Dissertations / Theses on the topic 'Forced air purification system'

Striving to improve performance and lower weight of aircraft engines, modern compressor blades become thinner and lighter but higher loaded resulting in an increased vulnerability towards flutter. This trend is further aggravated through blisk designs that diminish structural damping and therewith flutter margin. Modern 3D wide-chord blade designs result in complex structural behaviors that add to the difficulty of correctly predicting flutter occurrence. To counteract above tendencies by driving the physical understanding of flutter and thereby helping to improve aero engine design tools, free flutter as well as forced response will be investigated in the 1.5 stage transonic compressor at TU Darmstadt. Aim of the forced response campaign is to determine the system damping in the stable compressor regime. Hence a novel excitation system capable of dynamically exciting specific rotor blade modes is needed. It is aim of the present work to find a promising concept for such a system. In the present work, the requirements for an excitation system to be used in the TUD compressor are defined with respect to achievable frequency, phase controllability, transferred excitation level, mechanical robustness, integrability and cleanliness. Different excitation system concepts, i.e. oscillating VIGVs, rotating airfoils, tangential and axial air injection are investigated numerically. An evaluation of the results obtained through 2D numerical studies proposes axial air injection as the most favorable concept.
Master of Science

Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2016.
Poultry slaughterhouse wastewater (PSW) contains organic matter that can be degraded by microorganisms. Such matter can further be used by the microbial community as a nutrient source for growth. Moreover, this type of wastewater also contains a high quantity of particulate matter, lipids and proteins, including antimicrobial compounds such as triclosan (TCS) and trichlorocarbanilide (TCC) used during cleaning and sanitising of processing facilities. Lipids and particulate matter lead to clogging of pipes and fouling of diffusers in the wastewater treatment plants (WWTPs). To overcome this problem, a pre-treatment system such as a dissolved air flotation system (DAFs) in which synthetic flocculants are used, is commonly used prior to the biological treatment of the wastewater. Synthetic flocculants add to the environmental burden associated with the use of synthetic compounds, particularly when these compounds are used in WWTPs. This study focused on the reduction of suspended solids, lipids and proteinaceous matter using a bioflocculant- supported DAF for the treatment of PSW.

This study compared the sludge characteristics of a lab-scale Air Products (A/O) and a conventional activated sludge system. The sludges were analyzed for operational properties and the exocellular biopolymers of each sludge was characterized. Operational analysis mainly consisted of measurements of settling (SVI) and dewatering (specific resistance, CST) parameters at each sludge age. Biopolymers were measured using pH extraction followed by gel filtration and subsequent analysis for carbohydrate and protein concentrations. The results showed a high degree of similarity between the two systems both operationally and with respect to biopolymer characteristics. The A/0 system did produce a lower effluent soluble COD at sludge ages below 5 days. Also, the A/O system showed some consistent differences in the distribution of bound and unbound fractions of protein and carbohydrate ECP but these had no discernible· effect on sludge operational characteristics. In addition relationships between unbound ECP and effluent BOD, bound HMW ECP and SVI, and phosphorus and Mg uptake were observed, with varying degrees of consistency, in this study.
Master of Science

Water stress is an ongoing problem in many places in the world, while the demand for clean and safe freshwater is growing due to the increasing population. In many developing countries, water supplies often are contaminated with arsenic, fluoride, etc. Therefore, it is important to realize that water scarcity and contamination issues concern only one sector but many. HVR Water Purification AB is developing a water purification prototype – ELIXIR 500 - using the air gap membrane technology and is implemented in Odisha, India, aiming to supply with 200 litre water daily. This thesis aims to estimate future energy sources to supply this prototype and explore the possibilities of using only renewable energy resources from technical, economic, and environmental perspectives. These are achieved by firstly identifying the energy possibilities in Odisha, India, and then calculating the feasibility of each solution chosen and finally analyzing the results. Among the energy sources, which are power grid, wind and solar power, diesel generator and solar-diesel hybrid system. It is found that the energy source to the prototype supplied by the power grid is 0.057 USD per litre water, which is the cheapest option. However, it is not feasible due to the lack of electrification from the local network. Meanwhile, the solar-diesel hybridized energy system is the most economical option if renewable energy sources are integrated with 0.11 USD per litre water.
Vattenstress ett pågående problem på många ställen i världen medan efterfrågan på rent och säkert dricksvatten växer på grund av den ökande befolkningen. I många utvecklingsländer är vattenförsörjningen ofta förorenade med arsenik, fluor osv. Det är därför viktigt att inse att vattenbrist och föroreningar inte bara rör en sektor utan många. HVR Water Purification AB utvecklade en prototyp för vattenrening - ELIXIR 500 - med hjälp av luftspaltmembrantekniken (eng: air gap membrane distillation och implementeras redan i Odisha, Indien, med målet att förse 200 liter rent vatten dagligt. Denna avhandling syftar till att uppskatta de framtida energikällorna för att tillhandahålla denna prototyp och utforska möjligheterna att endast använda förnybara energikällor ur tekniska, ekonomiska och miljömässiga perspektiv. Dessa uppnås genom att först identifiera de olika energimöjligheter i Odisha, Indien, följt av beräkningar om utförbarhet för varje vald lösning och slutligen en analys av resultaten. Bland energikällorna elnät, vind, sol, diesel generator och sol-diesel hybrid system har visat sig att energikällan till prototypen som levereras av elnätet som kostar 0.057 USD per liter vatten som det billigaste alternativet, men det är inte möjligt på grund av bristen på elektrifiering från det lokala elnätet. Å andra sidan är det hybridiserade energiskombinationen med solkrafts och diesel det billigaste alternativet om förnybara energikällor ska integreras, resultatet visade att vara 0.11 USD per liter vatten.

Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017.
In the recent past, the poultry industry in South Africa has grown due to an increased demand of poultry products as a result of population growth and improved living standards. Furthermore, this has led to poultry slaughterhouses generating high strength wastewater which is laden with a high concentration of organic and inorganic pollutants from the slaughtering process and sanitation of equipment and facilities. As a result, South Africa has promulgated restrictions and a set of quality standards for effluent discharged into the environment to minimize ecological degradation and human health impact. Hence, there is a need for improved Poultry Slaughterhouse Wastewater (PSW) pre-treatment prior to either discharge into municipal wastewater treatment plants (WWTP) or on-site secondary treatment processes such as anaerobic digesters. Additionally, amongst the pre-treatment methods for Fats, Oil and Grease (FOG) laden wastewater, flotation remains the most popular with Dissolved Air Flotation (DAF) system being the most applied. However, modelling and optimization of a biological DAF system has never been attempted before in particular for a bioflocculant supported DAF (BioDAF) for PSW pre-treatment. Process modelling and optimization involves process adjustment to optimize influential parameters. In this study, Response Surface Methodology (RSM) was used to develop an empirical model of a BioDAF for pre-treatment of PSW, for which a bioflocculant producer including production conditions, flocculant type and its floc formation mechanism, were identified. Twenty-one (n = 21) microbial strains were isolated from the PSW and their flocculation activity using kaolin clay suspension (4g/L) was quantified, with a mutated Escherichia coli (mE.coli) [accession number LT906474.1], having the highest flocculation activity even in limited nutrient conditions; hence, it was used for further analysis in other experiments. Furthermore, the optimum conditions for bioflocculant production achieved using RSM were pH of 6.5 and 36°C conditions which induced instantaneous bioflocculant production with the highest flocculation activity. The bioflocculant produced by the mE.coli showed the presence of carboxyl/amine, alkyne and hydroxyl functional groups, which was indicative that the bioflocculant contained both polysaccharides and some amino acids.

L'évaluation expérimentale des échanges convectifs avec l'air est faite sur des ailettes circulaires d'un arbre en rotation à vitesse uniforme et soumises ou non à un courant d'air parallèle à leurs faces. Un banc d'essais a été conçu pour mesurer, par thermographie infrarouge, l'évolution temporelle des températures suivant un rayon d'une ailette durant son refroidissement, cette dernière ayant été préalablement chauffée. Une analyse théorique des phénomènes thermiques se produisant dans une ailette, en régime transitoire, permet de déterminer le coefficient d'échange moyen de celle-ci avec l'air. L’étude bibliographique de la structure d'écoulement entre les ailettes en fonction de leur espacement, de leur vitesse de rotation et de la vitesse du courant d'air a été réalisée. Cette étude sert de base à l'analyse physique de la variation du coefficient d'échange en fonction des différents paramètres. Les essais avec les ailettes en rotation, soumises ou non à un courant d'air parallèle, ont permis de mettre en évidence les domaines d'influence de la convection forcée due à la rotation, de la convection forcée due au courant d'air et de la convection naturelle. Les résultats obtenus sur le coefficient d'échange en convection forcée sont justifiés par la représentation du champ des vitesses de l'écoulement entre les ailettes par vélocimétrie par images de particules. L’ensemble des essais réalisés peuvent être corrélés avec un écart relatif inférieur à 5% par une équation générale.

This dissertation is divided into three parts. The first part deals with the use of waste heat in the theoretical plane, where methods and possibilities of using this heat are described. Part Two, which is computational, deals with the suggestion of heating industrial halls with an adjacent, mostly office, building in two variants, then it goes on to also deal with the concept of equal pressure forced ventilation, a proposal of air curtains and preparation of hot water, where the heat source is a boiler. In the last part an experiment took place which investigated the conversion efficiency of thermal to electric energy.

This master´s thesis addresses heating of the new three - storey office building, which is located in Brno Pisárky. The heating system is designed as a low-temperature system with forced circulation of water using mostly panel radiators. As the heat source was designed two variants. The first heat source is the heat pump air - water, which is installationed inside. The second heat source is a gas condensing boiler. The part of design is preparation hot water. Ventilation of the building is equal-forced. Experimental part of master´s thesis is focused on measuring the amount of electricity produced per year by photovoltaic panels on the existing house in Brno Pisárky. Thesis also includes measuring outdoor temperature and intensity of solar radiation. The result is a comparison of the need for electricity for the heat pump for heating family house, total electricity consumption family house and amount of electricity produced by photovoltaic panels.

The main concern of this thesis is to design heating system for 5 storey apartment building in two alternatives of heat source - with a heat pump and with traditional gas boiler. Both applications are connected to two-pipes distribution system in building using the low-temperature water and radiators. The proposal takes account of the the production of hot water. The one of aims is to compare both variants also from the economic point of view. The experimental part is divided into two parts. The first part deals with the obligation to control efficiency of boilers, imposed by the Energy efficiency law No. 177/2006 Co. and § 6, sect. 2 - 5 and related regulation No. 276/2007 Co. The second part deals with the assessment of monitored room for proper regulation of the heating system.

This work is devoted to the design of a microclimate facility in a family house. The first part contains analysis of thermal losses before and after using thermal insulation. Based on this analysis, a heating system is proposed, including the necessary technical calculations for the operation of the system. As a heat source, a condensing boiler is selected. At the next point, the thesis focuses on the calculation of the heat gains in selected rooms in order to design a cooling device. A multisplit system is selected for cooling the rooms. In the next part the thesis deals with the design of forced ventilation of selected rooms. The ventilation system provides the necessary air exchange and covers heat losses through ventilation. At the end of the thesis is outlined the concept of regulation of individual systems and also the requirements for individual professions are described.

La gestion thermique des batteries Li-ion pour le véhicule électrique est essentielle, pour assurer une autonomie et une durée de vie optimales de ces batteries. Habituellement, des circuits d'air ou de liquide de refroidissement sont utilisés comme systèmes de gestion thermique. Cependant, ces systèmes sont coûteux en termes d'investissement et d'exploitation et doivent être dimensionnés sur la puissance maximale à extraire. L'utilisation de matériaux à changement de phase (MCP) pour l’absorption sous forme de chaleur latente de la chaleur à dissiper peut représenter une alternative moins coûteuse et plus facile à utiliser. En effet, les MCP peuvent stocker passivement la chaleur excédentaire produite et être utilisés en tant que systèmes passifs. Cependant, les MCP présentent de nombreux inconvénients comme la difficulté de décharger l’énergie thermique stockée, ce qui limite l’aptitude du système au cyclage, ou encore leur conductivité thermique peu élevée qui limite les capacités d’échange. Pour résoudre le problème de la régénération des MCP, un système actif supplémentaire peut être ajouté, dimensionné sur une puissance modérée; l'ensemble devient alors un système semi-passif. Dans cette étude, un système de gestion thermique composé d'un MCP et d’air en convection forcée est évalué. Ce système permet de coupler les avantages de ces deux techniques. Une modélisation du système est développée pour une cellule de batterie. Une comparaison avec de l’air uniquement, en convection forcée, montre l'utilité du MCP. Pour augmenter la capacité d’échange du MCP, un matériau à haute conductivité thermique peut être ajouté au MCP, ce qui permet d’obtenir un composite ayant une conductivité thermique plus élevée. Des composites basés sur les MCP étudiés et des nanostructures de carbone sont élaborés, leur conductivité thermique est mesurée. Ensuite, un système expérimental simulant la dissipation d’une cellule de batterie est construit et utilisé pour évaluer le MCP seul, le MCP inclus dans une mousse métallique et le meilleur composite obtenu. Enfin, pour se rapprocher des conditions réelles, un modèle représentant un stack entier de batterie est développé, des simulations sont produites et les résultats obtenus sont commentés
Li-ion battery thermal management is essential for electric vehicles (EVs), to ensure an optimal autonomy and lifespan of those batteries. Usually, air or coolant circuits are employed as thermal management systems. However, those systems are expensive in terms of investment and operating costs and must be dimensioned on the maximal power to be extracted. The use of phase change materials (PCMs) as latent heat storage medium allowing the absorption of the heat to be dissipated as latent heat may represent an alternative cheaper and easier to operate. In fact, PCMs can passively store the excess heat produced by a device and be used as passive systems. However, PCMs have several drawbacks like the difficulty to discharge the stored thermal load which limits the system’s cyclability or their low thermal conductivity which limits their heat transfer capacity. To solve the problem of the PCM regeneration, an additional active system can be added, dimensioned on a moderate power; the whole becomes a semi-passive system. In this study, a thermal management system composed of a PCM and forced air convection is evaluated. This system permits to combine the respective advantages of the two techniques. A model of the system is developed for one battery cell. A comparison with forced air convection only points out the usefulness of the PCM. To overcome the PCM low thermal conductivity, a highly conductive material can be added to the PCM permitting to obtain a composite with a higher thermal conductivity. Composites based on the PCMs studied and carbon nanostructures are elaborated, and their thermal conductivity is measured. Then, an experimental system permitting to simulate the dissipation of a battery cell is build and used to evaluate the PCM alone, the PCM embedded in metal foam and the better obtained composite. Finally, to be closer to the real conditions, a model representing an entire battery stack is developed, simulations are produced and the obtained results are discussed

The diploma thesis is elaboration of project documentation of the object Housing for seniors in Brno - Dolní Heršpice. The site is located un the area with the planned development of the city. The object is detached, three-story with a partial basement. The building is divided into five parts. The building is based on concrete foundation pads and strips. The structural construction is a combined column and wall system in technological design as monolithic concrete. The building is designed as a low energy building, with contact insulation (ETICS). The whole building is designed with forced air exchange. An extensive and intensive walkable flat roof is designed. The aim is to create small, barrier-free, community housing with affordable services and support, with a possible life expectancy. Services for the elderly with reduced self-sufficiency and with mild health and mental dysfunctions are considered. The building is equipped with space for accommodation with a capacity of 48 beds, space for eating with a separate kitchen, space for leisure and physical activities, space for basic health and social care and space for administrative and technical facilities. The construction is divided into several buildings, the subject of the thesis is primarily the solution SO.01 - Housing for seniors

碩士
國立聯合大學
機械工程學系碩士班
106
There’s an increasing demand for linear platform in industry, while the system response speed and positioning accuracy requirements are also rising. The ironless linear motor has the characteristics of direct drive, so the response speed is fast. Because it does not have a cogging structure, so it has small speed ripple, and high positioning accuracy. However, due to continuous improvement of industrial technology, in addition to the requirements of the platform system more stringent, but also take into account the equipment usage and cost. So to enhance the motor thrust density is the key issue in motor design. This paper proposes an ironless linear motor with a forced air cooling at a safe operating temperature, and considers the coil winding density and the cooling efficiency of the air cooling system. Through this design method, the motor has the characteristics of high response, high precision and high thrust density. In addition to propose a design process in this paper, the electromagnetic field analysis (Ansys Maxwell), structural field analysis (Ansys Mechanical), and heat flow analysis (Fluent) are used to design an ironless linear motor with forced Air-cooling system and complete its prototype. Finally, the feasibility of the design is verified by experiment and simulation. Keywords: Ironless linear motor, thrust density, cooling system

碩士
華夏科技大學
資產與物業管理系
107
In recent years, Taiwan have serious air pollution because of thermal power plants 、 The Sixth Naphtha cracking plant (Six Naphtha)、factory、 motor vehicle exhaust and Chinese smog..., which cause a decrease in air quality. Especially for the matter PM2.5 Over standard most seriously affects peoples health. Not only Taiwan facing serious problems of PM2.5 over standard, but also many major cities have the same problem all over the world. Due to the poor outdoor air quality, the indoor air quality is not good, and about 80-90% of the time per person per day is located in the indoor environment. There have been many cases in recent years because the air in the decor contains formaldehyde and cause cancer, so attention should be paid to the health effects of indoor air pollutants. How to effectively monitor, manage and improve indoor air quality is an important topic of global concern. The purpose of this study is to explore a clean system for intelligent indoor air quality and to establish a new multi-functional formaldehyde purification treatment method. According to government regulations: intelligent air quality monitoring and management system, you can instantly monitor air quality, including: carbon dioxide, carbon monoxide, formaldehyde, total volatile organic compounds, PM10, PM2.5, ozone, etc. The air quality control system is automatically activated when it is detected that the above listed items exceed the legal standards. Including: air purifier (integrated primary filter - HEPA filter - medium steel activated carbon - US RGF-inside components - negative ion generator), can be formaldehyde, total volatile organic compounds, PM10, PM2.5 and other harmful gases, Bacteria and fungi are eliminated, and started a mechanical fresh air system is also introduced to introduce outside clean air to the room to rapidly reduce the concentration of carbon dioxide, carbon monoxide, ozone, etc., to legal standards. Establishment: The new multi-functional formaldehyde purification treatment method, by using PHI technology and Bi-Polar technology to completely decompose the volatilized formaldehyde, VOCs and harmful substances. Then use the patented "chitin" coated on the surface of the pollution source (for example: decoration materials or furniture), which can capture, adsorb and react in harmful gases, and break down the formaldehyde remaining in the decoration material into water molecules to complete the formaldehyde the effect of complete governance. This study is aimed at the actual testing of air quality in commercial buildings, hospitals, activity centers, nursing homes and homes. We compare the data of intelligent air quality purification system and new multi-functional formaldehyde purification treatment method before and after started, which proves that it can effectively purify the air. At the same time, the system can be combined with intelligent management system to integrate monitoring humidity, temperature, control dehumidifier and air conditioning is used to create the best indoor air quality. Key words：Property Management, Indoor air quality, Formaldehyde, PM2.5, Intelligent Air Purification System.

碩士
國立勤益科技大學
冷凍空調系
102
This study constructed a heat recovery and photocatalyst integration air purification system in a residence. Releasing some liquid volume of aromqtic or furniture detergent into the house to generate indoor VOC sources .Besides, one or two persons act in the house in order to accumulate the CO2 concentration in the house .While CO2 sensors detect the CO2 concentration in the house exceeding the recommend indoor standard value, the total heat exchanger is activated by a controller to induce outdoor fresh air and remove the indoor pollute air with a suitable flow rate. While TVOC sensors detect the VOC concentration in the house exceed the recommend standardvalue , the TiO2 photocatalyst air purification system is actived in order to degrade the indoor VOC concentration effectively .

碩士
明志科技大學
環境與資源工程研究所
100
Gaseous organic pollutants in the air, the removal techniques, including: adsorption, photocatalyst and ozonation, etc., However, because of its treatment effectiveness or side effects to the environment still different hazards or disadvantages, therefore, the application is limited and can’t be universal. This study intends to adopt VUV lamps produce 253.7nm and 185nm wavelength characteristics, so that in the humid air play "O3/UV/H2O" synergistic effects, the use of hydroxyl radical to degradation formaldehyde contamination of indoor air in order to improve the poor performance at low concentrations, while high concentrations harmful to the environment such as missing in the traditional ozone oxidation. In addition, it can be reduce the high cost of materials and maintenance costs for treatment technology of adsorption and photocatalyst. Expect to be a favorable choice as an alternative for the effective removal of organic pollutants in indoor air. In this study, "purify indoor air quality simulation test box" was designed in the laboratory, test cabinets installed in the vacuum ultraviolet, using its advanced oxidation technologies of "O3/UV/H2O" synergistic effects. For different airflow velocity (0.1m/s, 0.5m/s, 1m/s), different initial concentrations of pollutants (1ppm, 5ppm, 10ppm), the number of different lamps (6, 12, 24) as well as different arrangement may Lamp (radial horizontal, perpendicular to the radial, axial) and other conditions, a series of experiments were conducted to investigate the removal or degradation of performance of formaldehyde. Preliminary research results are as follows: (1)When the energy is insufficient for purification equipment, VUV lamp for formaldehyde degradation rate α(%), degradation β(mg/m3s), unit energy consumption degradation rate η(mg/m3W) and other performance is not related with different initial concentrations of pollutants, different flow rate, lamp test parameters such as different arrangement. (2)When purification equipment capable of handling capacity, UV lamp for formaldehyde degradation rate α(%), degradation β(mg/m3s) and other performance is low-relationship with lamp different arrangement. (3)VUV lamp for formaldehyde degradation rate α(%) is negative correlation with different initial concentrations of pollutants and different air velocity, and at a certain flow velocity(0.5m/s) conditions, VUV lamp for formaldehyde degradation β(mg/m3s) is positively related to response with different flow rate. (4)At a certain flow velocity(≦0.5m/s) under the conditions, handling the initial concentration of 1ppm formaldehyde contamination, 12 VUV lamp unit energy consumption degradation rate η(mg/m3W) is better than 24 VUV lamps, and when the processing of the initial concentration of 5ppm formaldehyde contaminants, 24 VUV lamp unit energy consumption degradation rate η(mg/m3W) is better than 12 VUV lamps. (5)The air flow velocity of 1m/s under the conditions, from the views of different initial concentrations of pollutants, the number of different lamps and other lamps different arrangement, VUV lamp is almost impossible to play the formaldehyde degradation effect, shows "O3/UV/H2O" synergy promoting effect, if applied to pipe purge, it will affect the flow rate control is an important factor in the effectiveness of the degradation. Keywords：Vacuum ultraviolet light (VUV), indoor air quality, formaldehyde.

碩士
逢甲大學
化學工程研究所
82
To emphasize the importance of the functions of thermal swing adsorption system in fixed beds on both air purification and solvent recovery, the system cyclic behavior includes not only the purification efficiency of the process air but also the enhancement ratio of the regeneration gas. For a specified adsorbate-adsorbent pair at a specified inlet temperature and concentration, the dimensionless parameters of the model affecting the system cyclic behavior include the dimensionless heat and mass transfer parameters and the dimensionless operating parameters, which are mainly functions of the transport properties and the operating conditions. In the study, the theoretical analysis was performed for a single component system to establish the relationship between the cyclic behavior and the dimensionless parameters, i.e. the so called dimensionless cyclic behavior chart in which the ordinate represents the cyclic behavior and the abscissa represents the operating cost. Each curve on the chart was formed at a specified purification efficiency and the lowest point of the curve can be taken as the optimal operating point of the system at this purification efficiency. Also, this optimal operating point was used as a criterion to select the optimal design and operating parameters in several case studies. Taking the acetone-activated carbon system as an example, the simulation results showed that the addition of a cooling step into the system can only improv1;the enhancement ratio of the regeneration gas a little and the enhancement ratio is about∼ 2.5 for the base point of the simulation , where the purification efficiency of the process air is set at 95%. The enhancement ratio of the system can be futher increased by decreasing the inlet concentration of the process air, increasing the inlet temperature of the regeneration gas, decreasing the purification efficiency of the process air, improving the mass transfer rates within the particles, and increasing the bed length.