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High Temperature Heat Pump Using Hfo And Hcfo Refrigerants - System Design, Simulation, And First Experimental Results, Cordin Arpagaus, Frédéric Bless, Michael Uhlmann, Elias Büchel, Stefan Frei, Jürg Schiffmann, Stefan Bertsch
High Temperature Heat Pump Using Hfo And Hcfo Refrigerants - System Design, Simulation, And First Experimental Results, Cordin Arpagaus, Frédéric Bless, Michael Uhlmann, Elias Büchel, Stefan Frei, Jürg Schiffmann, Stefan Bertsch
International Refrigeration and Air Conditioning Conference
High temperature heat pumps (HTHPs) with heat sink temperatures in the range of 100 to 160°C are expected to become increasingly commercialized in the coming years. Major applications have been identified, particularly in the food, paper, metal and chemical industries, especially in drying, sterilization, evaporation, and steam generation processes. With the intensification of the F-gas regulations, only refrigerants with low GWP may be used in the near future. Replacement fluids for the currently applied hydrofluorocarbons (HFCs) R245fa and R365mfc are required. The actual research gap in the field of HTHPs is to extend the limits of efficiency and heat sink …
Investigations Of Heat Transfer And Components Efficiencies In Two-Phase Isobutane Injector, Kamil Smierciew, Dariusz Butrymowicz, Mark Bergander, Tomasz Przybylinski
Investigations Of Heat Transfer And Components Efficiencies In Two-Phase Isobutane Injector, Kamil Smierciew, Dariusz Butrymowicz, Mark Bergander, Tomasz Przybylinski
International Refrigeration and Air Conditioning Conference
Renewable energy sources may be applied to drive refrigeration and air-conditioning systems, e.g. solar radiation, geothermal resources, heat derived from biomass or waste heat rejected form various thermal processes. In this case absorption refrigeration systems and ejection systems may be used for cooling applications. In both these systems the crucial problem is the development of a suitable liquid pump. Energy consumption to drive these systems is not a major problem here as in most cases amount of energy required to drive a mechanical pump is a contribution of at most a few percent of the overall energy balance of the …
New Lubricants To Enable Performance, Efficiency, And Reliability, Julie Ann Majurin, Anthony Barthel
New Lubricants To Enable Performance, Efficiency, And Reliability, Julie Ann Majurin, Anthony Barthel
International Refrigeration and Air Conditioning Conference
This paper will highlight case studies of physical and chemical interactions between refrigerants, lubricants, and components in HVACR systems from recent evaluations of new low GWP refrigerants, and will emphasize the value of including lubricants as an integral component of technology and product development roadmaps. Refrigerant/lubricant mixture properties, such as miscibility, solubility, and viscosity, are critical to understand to meet design, operation, and reliability goals of HVACR equipment. In this paper, we will discuss miscibility and solubility challenges of specific new refrigerants, and review how these challenges have been addressed using advanced capabilities and deep understanding. Working viscosity is one …
Flashing Liquid Expander Energy Reduction In Refrigeration Systems, Lance Hays
Flashing Liquid Expander Energy Reduction In Refrigeration Systems, Lance Hays
International Refrigeration and Air Conditioning Conference
Expansion valves in refrigeration systems can be replaced with a flashing liquid expander (FLE) to reduce the energy consumption in refrigeration systems. The original application, pioneered by J.J. Brasz, was for commercial 500 Ton chillers. A reduction in compressor power of 7-8% was obtained. Some 100 of these chillers have been operating for more than 10 years. Recent emphasis on the use of environmentally benign refrigerants have created a renewed interest in energy savings. Some refrigerents such as ammonia, carbon dioxide and propane have high lifts resulting in increased inefficiency due to the isenthalpic expansion valve. Useful power is disipated …
A Low Emission, Electrified Solution For Refrigerated Trucking, Shawn Wilfred Vehr
A Low Emission, Electrified Solution For Refrigerated Trucking, Shawn Wilfred Vehr
International Refrigeration and Air Conditioning Conference
Multiple Factors Are Driving Commercial Trucking Toward Electrified Solutions Which Will Lower Harmful Greenhouse Gas Emissions, Improve Efficiency And Reduce Fuel Consumption. As Part Of This, The Refrigerated Trucking Industry Is Searching For Methods To Meet These New Requirements. Today Most Refrigerated Truck Solutions Use A Diesel Engine To Provide Power For The Refrigeration System. This Diesel Engine Is A Source Of Pollutants Which Are Beginning To Be Federally Regulated By The EPA And State Regulated By Groups Such As The California Air Resource Board (CARB). In Addition, This Diesel Engine Is A Source Of Noise And Excessive Fuel Consumption. …
Free Subcooling With The Sky: Improving The Efficiency Of Air Conditioning Systems, Eli A. Goldstein, Dennis Nasuta, Song Li, Cara Martin, Aaswath Raman
Free Subcooling With The Sky: Improving The Efficiency Of Air Conditioning Systems, Eli A. Goldstein, Dennis Nasuta, Song Li, Cara Martin, Aaswath Raman
International Refrigeration and Air Conditioning Conference
Radiative sky cooling is a passive process that can be harnessed to subcool refrigerants in air conditioning and refrigeration systems, thereby increasing the cooling capacity of the refrigerant, and improving the underlying efficiency of the base cooling system. Here, we demonstrate for the first time the use of a radiative sky cooling-enabled passive fluid cooling panel to improve the efficiency of an air conditioning system by subcooling. The panel’s passive cooling capability is enabled by a multilayer optical film that enables the sky cooling effect 24-hours a day. The film is simultaneously a good reflector of solar energy and a …
Application Of Optimization Of Compressors Used In Air Conditioning Units, Joel Vinod Aralikatti, David Zietlow
Application Of Optimization Of Compressors Used In Air Conditioning Units, Joel Vinod Aralikatti, David Zietlow
International Refrigeration and Air Conditioning Conference
Total life-cycle cost of a system are the costs incurred by the owner over the entire life of the system. The two main components of this are: 1) initial cost: cost to purchase the system, often defined by the total/maximum capacity and quality of the system, and 2) operating cost: the cost of operation over the entire life of the system, defined by the daily usage and the efficiencies of the system and its components. Most compressors are designed by trying to minimize the initial cost. Minimal data are available on the selection of a compressor based on its design …
Model-Based Performance Comparison Of Ammonia Chemisorption Heat Pumps For Cold Climate With Different Working Pairs And Cycle Configurations, Zhiyao Yang, Ming Qu, Kyle Gluesenkamp
Model-Based Performance Comparison Of Ammonia Chemisorption Heat Pumps For Cold Climate With Different Working Pairs And Cycle Configurations, Zhiyao Yang, Ming Qu, Kyle Gluesenkamp
International Refrigeration and Air Conditioning Conference
Sorption heat pumps utilize the thermal effect of the sorbent bonding with the refrigerant (sorbate) through a variety of physio-chemical processes, and when such bonding is due to chemical reaction between solid sorbent and gas refrigerant, the system is known as chemisorption heat pump. The most commonly used refrigerant in chemisorption systems is ammonia, and it can work with a variety of sorbent materials across a wide temperature range. The abundance in working pair selection and the viability of resorption configuration leads to multiple available cycle configurations and working pairs for heat pump system design. Therefore, preliminary evaluation of these …