Relevant bibliographies by topics / Fluide hfc 134a

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  2. Dissertations / Theses
  3. Conference papers

Academic literature on the topic 'Fluide hfc 134a'

Author: Grafiati
Published: 4 June 2021
Last updated: 13 February 2022

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Journal articles on the topic "Fluide hfc 134a"

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Hasheer, Shaik Mohammad, and Kolla Srinivas. "Performance Comparison of a Low GWP Refrigerants as Alternatives to R134a in a Refrigerator with and without Liquid-Suction Heat Exchanger." Materials Science Forum 969 (August 2019): 343–48. http://dx.doi.org/10.4028/www.scientific.net/msf.969.343.

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The usage of refrigerators and air conditioners are more prevalent in a domestic environment now-a-days. Improving the efficiency of these devices can be considered as an important step to reduce their energy consumption. Currently, in India, most refrigerators work with HFC-134a as a refrigerant. The GWP value of HFC-134a is around 1430.Therefore, there is a greater demand to replace HFCs with low GWP refrigerants. In this document, the comparison of the performance of a refrigerator without fluid intake heat exchanger (LSHX) with low GWP refrigerants and the results are compared with HFC-134a performed. The low GWP refrigerants used in the test are: hydrocarbon-propane (R290) and isobutane (R600a), the pure hydrocarbons are HFC-134a and HFC-152a and the refrigerants are hydrofluoroolefins 1234yf and 1234ze (E). All have been tested without making changes in the system. The entire examination was carried out in the same system under the same working conditions.
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Tsvetkov, Oleg B., Igor V. Baranov, Yuriy A. Laptev, Alexander V. Sharkov, Vladimir V. Mitropov, and Alexey V. Fedorov. "Third Generation of Working Fluids for Advanced Refrigeration Heating and Power Generation Technologies." Key Engineering Materials 839 (April 2020): 51–56. http://dx.doi.org/10.4028/www.scientific.net/kem.839.51.

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Since the 1987 Montreal Protocol, chlorinated refrigerants (CFCs and HCFCs) have been pointed out as responsible for the destruction of the ozone layer. The chemical industry has realized suitable replacement for CFC-12 and for HCFC-22 e.g. HFC-134a, HFC-404A, HFC-410A, HFC-507. This generation of refrigerants developed by the chemical industry can be characterized by the no ozone depleting potential and long atmospheric lifetime resulting in global warming potential. The contribution of the HFCs to the global warming brings up to discussion whether the HFCs should be considered as a transitional substance. Historically the use of natural and ecologically safe refrigerants was a strategy to eliminate environmental problems and avoid uncertainties with synthetic replacement fluids. Since ammonia is toxic, carbon dioxide provide high pressure, and the hydrocarbons are flammable, the general conclusion is often drawn that natural fluids gave safety problems. This paper will describe the possibilities of application as working fluids in low-temperature engineering refrigeration, heat pumping and organic Rankine cycles of the hydrofluoroolefins (HFOs) as third generation of synthetic working fluids.
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Abbott, Andrew P., Christopher A. Eardley, and James E. Scheirer. "CO2/HFC 134a mixtures: alternatives for supercritical fluid extraction." Green Chemistry 2, no. 2 (2000): 63–66. http://dx.doi.org/10.1039/a907683b.

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Liu, Zhao-Tie, Jin Wu, Ling Liu, et al. "Solubilities of AOT Analogues Surfactants in Supercritical CO2and HFC-134a Fluids." Journal of Chemical & Engineering Data 51, no. 5 (2006): 1761–68. http://dx.doi.org/10.1021/je0601659.

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PIAO, Chun-cheng, Haruki SATO, and Koichi WATANABE. "An Equation of State for a New Working Fluid HFC-134a." Transactions of the Japan Society of Mechanical Engineers Series B 57, no. 544 (1991): 4182–89. http://dx.doi.org/10.1299/kikaib.57.4182.

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Nilpueng, Kitti, and Somchai Wongwises. "Choked flow mechanism of HFC-134a flowing through short-tube orifices." Experimental Thermal and Fluid Science 35, no. 2 (2011): 347–54. http://dx.doi.org/10.1016/j.expthermflusci.2010.10.004.

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Nilpueng, Kitti, Chietta Supavarasuwat, and Somchai Wongwises. "Performance characteristics of HFC-134a and HFC-410A refrigeration system using a short-tube orifice as an expansion device." Heat and Mass Transfer 47, no. 10 (2011): 1219–27. http://dx.doi.org/10.1007/s00231-011-0783-y.

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Singh, Sanjeev, and Rajeev Kukreja. "Experimental Heat Transfer Coefficient and Pressure Drop during Condensation of R-134a and R-410A in Horizontal Micro-fin Tubes." International Journal of Air-Conditioning and Refrigeration 26, no. 03 (2018): 1850022. http://dx.doi.org/10.1142/s2010132518500220.

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Condensation heat transfer coefficients and pressure drops of HFC refrigerants R-134a and R-410A have been investigated experimentally in smooth and micro-fin tubes (helix angles 18[Formula: see text] and 15[Formula: see text]) of outer diameter 9.52[Formula: see text]mm at mass fluxes from 200 to 600[Formula: see text]kg/m[Formula: see text]s, vapor qualities between 0.1 and 0.9 and at saturation temperatures of 35[Formula: see text]C and 40[Formula: see text]C. Results showed that the heat transfer coefficients of R-134a and R-410A inside micro-fin tubes were 1.21–1.82 and 1.15–1.47 times higher and frictional pressure drops were 2.11–2.56 and 1.62–2.12 times higher than those of smooth tubes. These experimental results are compared with the existing heat transfer and frictional pressure drop correlations proposed by different researchers. The comparison showed fairly good agreement with these existing correlations within [Formula: see text]30%. A new correlation has also been proposed for predicting heat transfer coefficient in micro-fin tubes. The oil concentrations measured for refrigerants R-134a and R-410A varied in the range of 1.3–1.5%, respectively.
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García-Valladares, O., and E. Santoyo. "Numerical simulation and validation of HFC-134a fluid flow through short-tube orifices considering metastable conditions." Applied Thermal Engineering 62, no. 1 (2014): 267–76. http://dx.doi.org/10.1016/j.applthermaleng.2013.09.024.

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Chun, Se-Young, Sung-Deok Hong, Yeon-Sik Cho, and Won-Pil Baek. "Comparison of the CHF data for water and refrigerant HFC-134a by using the fluid-to-fluid modeling methods." International Journal of Heat and Mass Transfer 50, no. 21-22 (2007): 4446–56. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2005.06.039.

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Dissertations / Theses on the topic "Fluide hfc 134a"

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Yu, Yingzhong. "Approche générique des modes d'émissions de HFC-134a des systèmes de climatisation automobile." Phd thesis, École Nationale Supérieure des Mines de Paris, 2008. http://pastel.archives-ouvertes.fr/pastel-00004889.

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Les paramètres physiques à la base des fuites du fluide frigorigène HFC-134a dans les systèmes de climatisation automobile ne sont pas encore pleinement compris. Le but de ce travail de recherche est d'établir une méthode de mesures des débits de fuite de fluide frigorigène des systèmes de climatisation automobile ainsi que des composants de ces systèmes, et aussi de développer une approche générique de prévision de ces émissions. Dans la thèse, les fuites chroniques des différents composants des systèmes de climatisation automobile sont évaluées et hiérarchisées. Une méthode d'essais de laboratoire, basée sur la mesure de concentration dans un volume d'accumulation, est présentée pour déterminer les débits de fuite de systèmes et de composants. La précision de la mesure est aussi justifiée. Des mesures en régime permanent et pour plusieurs températures contrôlées sont effectuées afin de comparer le débit de fuite de l'ensemble du système et la somme des débits de fuite de tous les composants. Les simulations de la variation de température permettent de prédire les impacts des conditions climatiques annuelles quel que soit le climat. Les essais en régime dynamique sont également traités pour analyser la contribution du temps de fonctionnement du système aux émissions annuelles du système. Afin de vérifier la méthode d'essai en laboratoire, des opérations de récupération du fluide frigorigène ont été effectuées sur une quarantaine de véhicules avec une précision de +0 / -1 g. Sur la base des résultats des essais en laboratoire et de ceux obtenus sur la flotte de véhicules, un facteur de corrélation a été établi pour corréler les tests en laboratoire aux émissions mesurées sur le terrain. Les prévisions des émissions de tuyauteries flexibles utilisées dans les systèmes de climatisation automobile ont été développées en prenant en compte les effets de la température et de la pression. Les joints toriques typiques sont étudiés et deux modes de fuite: la perméation à travers des matériaux polymères et l'écoulement du gaz dans les micro-canaux sont distingués. Les performances d'étanchéité d'un joint torique radial sont étudiées en utilisant la méthode des éléments finis. Le comportement non-linéaire des déformations des polymères est pris en compte. L'analyse des facteurs principaux tels que la contrainte, la pression de contact maximale et le contact est basée sur les résultats de simulations numériques. Les deux modes de fuites permettent de comprendre les phénomènes clés des émissions et donc d'améliorer les performances d'étanchéité. En résumé, le débit de fuite d'un système de climatisation automobile est la somme des débits de fuite de toutes les sources de fuites. Ces sources sont de deux types: la perméabilité du gaz dans les polymères et l'écoulement du gaz dans les micro-canaux existant entre les joints et les parties métalliques des raccords. Pour chaque mode d'émission, une loi de comportement a été développée et les modèles prédictifs permettent de prévoir les débits de fuite avec un nombre limité de mesures.
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Signe, Jean-Christian. "Condensation de mélanges non azéotropes de fluides frigorigènes à l'extérieur d'un faisceau de tubes horizontaux." Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10064.

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L'utilisation de nouveaux fluides frigorigenes respectueux de notre environnement remet en cause les connaissances etablies pour le dimensionnement des installations frigorifiques et de conditionnement d'air. Certains de ces fluides - les melanges non azeotropes - presentent lors de leur condensation des particularites (condensation anisotherme, apparition d'une resistance au transfert de chaleur et de masse dans la phase gazeuse) qui rendent delicat le dimensionnement des condenseurs. L'etude experimentale de la condensation de fluide pur hfc134a et de differents melanges de hfc134a-hfc23 dans un condenseur de type tema x a permis de caracteriser les echanges de chaleur sur quatre types de tubes (un tube lisse et trois tubes a ailettes). Le coefficient d'echange du melange binaire hfc134a-hfc23 est tres different de celui du fluide pur hfc134a. La comparaison des donnees experimentales de la condensation du fluide pur avec les differentes correlations de la litterature a determine le choix le mieux adapte au dimensionnement des condenseurs de ce type. Les mesures effectuees lors de la condensation du melange non azeotrope ont ete confrontees a deux modeles classiques de la condensation de melange : le modele de la courbe d'equilibre et la theorie du film. Pour la modelisation du premier tube du faisceau, le modele de la courbe d'equilibre, pourtant plus simple, donne d'aussi bon resultats que la theorie du film. Par contre, les echanges de chaleur dans le faisceau lors de la condensation de melanges sont difficiles a prendre en compte avec les correlations classiques.
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Conference papers on the topic "Fluide hfc 134a"

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Javidmand, Puya, and Klaus A. Koffmann. "Numerical-Based Comparison Among Critical Flow Properties of HFC-134a and its New Alternatives HFO-1234yf and HFO-1234ze Through Short-Tube Orifices." In ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2015 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/icnmm2015-48048.

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Although HFC-134a is a common refrigerant for residential and mobile refrigeration systems, investigators are dealing with replacing it with new alternatives because of its harmful environmental and global warming effects. Recently HFO-1234yf and HFO-1234ze have been introduced as suitable alternative refrigerants because they have zero ozone depletion potential (ODP) and low global warming potential (GWP) and possess thermophysical properties similar to those of HFC-134a. Because there is no experimental data on the performance of these new refrigerants in capillary tubes and short-tube orifices, a recently developed numerical model for analysis of critical two-phase flow through these tubes is used to predict the critical mass flow rate and pressure distribution of HFO-1234yf and HFO-1234ze under various operating conditions. The applied numerical model is based on a comprehensive two-fluid model including the effects of two-phase flow patterns and liquid-phase metastability. The numerical method has been validated by comparing numerical results of the critical flows of HFC-134a, R-410A, and HCFC-22 with available experimental data. The developed numerical simulation is applied in order to develop comparison and selection charts for short-tube orifices based on the common refrigerant HFC-134a and the alternative new refrigerants HFO-1234yf and HFO-1234ze.
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Yaddanapudi, Satvik J., and Huseyin Bostanci. "Spray Cooling With HFC-134a and HFO-1234yf for Thermal Management of Automotive Power Electronics." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-52312.

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This study aimed to experimentally investigate the spray cooling characteristics for active two-phase cooling of automotive power electronics. Tests were conducted on a small-scale, closed loop spray cooling system featuring a pressure atomized spray nozzle. Two types of refrigerants, HFC-134a (R-134a) and HFO-1234yf, were selected as the working fluids. The test section (heater), made out of oxygen-free copper, had a 1-cm2 plain, smooth surface prepared following a consistent procedure, and served as a baseline case. Matching size thick film resistors, attached onto the copper heaters, generated heat and simulated high heat flux power electronics devices. The experiments were performed with saturated working fluids at room temperature level (22°C) by controlling the heat flux in increasing steps, and recording the corresponding steady-state temperatures to obtain cooling curves. Performance comparisons were made based on heat transfer coefficient (HTC) and critical heat flux (CHF) values. Effects of spray characteristics and liquid flow rates on the cooling performance were determined with three types of commercially available nozzles that generate full-cone sprays with fine droplets, and with varying flow rates between 1.6 to 5.4 ml/cm2.s. The experimental data showed that HFC-134a provided better performance compared to HFO-1234yf, in terms of HTC and CHF, which is believed to be dictated by the thermophysical properties that affect both the spray characteristics and heat acquisition ability. Overall, this study provided a framework for spray cooling performance with the current and next-generation refrigerants aimed for advanced thermal management of automotive power electronics.
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Hossain, Shekh N., and Saiful Bari. "Waste Heat Recovery From the Exhaust of a Diesel Generator Using Shell and Tube Heat Exchanger." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63080.

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The heat from exhaust gas of diesel engines can be an important heat source to provide additional power and improve overall engine efficiency. Bottoming Rankine Cycle (RC) is one of the promising techniques to recover heat from the exhaust. One derivative of RC known as Organic Rankine Cycle (ORC) is also suitable for heat recovery for moderate and small size engines as the exhaust heat content and temperature of these engines are low. To recover heat from the exhaust of the engine, an efficient heat exchanger is necessary. In this current research, a shell and tube heat exchanger is optimized by computer simulation for two working fluids, water and HFC-134a. Two shell and tube heat exchangers were purchased and installed into a 40 kW diesel generator. The performance of the heat exchangers using water as the working fluid was then conducted. With the available data, computer simulation was carried out using CFD software ANSYS CFX14.0 to improve the design of the heat exchanger for both fluids. Geometric variables including length, number of tubes, and baffle design are all tested separately. Using the optimized heat exchangers simulation was conducted to estimate the possible additional power generation considering 80% isentropic turbine efficiency. The proposed heat exchanger was able to produce 11% and 9.4 % additional power using water and HFC-134a as the working fluid at maximum working pressure of 15 and 40 bar respectively. This additional power results into 12% and 11% improvement in brake-specific fuel consumption (bsfc) by using water and HFC-134a respectively. This indicates that besides water, organic fluids can also be a suitable option to recover heat from the exhaust of diesel engine.
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Chun, S., S. Hong, N. Watanabe, S. Moon, and M. Aritomi. "EXPERIMENTAL STUDY ON HEAT TRANSFER OF 5X5 HEATER ROD BUNDLE WITH HFC-134A FLUID NEAR THE CRITICAL PRESSURE." In Annals of the Assembly for International Heat Transfer Conference 13. Begell House Inc., 2006. http://dx.doi.org/10.1615/ihtc13.p18.320.

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Bortolin, Stefano, Alberto Cavallini, Davide Del Col, Marko Matkovic, and Luisa Rossetto. "Flow Boiling of Refrigerants Inside a Single Circular Minichannel." In ASME 2008 6th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2008. http://dx.doi.org/10.1115/icnmm2008-62270.

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The present paper reports the heat transfer coefficients measured during flow boiling of HFC-32 and HFC-134a in a 0.96 mm diameter single circular channel. The test runs have been performed during vaporization at around 30°C saturation temperature, correspondent to 19.3 bar for R32 and 7.7 bar for R134a. As a peculiar characteristic of the present technique, the heat transfer coefficient is not measured by imposing the heat flux; instead, the boiling process is governed by controlling the inlet temperature of the heating secondary fluid. The quality of the inner surface of the test tube has been measured to check the influence of surface roughness on the heat transfer coefficient. The flow boiling data taken in the present test section is presented and discussed, with particular regard to the effect of heat flux, mass velocity, vapor quality and fluid properties.
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Patil, Pradeep A., and S. N. Sapali. "Experimental Apparatus for Measuring in Tube Condensation Heat Transfer Coefficient and Pressure Drop Using Smooth and Micro-Fin Tubes for HFC Refrigerants." In ASME 2008 Heat Transfer Summer Conference collocated with the Fluids Engineering, Energy Sustainability, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/ht2008-56029.

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An experimental test facility is designed and built to calculate condensation heat transfer coefficients and pressure drops for HFC-134a, R-404A, R-407C, R-507A in a smooth and micro-fin tube. The main objective of the experimentation is to investigate the enhancement in condensation heat transfer coefficient and increase in pressure drop using micro-fin tube for different condensing temperatures and further to develop an empirical correlation for heat transfer coefficient and pressure drop, which takes into account the micro-fin tube geometry, variation of condensing temperature and temperature difference (difference between condensing temperature and average temperature of cooling medium). The experimental setup has a facility to vary the different operating parameters such as condensing temperature, cooling water temperature, flow rate of refrigerant and cooling water etc and study their effect on heat transfer coefficients and pressure drops. The hermetically sealed reciprocating compressor is used in the system, thus the effect of lubricating oil on the heat transfer coefficient is taken in to account. This paper reports the detailed description of design and development of the test apparatus, control devices, instrumentation, and the experimental procedure. It also covers the comparative study of experimental apparatus with the existing one from the available literature survey. The condensation and pressure drop of HFC-134a in a smooth tube are measured and obtained the values of condensation heat transfer coefficients for different mass flux and condensing temperatures using modified Wilson plot technique with correlation coefficient above 0.9. The condensation heat transfer coefficient and pressure drop increases with increasing mass flux and decreases with increasing condensing temperature. The results are compared with existing available correlations for validation of test facility. The experimental data points have good association with available correlations except Cavallini-Zecchin Correlation.
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Sadek, Hossam S., James S. Cotton, Chan Y. Ching, and Mamdouh Shoukri. "Visualization of Flow Regime Transitions in Two-Phase Flow Under High Voltage Electric Fields." In ASME 2006 2nd Joint U.S.-European Fluids Engineering Summer Meeting Collocated With the 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/fedsm2006-98336.

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The effects of applying DC high voltage electric fields on two-phase flow regime transitions for flowing refrigerant HFC-134a were visualized using a high speed camera. The viewing test section was made of 10 mm inner diameter quartz tube with a 3.18 mm diameter charged electrode placed along the center of the tube. The quartz tube was coated with an electrically grounded transparent conductive film of Tin Oxide. The experiments were performed for mass flux (55 kg/m2s < G < 263 kg/m2s), quality (20% < x < 80%) and applied voltage (0 kV < V < 8 kV). The flow regime transitions depend on the flow regime prior to applying the EHD. For stratified flow, EHD increases the interfacial instabilities and causes liquid extraction to the upper section of the tube. When the flow regime is initially annular flow, EHD increases the uniformity of the annular film by extracting liquid from the thicker liquid regions into the vapor core.
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Javidmand, Puya, and Klaus A. Hoffmann. "Comprehensive Two Fluid Model Simulation of Critical Two-Phase Flow Through Short Tube Orifices." In ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2015 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/icnmm2015-48047.

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Small-diameter tubes are utilized widely as expansion devices in refrigeration systems. They are employed in either kinds of short-tube orifices or long capillary tubes. Performance of these tubes is reliant upon critical flashing of the two-phase flow that controls the mass flow rate of the refrigeration system resulting in a steep reduction in pressure and temperature. The critical flow condition is approached whenever the mass flow rate increases to an amount whereby the choked-flow phenomenon occurs at the outlet of the tube. Due to their very small tube diameter, the evaporating two-phase flow, and the choked-flow condition, numerical analysis of flow through short-tube orifices is challenging. Accordingly, all available numerical analyses of such flows are performed as one-dimensional and in the majority of them, auxiliary correlations are applied to simplify the solution procedure. Typical approaches include homogeneous flow models and separated flow models, both of which consider the two-phase region in thermal equilibrium. The most comprehensive method for analyzing such flows is the two-fluid model in which there is no assumption of equilibrium between phases. Because of the complicated nature of this model, it has been used in a very limited number of previous investigations. Furthermore, two-phase flow calculations at the entrance and vena contracta region were eliminated. In the current investigation, additional steps utilized to improve the accuracy of computations include the following: (1) applying the most comprehensive two-fluid model including the effect of various two-phase flow patterns and the metastability of liquid phase, and (2) performing a two-phase analysis of the evaporating flow through the entrance and vena contracta regions which involves simulating the region as a converging diverging tube and performing a quasi-one-dimensional solution of governing equations through this region. Results showed more compatibility with experimental data in comparison with those of previous investigations for predicting the critical flow condition of common refrigerants HFC-134a and HFC-410a through short-tube orifices and long capillary tubes.
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Liang, S. B., and G. P. Xu. "Effect of Thin Film Condensation on Thermal Performance of Oscillating Heat Pipes." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14129.

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Self-sustainable motions of the slug flow in oscillating heat pipes have been investigated in the paper. Thin film condensation in the capillary channels of the condenser of the oscillating heat pipes was studied. Instability of the thin liquid film on the characteristics of heat pipes was analysed. The extra thermal resistance caused by the thickness of the thin liquid film was taken into account for the numerical simulation of the oscillatory motions of the slug flow in the heat pipes. Saturated temperatures and pressures of the working fluid in the condenser were obtained. Thermoacoustic theory was applied to calculate heat transport through the adiabatic section of the heat pipes. Experimental studies were carried out to understand the heat transfer behaviours of heat pipes. One heat pipe with the working fluid of HFC-134a was evaluated. The heat pipe is made of aluminium plate and has the width of 50 mm and thickness of 1.9 mm. Numerical and experimental results relevant to the heat transport capability of the heat pipe were analysed and compared.
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Cui, Michael M. "Unsteady Flow Around Suction Elbow and Inlet Guide Vanes in a Centrifugal Compressor." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53273.

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A suction elbow and inlet guide vanes (IGVs) are typical upstream components in the front of the first-stage impeller in a centrifugal compressor. Since the flow field in the front of the impeller is subsonic, the flow motion induced by the rotating impeller interacts with the elbow and IGVs. These interactions induce turbulent unsteady flows inside compressors. The resulted unsteadiness affects efficiency, vibration, and noise generation of the compressor. To understand the mechanism controlling the interactions between up-steam components and to optimize the compressor design for better efficiency and reliability, the turbulent unsteady flow inside the first-stage of the compressor was simulated. The model includes the suction elbow, inlet guide vane housing, and first-stage impeller. HFC 134a was used as the working fluid. The thermodynamic and transport properties of the refrigerant gas were modeled by the Martin-Hou equation of state and power laws, respectively. The three-dimensional unsteady flow field was numerically simulated. The overall performance parameters were obtained by integrating the field quantities. The force, torque, and the arm of moments acting on the IGVs are then calculated. The results can be used to improve centrifugal compressor design to achieve higher efficiency and improve reliability.
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