93-98% similarity to Pseudomonas mendocina strain. This strain has been analysed by full gene sequencing and proved to be a brand-new strain named as Pseudomonas mendocina DLHK. This strain can transfer nitrate to organic nitrogen. This result indicated the assimilation nitrogen process in this system and suggested that the main nitrogen removal capacity in this system was through biological function.
Through the isotope experimental analysis, two intermediate products (15NO and 15N2O) have been found during the biological process of the system by using quantitative gas analysis (QGA). These results indicated the denitrification function in this biotrickling filter. A model was developed to explain the biological process in the biotrickling filter. The averaged error of the measured and modeled data is -0.047. The standard deviation of the error is 0.039. The model prediction is in good agreement with the experimental data, particularly at small packing height. Most NO removal capacity was achieved at the first 5 cm packing material. The effects of the axial interstitial velocity and the biofilm coverage to the NO elimination were studied by the model that provided a basic for the design of a biotrickling filter.
The biotrickling filter could be used for exhaust gases treatment. The assimilation function in the biological system could be another way to utilize the nitrogen component in the waste gas from harmful to benign nature. The isotope labeling technology is a new method to detect gas components for complex gas samples.<br>published_or_final_version<br>Mechanical Engineering<br>Doctoral<br>Doctor of Philosophy
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Venturini, Giacomo. "Design of experiment analysis of air filter performance for helicopter applications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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Helicopters are used in different situations and in extremely various environments. Sometimes they land or take off to or from rough landing sites where dust, sand and other materials are present. One of the major problem for helicopters engine is the ingestion of these materials. This problem can be solved by using a filter positioned at the engine intake.
The filtration in helicopters is a recent development because, until recent times, research in this field was considered non-profitable and downplayed. Filtration is closely connected with engine efficiency and, in recent years, it has been seen that with a small investiment, helicopter performances were much better. A good filtration means less consumption and more perfomance.
This work is a part of a project conducted by BMC Air Filters, a company known worldwide for the production of high performance air filters and air induction systems. The goal of the main project consists in studying the optimization of the process in the design of filter elements for helicopters.
The two important features to evaluate an Inlet Barrier Filter are the pressure drop and the capture efficiency. In this work the first aspect is treated.
In the engineering design process, the experimentation plays an important role. In this thesis the Design Of Experiment (DOE) method is used to minimize the number of tests conducted, reaching several positive results. Indeed, in order to decrease the pressure loss, the two parameters to change are materials and geometric shape. Thus, two different materials of filter and several different filter geometric shapes are investigated through DOE, leading to identify the best design solution.
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Malmborg, Petter. "Engine air filter requirements : How different running conditions affect service life." Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-74614.
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The internal combustion engine requires clean air in order to operate without problems the entire service life. The air filter acts as a barrier between the ambient air ridden with particulate matter, and the sensitive interior of the engine. Several factors affect the air filter performance, such as pressure drop, efficiency, and dust holding capacity. Many external factors affect the air filter too, such as driving style, engine type, if the car is equipped with hybrid propulsion et cetera. The scope for this thesis work aims to extend the knowledge of air filtration for the customer, in this case, Volvo Cars. A comprehensive literature study along with benchmarking of competitors acts as a foundational approach. Regarding air filter service life, three parameters are identified as the most significant: dust holding capacity, efficiency and pressure drop over the filter element. Reverse engineering shows some competitor design decisions. A model of estimating air consumption is developed using a data-driven approach with real-world driving data as a basis. The model shows how much the actual air consumption varies between different markets and various engines. As a result, the service lifetime of air filters in certain cars with certain engines may be extended or allow for a smaller filter size for the same service lifetime.
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Zoogman, Peter William. "Geostationary satellite observations of ozone air quality." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11109.
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Ozone in surface air is the primary cause of polluted air in the United States. The current ozone observing network is insufficient either to assess air quality or to fully inform our understanding of the factors controlling tropospheric ozone. This thesis investigates the benefit of an instrument in geostationary orbit for observing near surface ozone using Observing System Simulation Experiments (OSSEs).<br>Earth and Planetary Sciences
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Mehdizadeh, Seyedeh Neda. "Drop Motion and Modeling of the Saturation within Depth Coalescing Filter." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1607007315571927.
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Bandaly, Victor. "Etude de la persistance de virus sur les filtres des centrales de traitement d'air : influence des paramètres de procédé et impact sur la santé." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B038/document.
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La pollution de l'air est l'un des principaux problèmes de santé publique de notre siècle et surtout de l'air intérieur alors que nous passons environ 90% de notre temps dans des environnements fermés. Parmi les polluants les bioaérosols ont été peu étudiés. Cependant des études épidémiologiques ont déjà montré une relation entre les bioaérosols et la santé. Le but de cette thèse est d’étudier les virus respiratoires dans les milieux clos via les systèmes de ventilation. A l’issue d’un état de l’art des polluants de l’air, il est important de définir ceux nécessitant d’être traités, les systèmes de ventilation, les procédés de filtration par médias fibreux et les procédés de traitement pouvant être mis en oeuvre. Les effets des bioaérosols viraux dans les environnements intérieurs sur la santé publique ont été discutés dans une revue bibliographique. Une méthodologie a été mise en oeuvre pour étudier le comportement des virus dans une centrale de traitement de l’air (CTA). Les virus respiratoires, mengovirus (virus nu à ARN de la même famille que les rhinovirus responsables du rhume) et adénovirus (virus respiratoire nu à ADN), ont été choisis et étudiés dans un système expérimental miniature représentatif des systèmes de traitement d’air. La performance de filtration d’un filtre de CTA vis-à-vis des aérosols viraux a été évaluée avec une validation du système expérimental utilisé. Cette étude a montré la capacité des virus de passer à travers le filtre tout en restant infectieux. Peu de littérature existant sur le sujet, ce projet a permis d’ajouter de nouvelles données pertinentes quant à la persistance des virus respiratoires dans l’air intérieur et plus précisément au niveau des filtres dans les centrales de traitement d’air<br>Air pollution is one of the major public health problems of our century and especially of indoor air as we spend about 90% of our time in closed environments. Among pollutants bioaerosols have been poorly studied. However, epidemiological studies have already shown a relationship between bioaerosols and human health. The aim of this PhD work is to learn about respiratory viruses in closed environments via ventilation systems in order to study indoor air quality. At the end of state of the art of air pollutants, it is important to define those present in the air that need to be treated, ventilation systems, filtration processes by fibrous media and the processing methods being able to be implemented. The effects of viral bioaerosols on public health in indoor environments were discussed and drafted in a bibliographic review. The methodology of the study was to assess the fate of respiratory viruses, mengoviruses and adenoviruses, in a miniature experimental system similar to air treatment systems used in closed environments. The experimental system used was validated and the filter performance against viral aerosols was investigated. This study presented originality for the characterization and the fate of two non-enveloped respiratory viruses, mengovirus (RNA) and adenovirus (DNA), in indoor environments and their fate on fiber glass filter. This study showed the ability of viruses to pass through the filter and to remain infectious upstream and downstream the filter. There is scarce literature on this subject, and this project allowed us to add new relevant data on the persistence of respiratory viruses in indoor air and more precisely at the level of filters in air handling units