A proton exchange membrane (PEM) fuel cell is an electrochemical device that produces “clean” electricity from a chemical reaction between hydrogen and oxygen with only water and heat as byproducts. Mismanagement of the heat generated in the cells drops performance and jeopardizes reliable and safe operations.In a classic system the coolant controls for a PEM fuel cell stack uses a feedback control that is based on the actual temperature value measured at the outlet of the coolant channel. This is known as a “bang-bang” or proportional-integral (PI) controller.
Shift to coolants and refrigerants with lower GWP
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Objective
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Disclosed herein are refrigerant or heat transfer fluid compositions further comprising fluoroether 111223344-nonafluoro-4-methoxybutane and hydrofluorocarbon which are useful in refrigeration or air conditioning apparatus or as heat transfer fluids. The compositions of the present invention are also useful in centrifugal compressor apparatus that employ two-stage compressors or single slab/single pass heat exchangers.
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BESCON improves the performance of your air-conditioner and promises longer life. Boost up ability of your air-conditioner and save power consumption: easy installation reduction of electricity bill and CO2 best solution to an irregular stop caused by high pressure. With our accumulated knowledge the stable energy conservation has been realized.
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The common problem of building air-conditioning systems such as those in non-residential buildings is the inability to match the system’s cooling capacity to the imposed cooling load. Most often the compressors are set to operate at the maximum speed providing maximum cooling capacity at all time resulting in unnecessary waste of energy. Even the traditional on/off thermostat control is not desirable from the perspective of compressor’s operation and affects the life span of the system. ATCS on the other hand allows the compressors to operate continuously at reduced capacity.
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Objective
The present invention relates to compositions for use in refrigeration and air-conditioning systems comprising 111223344-nonafluoro-4-methoxybutane and at least one chlorocarbon alcohol ether ester N-(difluoromethyl)-NN-dimethylamine or mixtures thereof. Further the present invention relates to compositions for use in refrigeration and air-conditioning systems employing a centrifugal compressor comprising 111223344-nonafluoro-4-methoxybutane and at least one chlorocarbon alcohol ether ester N-(difluoromethyl)-NN-dimethylamine or mixtures thereof.
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111224555-Nonafluoro-4-(Trifluoromethyl)-3-Pentanone Refrigerant Compositions Comprising a Hydrofluorocarbon and Uses Thereof
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A magnetic process comprising: subjecting a magnetically susceptible media to a magnetic field wherein the fluid is magnetized and the magnetized media absorbs the heat of magnetization; transferring the absorbed heat from the magnetized fluid or solid to a heat sink; removing the magnetized magnetic media from the magnetic field wherein the magnetic media undergoes spontaneous cooling to produce a cooled magnetic media; and providing heat to the cooled magnetic media from a heat source and wherein said process is accomplished at above about 275 degrees Kelvin
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Disclosed herein are refrigerant and heat transfer fluid compositions comprising 111224555-nonafluoro-4-(trifluoromethyl)-3-pentanone and at least one hydrofluorocarbon for use in refrigeration and air conditioning systems employing a centrifugal compressor. The compositions may be azeotropic or near-azeotropic.
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Technology
Organic absorption heat pump (AHP) system offers highly efficient performance contributing reduction of CO2 which is an universal proposition. Even the climate tends to warmer consumption of electricity should be saved in order to reduce CO2 exhaust. This Appliance may be used for Heating Cooling and Domestic Hot Water Production developed originally for use in individual house. AHP is an Air-Source or Geothermal-Source Heat Pump driven not by electricity but by natural Gas of minimum volume.
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Research at the University of California Berkeley has led to the development of an innovative approach that addresses the material issues which have traditionally prevented the use of closed gas power cycles with liquid metal and molten salt coolants. Design calculations that apply these innovations have shown that cycle thermal efficiencies comparable to current helium-cooled reactor designs (> 45%) can be achieved using turbomachinery equipment and operating parameters very similar to those for current helium cooled high-temperature gas reactors.