Compression systems employ four elements in the refrigeration cycle: compressor, condenser, expansion valve, and evaporator. In the evaporator the refrigerant is vaporized and heat is absorbed from the material contents or the space being cooled. The vapor next is drawn into a motor-driven compressor and elevated to high pressure, which raises its temperature. The resulting superheated, high-pressure gas is then condensed to liquid in an air- or water-cooled condenser. From the condenser the liquid flows through an expansion valve, in which its pressure and temperature are reduced to the conditions that are maintained in the evaporator.
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A stamp depicting the image of Hanaoka Seishu. Hanaoka Seishu (1760-1835), Japanese physician and pioneer of anesthetic surgery. Hanaok... -
In the N and W United States the era of mechanized agriculture began with the invention of such farm machines as the reaper, the cultivator,...
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Fluid Mechanics, physical science dealing with the action of fluids at rest or in motion, and with applications and devices in engineering u...