Academic literature on the topic 'Varying area duct'

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Journal articles on the topic "Varying area duct"

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Krpenský, A., M. Bednařík, and J.-P. Groby. "Willis couplings in continuously varying cross-sectional area duct." Journal of the Acoustical Society of America 154, no. 3 (2023): 1660–66. http://dx.doi.org/10.1121/10.0020849.

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Acoustic wave propagation in a one-dimensional periodic and asymmetric duct is studied theoretically and numerically to derive the effective properties. Closed form expressions for these effective properties, including the asymmetric Willis coupling, are derived through truncation of the Peano–Baker series expansion of the matricant (which links the state vectors at the two sides of the unit-cell) and Padé's approximation of the matrix exponential. The results of the first-order and second-order homogenization (with Willis coupling) procedures are compared with the numerical results. The secon
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Asima, M., A. E. Amos, and Y. P. Olisa. "COMPUTATIONAL FLUID DYNAMICS ANALYSIS OF ADIABATIC FLUID FLOW IN GRADUALLY CONTRACTING TRANSITION DUCTS." Continental J. Engineering Sciences 10, no. 2 (2015): 21–27. https://doi.org/10.5281/zenodo.2936205.

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Computational fluid dynamics (CFD) was used to simulate fluid flow in ducts of varying diameters. Three Transition ducts of equal inlet areas but different outlet diameters were designed and analyzed. Fluid (water) with inlet velocity of 0.12m/s and temperature of 150 C (288.15K) was passed adiabatically through the first transition duct of inlet diameter 11.28mm and outlet diameter of 3.57mm. The analyses of the flow reveals a change of approximately 0.1K (-273.05) in temperature in the first duct while the other two ducts also have the same amount of temperature change because of the adiabat
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Yule, A. J., and M. Damou. "Axisymmetric turbulent jet flows in a duct of varying area." Experimental Thermal and Fluid Science 5, no. 4 (1992): 499–505. http://dx.doi.org/10.1016/0894-1777(92)90036-5.

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Kim, Dohaeng, and Wonju Jeon. "Acoustic metaliners for insulating noise in a duct with varying cross-sectional area." Journal of the Acoustical Society of America 154, no. 4_supplement (2023): A187. http://dx.doi.org/10.1121/10.0023217.

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We propose a sound-insulating acoustic metaliner for a duct with varying cross-sectional area with consideration of the flow that varies along the direction of flow and is not a fully-developed. The metaliner comprises an array of unit cells based on two different types of Helmholtz resonators and installed on the duct wall to preserve ventilation performance. To consider the effect of flow on the sound insulation performance of the metaliner, we establish an effective impedance model in term of the friction velocity, enabling the consideration for flows that are not fully-developed. The geome
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Tsai, Chih-Hsin, Shuhn-Shyurng Hou, and Ta-Hui Lin. "Spray flames in a one-dimensional duct of varying cross-sectional area." International Journal of Heat and Mass Transfer 48, no. 11 (2005): 2250–59. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2004.12.021.

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Xiao, Yongxiong, Huancai Lu, D. Michael McFarland, Lawrence A. Bergman, and Daren Zhou. "Analytical Solutions for Side-branch Impedance Producing Spatial Localization of Acoustic Waves in Ducts with Varying Cross Sections." International Journal of Acoustics and Vibration 26, no. 2 (2021): 132–38. http://dx.doi.org/10.20855/ijav.2021.26.21750.

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Analytical mathematical models and solutions for spatial localization of acoustic waves through an impedance discontinuity produced by an intermediate damped side branch are studied in stationary media in ducts with varying cross sections. Three specific geometries, namely, with polynomial, sinusoidal, and exponential longitudinal variations, are investigated. The sound fields inside the ducts are modeled by Webster's horn equation. Traveling-wave solutions are obtained by appropriate transformations. The side-branch impedances required for spatial localization (confinement) of traveling and s
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Pillai, Minu A., D. D. Ebenezer, and Ezhilarasi Deenadayalan. "Transfer matrix analysis of a duct with gradually varying arbitrary cross-sectional area." Journal of the Acoustical Society of America 146, no. 6 (2019): 4435–45. http://dx.doi.org/10.1121/1.5139412.

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Tsai, Chih-Hsin, Shuhn-Shyurng Hou, and Ta-Hui Lin. "A spray flame propagating in a nonadiabatic duct with varying cross-sectional area." Combustion and Flame 144, no. 1-2 (2006): 277–88. http://dx.doi.org/10.1016/j.combustflame.2005.08.006.

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Yang, Huanxin, Junjie Shi, Lin Chen, et al. "A Study of the Effects of Stimulants on Resin Yield, Resin Duct and Turpentine Chemical Composition in Pinus kesiya var. langbianensis." Forests 15, no. 5 (2024): 748. http://dx.doi.org/10.3390/f15050748.

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This study presents a comprehensive examination of Pinus kesiya var. langbianensis (Pinus kesiya var. langbianensis), the primary resin-extraction tree species in Yunnan Province, China. In this study, we formulated different concentration gradients of 0.25%, 0.5%, 1%, and 2% of diquat solution as tapping stimulant to test the effect of different concentrations on the resin gain rate of Pinus kesiya, and analyzed the relationship between anatomical structure, major chemical composition of turpentine and resin yield by methods such as wood anatomy and chemical composition analysis of turpentine
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Demir, A. "A Study of Air-Jet Texturing Nozzles: The Effects of Nozzle Configuration on the Air Flow." Journal of Engineering for Industry 112, no. 1 (1990): 97–104. http://dx.doi.org/10.1115/1.2899301.

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A thorough investigation of the existing texturing nozzles will, no doubt, lead to the design of improved nozzles. This paper reports the experimental research carried on the scaled-up versions of the T100 HemaJet with varying geometrical configurations, being the exit shape, situation, and inclination of the inlet holes, and the ratio of the incoming holes area to the nozzle’s main duct area. It has been found that the exit shape has virtually no effect on the airflow whilst other parameters contribute to the formation of the emerging jet which performs the texturing.
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Dissertations / Theses on the topic "Varying area duct"

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Tsai, Chih-Hsin, and 蔡志信. "Extinction of Dilute Spray Flames in a Duct with Varying Cross-Sectional Area." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/69280502322416869451.

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博士<br>國立成功大學<br>機械工程學系碩博士班<br>93<br>Abstract  The influences of flame stretch, preferential diffusion, internal heat transfer and external heat loss on the extinction of dilute spray flames propagating in a duct with varying cross-sectional area are analyzed using activation energy asymptotics. A completely prevaporized mode and a partially prevaporized mode of flame propagation are identified. The internal heat transfer, which results from droplet gasification and varies with the liquid fuel loading and the initial droplet size of the spray, provides internal heat loss for rich sprays but hea
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Books on the topic "Varying area duct"

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Campbell, Josie P. Student Companion to Zora Neale Hurston. Greenwood Publishing Group, Inc. www.greenwood.com, 2001. http://dx.doi.org/10.5040/9798216020448.

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Zora Neale Hurston is considered one of the most controversial yet prominent figures associated with the Harlem Renaissance. This introductory study examines Hurston's contributions to that literary movement, as well as her role as mediator between the black and white worlds in which she lived. Readers will appeciate the clear presentation of the biographical facts of her life, as well as an overview of the issues and varying perceptions surrounding her literary achievements. A full chapter is devoted to analysing each of Hurston's major works of fiction: Jonah's Gourd Vine (1934), Their Eyes
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Book chapters on the topic "Varying area duct"

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Suresh, A. "The Propagation of a Normal Shock in a Varying Area Duct." In Lecture Notes in Engineering. Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83695-4_18.

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Ghosh, Sandip, Allen Vivian Lakra, Suraj Gazi, Suvankar Debnath, Santanu Ghosh, and Abir Mukherjee. "LEAK FLOW ANALYSIS THROUGH NARROW CRACKS FROM HIGHPRESSURE PIPELINE MATERIALS." In Proceedings of International Conference on Engineering Materials and Sustainable Societal Development [ICEMSSD 2024]. Iterative International Publishers (IIP), Selfypage Developers Pvt Ltd., 2025. https://doi.org/10.58532/nbennuricemssd21.

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The occurrence of cracks in high-pressure duct systems is common and proven to be hazardous for various power and process plants. Safety issues are driven by piping design methodology and loss of coolant accident scenario especially in nuclear power stations. The present work analyses the leak flow through narrow circumferential cracks on stainless steel pipes of predefined geometry at varying high pressure water conditions and different areas of crack openings using computational simulation methods. The results of this analysis showcase the behaviour of leak flow properties flowing through th
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Rajshekhar Gopal Rathod, Dr, Aishwarya P. Gayakawad, and Sagar Sonawane. "BLACK COTTON SOIL STABILIZATION BY USING BIO-ENZYME AND MARBLE DUST POWDER FOR PAVEMENT SUB-GRADE." In Futuristic Trends in Construction Materials & Civil Engineering Volume 3 Book 4. Iterative International Publishers, Selfypage Developers Pvt Ltd, 2024. http://dx.doi.org/10.58532/v3bice4p4ch5.

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Black Cotton Soils (BCS) pose challenges due to their susceptibility to vertical ground movements, particularly affecting Geotechnical Structures and Pavement. These issues are exacerbated in areas with poor subgrade soil, where pavement construction becomes prohibitively expensive. To address this, there's a growing shift towards exploring non-traditional, sustainable, and cost-effective alternatives. Despite this need, research on the reaction mechanisms of non-traditional soil stabilization methods is limited. In this context, the study explores the use of Marble Dust (MD) as a soil stabili
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Gutierrez, Yezid. "Biliary And Pancreatic Trematodes." In Diagnostic Pathology of Parasitic Infections with Clinical Correlations. Oxford University PressNew York, NY, 1999. http://dx.doi.org/10.1093/oso/9780195121438.003.0024.

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Abstract The trematodes of the biliary and pancreatic ducts of humans belong to three families: Fasciolidae, Opistorchiidae, and Dicrocoeliidae. Fasciolidae includes Fascia/a hepatica, which is endemic worldwide, producing important morbidity in certain geographic areas, and F. gigantica, with a more restricted distribution. The members of Opistorchiidae are widely distributed, producing a large number of infections but generally with low morbidity. Finally, the members of Dicrocoeliidae have species that usually occur in humans as sporadic zoonotic infections. All species in these families ha
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"Morphological characteristics of fine air particulate matter collected in the suburban area." In Book of Abstracts - RAD 2025 Conference. RAD Centre, Niš, Serbia, 2025. https://doi.org/10.21175/rad.abstr.book.2025.11.5.

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The air quality monitoring in both urban and rural areas has revealed the ambient particulate matter as the most harmful airborne pollutant for human health while in addition to the particle composition, their size and shape are crucial for the behavior in the body. Here are presented results of the physical-chemical characterization of the submicron particles collected at the Belgrade suburban monitoring site Zeleno Brdo. Daily (24h) samples were collected by Leckel reference samplers on the polytetrafluoroethylene (PTFE) 47 mm filters in four seasons 2018/19. Particulate matter with submicro
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Kumar, Bhavan, Venkatesha Raju K, and Jagdish H. Godihal. "Investigation on Removal of Fluoride in Water using Natural Materials." In Frontiers of Advancements in Materials | IoT | Drones | and Innovations in Construction Environment | and Infrastructure. Iterative International Publishers, Selfypage Developers Pvt Ltd, 2024. http://dx.doi.org/10.58532/nbennurfach14.

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The current study focuses on assessing the efficiency of a natural treatment unit that uses tamarind flakes, sawdust, Tulsi, and fragmented bricks to eradicate fluoride in water. The study aims to determine the optimal conditions for fluoride removal in water using these natural materials and to appraise the effectiveness of the treatment unit. The study involves laboratory experiments using synthetic water sample with known fluoride concentration of 18.4mg/L. The natural treatment unit was constructed using tamarind flakes, sawdust, Tulsi and fragmented brick in different containers. Two diff
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Conference papers on the topic "Varying area duct"

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Singh, Rajneesh, Benjamin Jimenez, and Michael Avera. "Investigation of Aerodynamic Interactions in Ducted Rotor Systems." In Vertical Flight Society 70th Annual Forum & Technology Display. The Vertical Flight Society, 2014. http://dx.doi.org/10.4050/f-0070-2014-9431.

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Computational analysis of a ducted rotor system is performed to investigate aerodynamic interactions of a rotor with a duct in hover. It is hypothesized that the duct contribution to the total system thrust in hover will be higher if the rotor inflow is higher in the blade tip region because of lower pressure on the duct inlet. Thus the optimum inflow requirements for a ducted rotor are different than for an open rotor. Two approaches of varying fidelity are considered. Rotor thrust performance for a rotor containing different radial blade twist distributions is analyzed as both an open and du
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McDonald, James, and Pablo L. Bernad. "Activated Zinc Technology; Making Zinc-Rich Epoxies Work Better for the Applicator and the Owner." In SSPC 2016 Greencoat. SSPC, 2016. https://doi.org/10.5006/s2016-00044.

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Abstract Inorganic zinc-rich coatings (IOZ’s) are often considered the gold standard for corrosion protection in atmospheric environments. Frequently, zinc epoxy coatings are considered second best among the most effective coatings for corrosion protection. However, current zinc-rich coating technology is not exempt of limitations, such as poor mechanical properties of the film, rigid environmental application conditions, or the inefficient use of zinc particles for providing galvanic protection. Due to these limitations, a number of asset owners have made the decision not to use zinc-rich coa
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Gaur, Ritesh, Vimala Narayanan, and S. Kishore Kumar. "Influence of Area Distribution With Fixed Trajectory on Serpentine Intake Duct Performance." In ASME 2012 Gas Turbine India Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gtindia2012-9625.

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Performance of intake duct with fixed inlet trajectory and different area distributions have been analyzed using a commercial CFD (Computational Fluid Dynamics) software. The performance have been evaluated for fixed boundary conditions. The area distributions studied are defined by varying cross sectional area at different locations of intake duct by keeping the inlet and exit area same. The performance of the intake ducts are studied in terms of the pressure recovery coefficient, total pressure loss, pressure recovery factor and distortion coefficient in the present work. The motion caused b
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Zhang, Yanfeng, Shuzhen Hu, Ali Mahallati, Xue-Feng Zhang, and Edward Vlasic. "Effects of Area Ratio and Mean Rise Angle on the Aerodynamics of Inter-Turbine Ducts." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-27207.

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The present work, a continuation of a series of investigations on the aerodynamics of aggressive inter-turbine ducts (ITD), is aimed at providing detailed understanding of the flow physics and loss mechanisms in four different ITD geometries. A systematic experimental and computational study was carried out for varying duct mean rise angles and outlet-to-inlet area ratio while keeping the duct length-to-inlet height ratio, Reynolds number and inlet swirl constant in all four geometries. The flow structures within the ITDs were found to be dominated by the counter-rotating vortices and boundary
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Mateer, J. C., A. M. Birk та D. Poirier. "Computational Comparison of an Air-Air Ejector System Utilizing a Primary S-Bend Transition Duct Employing the Realizable k-ε Turbulence Model". У ASME Turbo Expo 2005: Power for Land, Sea, and Air. ASMEDC, 2005. http://dx.doi.org/10.1115/gt2005-68657.

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A computational study of an air-air ejector system, utilizing a primary S-bend transition duct, was compared with experimental results. Two primary ducts, differing in offset, consisted of an annular-to-circular-to-oblong transition which incorporated a total area increase of 62.4% with the duct performing 16% diffusion. The ducts were analyzed both alone and in ejector configuration under varying degrees of inlet swirl. The ejector geometry consisted of the duct with a downstream mixing tube. Several mixing tubes, of oblong cross sectional shape, differing in both length and area, were tested
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R, Sadham Usean, Prasad B. V. S. S. S., Milind Dhabade, Amit Kurvinkop, and Vishnuvardhan Tatiparthi. "Design of Duct Passages for an Air Turbine Starter Test Rig." In ASME 2021 Gas Turbine India Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/gtindia2021-76152.

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Abstract In a typical air turbine starter (ATS) engine testing application, compressed air is supplied to the turbine by means of an inlet duct usually with a 90 degree bend and discharged from the turbine into the exhaust chimney through a combination of two duct passages. The primary duct is integral to the engine for connecting to the containment ring. The secondary duct is a transition piece for connecting to the exhaust chimney. As these ducts consume additional pressure and adversely affect the performance of the ATS under test. The design of pressure-efficient outlet ducts is therefore
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Gillespie, John, and K. Todd Lowe. "Non-Circular and Non-Cylindrical Streamvanes." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-15763.

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Abstract We show that desired swirl distributions may be obtained in non-circular and non-cylindrical inlet ducts by tailored vane distributions designed with an a priori method, and further explain dominant physics for the spatial evolution of swirl in expanding or contracting ducts. Virginia Tech has developed the StreamVane™ device for producing swirl distortion, as well as the ScreenVane™ device for producing combined swirl and pressure distortions. Up to now, all StreamVane and ScreenVane devices have designed to fit in a right, circular cylindrical duct. This is usually the simplest geom
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Sterzinger, P. Z., S. Zerobin, F. Merli, et al. "Impact of Varying High- and Low-Pressure Turbine Purge Flows on a Turbine Center Frame and Low-Pressure Turbine System." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90795.

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Abstract This paper presents the experimental and numerical evaluation and comparison of the different flow fields downstream of a turbine center frame duct and a low-pressure turbine stage, generated by varying the inlet flow conditions to the turbine center frame duct. The measurements were carried out in an engine-representative two-stage two-spool test turbine facility at the Institute for Thermal Turbomachinery and Machine Dynamics at Graz University of Technology. The rig consists of a high-pressure (HPT) and a low-pressure (LPT) turbine stage, connected via a turbine center frame (TCF)
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Schueren, Simon, Florian Hoefler, Jens von Wolfersdorf, and Shailendra Naik. "Heat Transfer in an Oblique Jet Impingement Configuration With Varying Jet Geometries." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45169.

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Experimental and numerical heat transfer results in a trapezoidal duct with two staggered rows of inclined impingement jets are presented. The influence of changes in the jet bore geometry on the wall heat transfer is examined. The goal of this project is to minimize the thermal load in an internal gas turbine blade channel and to provide sufficient cooling for local hot spots. The dimensionless pitch is varied between p/djet = 3–6. For p/djet = 3, cylindrical as well as conically narrowing bores with a cross section reduction of 25% and 50%, respectively, are investigated. The studies are con
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Dodwad, Abhishek, Prasanna V. Nagarhalli, Sunil Fartade, and Uttam Namdeo Ahire. "Improvement of AC System for Bus with Tropical/Hot Ambient Application." In SAENIS TTTMS Thermal Management Systems Conference-2023. SAE International, 2023. http://dx.doi.org/10.4271/2023-28-0016.

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&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;AC system provides the human comfort inside the cabin of a vehicle but at the expense of consumption of energy from the vehicle. On a global perspective for the bus segment, there is an increased demand for cooling in tropical countries. Optimization needs to be done in existing AC systems w.r.t packaging, cost &amp;amp; performance constraints. Major elements contributing to heat ingress are engine hood, front firewall, windshield &amp;amp; side glasses and bus body parts. Due to these reasons inadequate passenger comfo
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Reports on the topic "Varying area duct"

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Renaud, Alexander, Michael Forte, Nicholas Spore, et al. Evaluation of Unmanned Aircraft Systems for flood risk management : results of terrain and structure assessments. Engineer Research and Development Center (U.S.), 2022. http://dx.doi.org/10.21079/11681/45000.

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The 2017 Duck Unmanned Aircraft Systems (UAS) Pilot Experiment was conducted by the US Army Engineer Research and Development Center (ERDC), Coastal and Hydraulics Laboratory, Field Research Facility (FRF), to assess the potential for different UAS to support US Army Corps of Engineers coastal and flood risk management. By involving participants from multiple ERDC laboratories, federal agencies, academia, and private industry, the work unit leads were able to leverage assets, resources, and expertise to assess data from multiple UAS. This report compares datasets from several UAS to assess the
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Kim, Lauren Nicole, Katherine Brodie, Nicholas Cohn, Sarah Giddings, and Mark Merrifield. Observations of Beach Change and Runup, and the Performance of Empirical Runup Parameterizations during Large Storm Events. Engineer Research and Development Center (U.S.), 2024. http://dx.doi.org/10.21079/11681/48712.

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Timeseries observations of beach elevation change and wave runup from a tower-mounted stationary lidar assess the skill of 2% runup exceedance (𝑅𝑅2%) estimates during four storm events at Duck, NC. The runup parameterization requires the foreshore beach slope, which generally unknown during high energy events. Pre-storm estimates are often used as a proxy. 𝑅𝑅2% hindcasts use the observed time-varying beach slope and a static pre-storm beach profile, yielding an 𝑅𝑅2% skill of 0.57. The skill drops to −1.0 using seasonal mean beach slopes and reduces after the peak of two storms with the appeara
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