Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Purdue University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 11311 - 11340 of 50131

Full-Text Articles in Entire DC Network

Improving The Reliability Of A Domestic Refrigerator Compressor Subjected To Repetitive Loading, Seongwoo Woo, Dennis O'Neal Jan 2018

Improving The Reliability Of A Domestic Refrigerator Compressor Subjected To Repetitive Loading, Seongwoo Woo, Dennis O'Neal

International Compressor Engineering Conference

As a reliability quantitative specification, parametric accelerated life testing was used to assess the reliability of a newly designed compressor of a commercial refrigerator subjected to repetitive stresses. A generalized life-stress failure model and new sample size equation with a new load concept were derived starting with the basic refrigeration cycle. The sample size equation with the acceleration factor also enabled the parametric accelerated life testing to quickly evaluate the expected lifetime. The design of this testing should help an engineer uncover the design parameters affecting reliability during the design process of the compressor system. Consequently, it should help companies …

Go to article

Development And Practical Application Of A Natural Gas Expansion Turbine For Power Generation Without Additional Heating Equipment, Hanushan Vasuthevan, Andreas Bruemmer, Christian Badura Jan 2018

Development And Practical Application Of A Natural Gas Expansion Turbine For Power Generation Without Additional Heating Equipment, Hanushan Vasuthevan, Andreas Bruemmer, Christian Badura

International Compressor Engineering Conference

The efficient transportation of natural gas takes place with high pressure before it is distributed to the consumer with a lower pressure. Generally, pressure reduction in gas grids is realized in pressure control stations with a regulating valve, where the dissipative energy remains as heat in the fluid. Nevertheless, the temperature of natural gas decreases during the pressure reduction due to the Joule-Thomson-Effect, depending on pressure difference of the regulating valve. For higher pressure differences it is necessary to preheat the natural gas to prevent condensate formation and freezing of pipelines. Instead of using a regulating valve, an expansion machine …

Go to article

Thermodynamic Modelling Of Reciprocating And Wankel Type Compressor For Household Refrigerators, Konrad Klotsche, Thomas W. Moesch, Gotthard Will, Ullrich Hesse Jan 2018

Thermodynamic Modelling Of Reciprocating And Wankel Type Compressor For Household Refrigerators, Konrad Klotsche, Thomas W. Moesch, Gotthard Will, Ullrich Hesse

International Compressor Engineering Conference

Recent studies point out various benefits of trochoid-type compressors in vapor compression heat pump cycles and air compression applications. However, the field of small household refrigeration is still dominated by reciprocating compressors. This study comparatively investigates the thermodynamic behavior of a reciprocating and Wankel-type compressor in household refrigerators using the compressor simulation software KVA, which has been developed at the TU Dresden. The results of the KVA calculations are compared to available experimental data of a typical household refrigeration compressor. The comparative investigation reveals the differences between both compressor types regarding internal losses such as flow losses and internal leakages …

Go to article

Development Of Miscibility Improved Oil For R32, Yuya Mizutani, Takeshi Okido, Yohei Shono, Kiyomi Sakamoto Jan 2018

Development Of Miscibility Improved Oil For R32, Yuya Mizutani, Takeshi Okido, Yohei Shono, Kiyomi Sakamoto

International Compressor Engineering Conference

R32 has been widely applied as an air-conditioner refrigerant. It is known that R32 is inferior to other refrigerants such as HFC and HFO in the miscibility with refrigeration oils. In addition, when R32　dissolves in refrigeration oils, the kinematic viscosity of the oils reduces remarkably. So it is difficult to improve the miscibility of refrigeration oil while suppressing the kinematic viscosity decrease of the oil when R32 dissolves in. Various investigations have revealed that the formulation of a new base material in POE improves the miscibility with R32 without decreasing the kinematic viscosity of the oil when R32 dissolves …

Go to article

Influence Of Wear On Leakage Through Reed-Type Valves Of Small Reciprocating Compressors, Fernanda L. Dos Santos, Ernane Silva, Cesar J. Deschamps Jan 2018

Influence Of Wear On Leakage Through Reed-Type Valves Of Small Reciprocating Compressors, Fernanda L. Dos Santos, Ernane Silva, Cesar J. Deschamps

International Compressor Engineering Conference

Leakage can significantly decrease the efficiency of small reciprocating compressors adopted in household refrigeration systems. Leakage occurs in the piston-cylinder clearance and through gaps in valves formed by geometric irregularities associated with the manufacturing process. This paper presents a procedure developed to analyze experimentally gas leakage in reed-type valves taking into account the wear effect. Accordingly, leakage is measured in the valves of a small-capacity reciprocating compressor before and after the valves being subjected to wear, with the roughness of the reed and seat being measured in both conditions. Measurements of leakages in the suction and discharge valves were carried …

Go to article

A Numerical Study On The Temperature Field Of A R290 Hermetic Reciprocating Compressor With Experimental Validation, Rui Wu, Bei Guo, Jinliang Tuo, Yu Zhang, Xiaole Chen, Ruixin Zhou Jan 2018

A Numerical Study On The Temperature Field Of A R290 Hermetic Reciprocating Compressor With Experimental Validation, Rui Wu, Bei Guo, Jinliang Tuo, Yu Zhang, Xiaole Chen, Ruixin Zhou

International Compressor Engineering Conference

A numerical model to predict the temperature field in a R290 hermetic reciprocating compressor is presented in this work. The control volume method and the lumped parameter method are used in the simulation. The compressor is divided into 6 control volumes, including the suction muffler, the cylinder, the discharge chamber, the discharge muffler, the discharge pipe and the shell. The system of non-linear equations is formed of the energy balance equations of every control column. The temperature field is derived by solving the equations. To valid the numerical model accurately, temperature experiment has been carried out in 3 same-type hermetic …

Go to article

Scroll Wrap Additional Stress In Variable Speed Application, Dominique Gross, David Genevois Jan 2018

Scroll Wrap Additional Stress In Variable Speed Application, Dominique Gross, David Genevois

International Compressor Engineering Conference

The HVAC industry reaches a whole new level in terms of efficiency, comfort, reliability, and versatility by using Danfoss variable speed compressor technology. Variable speed systems work by connecting a motor control drive to a compressor, such as Recip (VTZ), Scroll (VRJ, VSH, VZH), or Centrifugal (TT, VTT, TG). Especially in terms of Scroll technology, Danfoss Commercial Compressors consistently performs detailed studies on the wrap stresses. Understanding the mechanical behavior of compressor wraps (as the compressor runs), is one of the most important criteria that has to be considered in the design process to guarantee a high reliability. Wraps are …

Go to article

Miniature Oil-Less Linear Compressor For Portable Oxygen Concentrator, Hyeongkook Lee, Haoyi Sun, Yeongheon Kim Jan 2018

Miniature Oil-Less Linear Compressor For Portable Oxygen Concentrator, Hyeongkook Lee, Haoyi Sun, Yeongheon Kim

International Compressor Engineering Conference

There are many handicapped people who need portable oxygen concentrator which operated by battery power. The weight and period of use of this product critically limit the activity range of those handicapped people. The oil-less air compressor inside of it is very critical because this compressor is the biggest power consuming part in this product. We developed miniature oil-less linear compressor with internal dynamic vibration absorber. Energy efficiency is improved by 28~38% compared with the conventional rocking piston type reciprocating compressor currently used for such products. PTFE coating for the piston and Diamond Like Carbon (DLC) coating for the cylinder …

Go to article

Identification Of The Generalized Transfer Matrix For The Nozzle-Type Element. Comparison Of The Cfd-Based And Analytical Methods., Przemyslaw Mlynarczyk Jan 2018

Identification Of The Generalized Transfer Matrix For The Nozzle-Type Element. Comparison Of The Cfd-Based And Analytical Methods., Przemyslaw Mlynarczyk

International Compressor Engineering Conference

Pressure pulsations caused by a volumetric machines are still an important problem in the compressors, pumps and diesel engines manifolds and pipelines operation. Nowadays the problem is much more significant, for example, in the refrigeration industry where the variable revolution speed compressors are widely introduced. The classical Helmholtz resonators can attenuate the pulsations only in a narrow range of frequencies. One of the possibility to attenuate the pressure pulsations is to introduce the shaped nozzles into the compressor outflow and inflow pipelines. It Is a problem to introduce transfer matrix of the nozzle with variable geometry to the classical Helmholtz …

Go to article

Flow Visualization And Analytical Model Of Coalescing Oil Separator For Compressors, Jiu Xu, Predrag S. Hrnjak Jan 2018

Flow Visualization And Analytical Model Of Coalescing Oil Separator For Compressors, Jiu Xu, Predrag S. Hrnjak

International Compressor Engineering Conference

Oil management is an important issue for compressors. Oil circulating in the vapor compression system is harmful for the heat exchanger performance and the compressor reliability. Therefore, oil separation is commonly needed in air conditioning or refrigeration systems to reduce the oil circulation ratio and return the oil back to the compressor. For compactness, oil separation structure integrated into the compressor is more and more popular than traditional external oil separator. However, a quantitative guideline for oil separation structure design is missing for irregular geometry and realistic flow condition at the compressor discharge. In this paper, coalescence, as one of …

Go to article

An Experimental-Numerical Procedure To Characterize Compressor Performance Under Cycling Operating Conditions Of Refrigerators, Daniel Faitao Balvedi, Marco C. Diniz, Cesar J. Deschamps Jan 2018

An Experimental-Numerical Procedure To Characterize Compressor Performance Under Cycling Operating Conditions Of Refrigerators, Daniel Faitao Balvedi, Marco C. Diniz, Cesar J. Deschamps

International Compressor Engineering Conference

The design of reciprocating compressors is commonly based on steady-state operating conditions. However, most household refrigerators operate under transient and periodic regimes, characterized by alternate periods in which the compressor is either operating (on) or not operating (off). The result is a decoupled design approach since stabilized conditions not necessarily represent the actual operating conditions of refrigerators. This paper presents a strategy in which a virtual refrigeration system is developed and coupled to an experimental facility in order to test compressors under on-off conditions typical of household refrigerators. The virtual refrigeration system simulates the dynamic behavior of a household refrigerator, …

Go to article

A Study On Novel High Efficiency Vane Compressor, Yusheng Hu, Jia Xu, Pengkai Wan, Fayou Luo, Fei Wu, Liping Ren Jan 2018

A Study On Novel High Efficiency Vane Compressor, Yusheng Hu, Jia Xu, Pengkai Wan, Fayou Luo, Fei Wu, Liping Ren

International Compressor Engineering Conference

This paper proposed a novel high efficiency structure of vane compressor. This kind of compressor can translate the sliding friction between the vane and cylinder into the rolling friction, which can significantly reduce the loss of mechanical friction. Comprared with the conventional vane compressor, this has been proved high efficiency and high reliability. Then the structure and operation principle was introduced; differences of mechanical friction loss between the two compressors were comprared and analyzed in this paper.

Go to article

Development Of A Light-Commercial Compressor Load Stand To Measure Compressor Performance Using Low-Gwp Refrigerants, Drew Schmidt, Jake Singleton, Craig Bradshaw Jan 2018

Development Of A Light-Commercial Compressor Load Stand To Measure Compressor Performance Using Low-Gwp Refrigerants, Drew Schmidt, Jake Singleton, Craig Bradshaw

International Compressor Engineering Conference

Popular hydrofluorocarbon refrigerants such as R134a and R410A are in the process of being phased out due to the high Global Warming Potential (GWP) of these fluids. A large variety of low-GWP refrigerants are being considered as replacements including R1234yf, R1234ze(E), R1234ze(D), R32, and blends of these with traditional refrigerants. As a result of high efficiency standards for HVAC&R equipment, the choice of refrigerant has a large impact on the design of a compressor to maximize its efficiency. Therefore, changing the most common refrigerants will require significant design changes to compressors and test environments that support re-design activities such as …

Go to article

Comparison And Evaluation Of Different A/C Compressor Concepts For Electric Vehicles, Joerg Aurich, Rico Baumgart Jan 2018

Comparison And Evaluation Of Different A/C Compressor Concepts For Electric Vehicles, Joerg Aurich, Rico Baumgart

International Compressor Engineering Conference

With the development of electric cars the cooling and heating of the passenger compartment is even today a major challenge for the automotive industry. Apart from the passenger compartment, the A/C system in today’s electric vehicles cools and heats auxiliary devices like the battery and the power electronics. The high demand of heating and cooling power leads to a significant reduction in cruising range. In the A/C systems of electric vehicles, electric driven scroll compressors are widely used. These compressors have several advantages compared with axial piston compressors used in conventional cars, e.g. easy controllability as well as good efficiencies …

Go to article

Compressor Friction Losses Due To Oil Viscosity And Asperity Contact Surfaces: A Numerical Study On Crankshaft Bearings Lengths, Clearances And Roughness Parameters, Anderson Moises Meier, Mauricio Pereira Tada, Guilherme Espindola Jan 2018

Compressor Friction Losses Due To Oil Viscosity And Asperity Contact Surfaces: A Numerical Study On Crankshaft Bearings Lengths, Clearances And Roughness Parameters, Anderson Moises Meier, Mauricio Pereira Tada, Guilherme Espindola

International Compressor Engineering Conference

High energy efficiency refrigeration compressors have been increasingly demanded. This is achievable not only by the use of an efficient thermodynamic system and an efficient electric motor, but also by the design technologies applied to the compressor mechanism. In this work, a crankshaft bearing power losses optimization is presented regarding journal/shell surfaces run-in. The crankshaft bearings asperity friction power losses, combined with the viscous friction power losses, has been minimized for a reciprocating compressor running at ASHRAE condition. The core of the present approach was exploring a design space – computing asperity friction and viscous friction power losses – regarding …

Go to article

Numerical And Experimental Research On Vibration Mechanism Of Rotary Compressor, Zhiqiang Deng, Chaolei Zhang, Xiaoqiang Huang, Yong Wang, Haishui Jin Jan 2018

Numerical And Experimental Research On Vibration Mechanism Of Rotary Compressor, Zhiqiang Deng, Chaolei Zhang, Xiaoqiang Huang, Yong Wang, Haishui Jin

International Compressor Engineering Conference

With a typical rotary compressor as the research object, the vibration mechanism of the rotary compressor was analyzed in detail in this work. And according to the work, the formulations of the tangential vibration and the radial vibration were proposed for the rotary compressor. First, the oil film stiffness and the damp coefficient were obtained by coupling the experimental testing method and numerical simulation. Then a dynamics simulation was conducted for the rotor system and the critical speed for the current rotor system was obtained, which was used to judge if the rotor system is a kind of flexible rotor. …

Go to article

Stress Analysis Of Key Components And Vibration Property Research Of The Meshing Pair In Single Screw Compressors, Chengyu Peng, Zhao Zhang, Pankang Xiong, Lei Liu, Quanke Feng, Weifeng Wu Jan 2018

Stress Analysis Of Key Components And Vibration Property Research Of The Meshing Pair In Single Screw Compressors, Chengyu Peng, Zhao Zhang, Pankang Xiong, Lei Liu, Quanke Feng, Weifeng Wu

International Compressor Engineering Conference

The single screw compressor(SSC) is widely applied to air compression, refrigeration, petrochemical industry, waste heat recovery, etc. Among SSCs, the respective strength and stiffness of the casing, screw rotor and gaterotor, where relative motions occur, play a key role on the machine running and clearance fit. Dynamic properties of the meshing pair directly affect the SSC’s vibration, as well as gaterotor’s wear-out failure. In this thesis, the strength, stiffness and dynamic characteristics of the meshing pair under different operation conditions or with components made of different materials were analyzed. Analytical method and FEM were combined to calculate and analyze the …

Go to article

Experimental Investigation On R245fa Throttling Devices Under High Temperature, Mingyue Huang, Xiangfei Liang, Yingwen Wu, Bo Zheng, Youlin Zhang Jan 2018

Experimental Investigation On R245fa Throttling Devices Under High Temperature, Mingyue Huang, Xiangfei Liang, Yingwen Wu, Bo Zheng, Youlin Zhang

International Refrigeration and Air Conditioning Conference

The experiments on mass flow rate characteristics of R245fa refrigerant flowing through throttling devices including seven capillary tubes and the electronic expansion valve were carried out under the high-temperature working conditions. By combining data analysis with flow correlations, the design basis that is applicable to R245fa throttling devices can be obtained. By comparing the experimental mass flow rate with that predicted by Jung Correlation and Kim Correlation, it can be concluded that root mean square deviations of two correlations are 3.2 % and 3.3%, respectively. The root mean square deviation for electronic expansion valve is 4.5%. The conclusions offer high-accuracy …

Go to article

A Review Of Recent Advances In Additively Manufactured Heat Exchangers, Ellery Klein, Jiazhen Ling, Vikrant Chandramohan Aute, Yunho Hwang, Reinhard Radermacher Jan 2018

A Review Of Recent Advances In Additively Manufactured Heat Exchangers, Ellery Klein, Jiazhen Ling, Vikrant Chandramohan Aute, Yunho Hwang, Reinhard Radermacher

International Refrigeration and Air Conditioning Conference

Heat exchangers are a recurrent element found in an abundant number of mechanical engineering systems. The design of these heat exchangers has generally remained static due to manufacturing limitations. However, recently additive manufacturing has facilitated the production of new and previously impossible heat exchanger geometries and structures by fabricating one monolithic build layer-by-layer. For example, Direct Metal Laser Sintering (DMLS) creates approximately 20-micron thick metal layers stacked on top of one another to create a cohesive metal part. Heat exchangers can be constructed in the same way. Improvements of an additively manufactured heat exchanger include using less material, reduced volume, …

Go to article

R1233zd(E) And R245fa Flow Boiling Heat Transfer And Pressure Drop Inside A 4.2 Mm Id Microfin Tube, Giovanni A. Longo, Andrea Diani, Giulia Righetti, Claudio Zilio Jan 2018

R1233zd(E) And R245fa Flow Boiling Heat Transfer And Pressure Drop Inside A 4.2 Mm Id Microfin Tube, Giovanni A. Longo, Andrea Diani, Giulia Righetti, Claudio Zilio

International Refrigeration and Air Conditioning Conference

This paper presents R1233d(E) and R245fa flow boiling heat transfer and pressure drop measurements inside a mini microfin tube having internal diameter at the fin tip equal to 4.2 mm, 40 fins 0.15 mm high, and a helix angle of 18°. The tube was brazed inside a copper plate and electrically heated from the bottom. Sixteen T-type thermocouples were located in the copper plate to monitor the wall temperature. The experimental measurements were carried out at a constant mean saturation temperature of 30 °C, by varying the refrigerant mass velocity between 100 kg m-2 s-1 and 300 kg m-2 s-1, …

Go to article

Numerical Modeling Of Fin-And-Tube Condenser With Wet-Wall Desuperheating, Hongtao Qiao, Christopher Laughman Jan 2018

Numerical Modeling Of Fin-And-Tube Condenser With Wet-Wall Desuperheating, Hongtao Qiao, Christopher Laughman

International Refrigeration and Air Conditioning Conference

Current heat exchanger simulation models typically divide the condenser into three regimes (desuperheating, two-phase and subcooled) and assume that condensation does not start until the bulk refrigerant flow reaches a state of saturated vapor. However, plenty of experiments have verified that condensation can occur much earlier than that when the tube wall surface temperature drops below the dew point of refrigerant even though the bulk flow is still superheated. This phenomenon is called wet-wall desuperheating (also referred to as wet-desuperheating, or condensation from desuperheated vapor in some publications). Wet-wall desuperheating is rarely modelled in the extant heat exchanger simulations due …

Go to article

Experimental Evaluation Of R410a, R407c And R134a Alternative Refrigerants In Residential Heat Pumps, Pierre Pardo, Michèle Mondot Jan 2018

Experimental Evaluation Of R410a, R407c And R134a Alternative Refrigerants In Residential Heat Pumps, Pierre Pardo, Michèle Mondot

International Refrigeration and Air Conditioning Conference

Protocols and regulations such as the Montreal Protocol (1987), the Kyoto Protocol (1997), the European F-gas regulation (2006) and now its revision (2014) cause a shift toward refrigerants with both zero Ozone Depletion Potential (ODP) and low Global Warming Potential (GWP). Alternative refrigerants with low-GWP are under investigation for residential heat pumps, air-conditioners and heat pump water heaters as R410A, R407C and R134a have GWP of 2088, 1650 and 1430, respectively. In this study, five alternative refrigerants: R459A, R454B, R447A, HPR2A and R32, with GWP of 460, 466, 583, 600 and 675, respectively, were investigated for the replacement of R410A …

Go to article

Geometric Effects Of Horizontal Branching T-Junction On Phase Separation Of Refrigerant, Wen Su, Yunho Hwang, Li Zhao Jan 2018

Geometric Effects Of Horizontal Branching T-Junction On Phase Separation Of Refrigerant, Wen Su, Yunho Hwang, Li Zhao

International Refrigeration and Air Conditioning Conference

Separation technology has been widely developed to improve the performance of thermodynamic cycles, such as refrigeration, heat pump and power cycle. As a promising separator, T-junction has attracted widespread attention, due to the characteristics of simple geometry, low cost and compact size. Previous researches on the phase separation of air-water and steam-water have indicated that the separation performance depends heavily on the T-junction geometry. Therefore, in this work, geometric effects on phase separation of refrigerant were experimentally studied with different configurations of branching T-junction. In this study, all of the T-junctions had horizontal inlet and outlet tubes. The internal diameter …

Go to article

Modeling Of S-Ram Energy Recover Compressor Integration In A Transcritical Carbon Dioxide Cycle For Application In Electronics Cooling In Varying Gravity, Riley Barta, Jason J. Hugenroth, Eckhard A. Groll Jan 2018

Modeling Of S-Ram Energy Recover Compressor Integration In A Transcritical Carbon Dioxide Cycle For Application In Electronics Cooling In Varying Gravity, Riley Barta, Jason J. Hugenroth, Eckhard A. Groll

International Refrigeration and Air Conditioning Conference

As electronics in military aircraft become increasingly complicated, additional cooling is necessary to enable efficient and high computing performance. Additionally, the varying forces that a military aircraft endure during maneuvering and inverted flight introduce unique design constraints to the electronics cooling systems. Because this cooling system will be in an aircraft, the capacity and unique design constraints must all be met with a design that is as lightweight as possible. This paper presents a study comparing the coefficient of performance (COP) of several cycle architectures with both R134a and carbon dioxide ( ). Cycles with single-stage and two-stage compression with …

Go to article

Film Rupture And Partial Wetting Over Flat Surfaces, Niccolo Giannetti, Piyatida Trinuruk, Seiichi Yamaguchi, Kiyoshi Saito Jan 2018

Film Rupture And Partial Wetting Over Flat Surfaces, Niccolo Giannetti, Piyatida Trinuruk, Seiichi Yamaguchi, Kiyoshi Saito

International Refrigeration and Air Conditioning Conference

Various technical applications require conditions which prevent thin liquid films from breaking into a series of rivulets, leaving the solid surface partly uncovered and lowering the extension of the liquid free interface. What is needed is both a criterion for the stability of the film to identify the minimum flow rate able to ensure the complete wetting of the surface and, after the film rupture, a method to estimate the wet (active) part of the same surface. At low Reynolds and high Weber numbers, the assumptions of a film with uniform thickness and complete wetting of the transfer surface cannot …

Go to article

Boiling Heat Transfer And Pressure Drop Of R1234ze(E) Inside A Small-Diameter 2.5 Mm Microfin Tube, Daisuke Jige, Shota Iizuka, Norihiro Inoue Jan 2018

Boiling Heat Transfer And Pressure Drop Of R1234ze(E) Inside A Small-Diameter 2.5 Mm Microfin Tube, Daisuke Jige, Shota Iizuka, Norihiro Inoue

International Refrigeration and Air Conditioning Conference

Currently, the development of high-performance and compact heat exchangers with small- diameter tubes having a hydraulic diameter of less than 5 mm is needed in order to improve the performance of the heat exchanger and to reduce the refrigerant charge for air-conditioning systems. The effects of surface tension and shear stress on boiling heat transfer and flow characteristics become dominant as the tube diameter decreases. In addition, these effects are different from those in conventional-diameter tubes. It is necessary to clarify boiling heat transfer and pressure drop to facilitate the design of evaporators. Furthermore, low global warming potential refrigerants such …

Go to article

Combined Power, Cooling And Desalination Using Natural Refrigerant Powered By Low-Grade Heat Source, Praveen Kumar Govindasamy, Saravanan R, Alberto Coronas, Patrick E. Phelan Jan 2018

Combined Power, Cooling And Desalination Using Natural Refrigerant Powered By Low-Grade Heat Source, Praveen Kumar Govindasamy, Saravanan R, Alberto Coronas, Patrick E. Phelan

International Refrigeration and Air Conditioning Conference

Contemporary facilities experience growing demand of energy-intensive products like cooling, power and fresh water, which turn in results in energy and environmental concerns. The separate production of these intensive products potentially consumes more primary energy compared with combined production (polygeneration). We therefore seek the most sustainable and suitable polygeneration technology. The driving energy source for the polygeneration system is assumed to be low-grade heat available from solar thermal, geothermal, industrial waste heat, etc. The natural refrigerant based ammonia-water absorption system has the potential for more exploration in the field of polygeneration. In the past decades, ammonia-water based Combined Cooling and …

Go to article

Extremum Seeking Control For An Air-Source Heat Pump Water Heating System With Flash Tank Cycle Based Vapor Injection, Wenyi Wang, Yaoyu Li Jan 2018

Extremum Seeking Control For An Air-Source Heat Pump Water Heating System With Flash Tank Cycle Based Vapor Injection, Wenyi Wang, Yaoyu Li

International Refrigeration and Air Conditioning Conference

Vapor injection (VI) techniques have been well received as an effective technology for improving the performance of air-source heat pump (ASHP) under very low ambient temperature, for which the flash tank cycle (FTC) and the internal heat exchanger cycle (IHXC) are the two majaor configurations. In principle, FTC has higher achievable performance than IHXC because that the saturated vapor from the flash tank has a lower temperature which helps reduce the compressor discharge temperature and thus power consumption [1]. However, development of the FTC technology has been hampered by the lack of proper control/operational strategy that can optimize the thermodynamic …

Go to article

Experimental Study On A Finned-Tube Internally Cooled Contactor For Liquid Desiccant Air Conditioning Systems With Ionic Liquid, Takahiro Sato, Richard Jayson Varela, Seiichi Yamaguchi, Kiyoshi Saito, Hiroshi Nakayama, Xinming Wang Jan 2018

Experimental Study On A Finned-Tube Internally Cooled Contactor For Liquid Desiccant Air Conditioning Systems With Ionic Liquid, Takahiro Sato, Richard Jayson Varela, Seiichi Yamaguchi, Kiyoshi Saito, Hiroshi Nakayama, Xinming Wang

International Refrigeration and Air Conditioning Conference

This paper presents an experimental study on the dehumidification performance of a finned-tube internally cooled contactor as compared to that of an adiabatic contactor in liquid desiccant air conditioning systems with ionic liquid. The contactor is the most significant component in liquid desiccant systems; it is the component responsible for the dehumidification and regeneration processes. When air and absorptive solution are in contact in the contactor, absorption/desorption of the solution occurs due to the difference in vapor pressure. This results to the transfer of heat and mass between the air and solution. Conventionally, adiabatic contactors, which only have air and …

Go to article

Experimental Study On Effects Of Lubricant Oil In A Domestic Refrigerator-Freezer, Yunhyuk Choi, Byung-Chae Min, Hyun Kim, G.M. Choi Jan 2018

Experimental Study On Effects Of Lubricant Oil In A Domestic Refrigerator-Freezer, Yunhyuk Choi, Byung-Chae Min, Hyun Kim, G.M. Choi

International Refrigeration and Air Conditioning Conference

Lubricant oil is essential for lubricating moving parts and cooling the components in a refrigerant compressor. However, the oil deteriorates heat transfer performance in the heat exchangers, and increases pressure drop in a refrigeration circuit. In this study, investigation of the effects of lubricant oil circulating in heat exchangers on the performance of the domestic refrigerator-freezer was carried out by performing some experiments. The experiments were conducted for conventional and oil-less systems with using a linear compressor in an environmental chamber to compare the cooling capacity, power consumption, and operating characteristics such as temperatures and pressures at inlets and outlets …

Go to article

First Prev Next Last