Cooling water

Water cooling is a method of heat removal from components and industrial equipment. As opposed to air cooling, water is used as the heat conductor. Water cooling is commonly used for cooling automobile internal combustion engines and large industrial facilities such as steam electric power plants, hydroelectric generators, petroleum refineries and chemical plants. Other uses include cooling the barrels of machine guns, cooling of lubricant oil in pumps; for cooling purposes in heat exchangers; cooling products from tanks or columns, and recently, cooling of various major components inside high-end personal computers. The main mechanism for water cooling is convective heat transfer.

Cooling water is the water removing heat from a machine or system. Cooling water may be recycled through a recirculating system or used in a single pass once-through cooling (OTC) system. Recirculating systems may be open if they rely upon cooling towers or cooling ponds to remove heat or closed if heat removal is accomplished with negligible evaporative loss of cooling water. A heat exchanger or condenser may separate non-contact cooling water from a fluid being cooled, or contact cooling water may directly impinge on items like saw blades where phase difference allows easy separation. Environmental regulations emphasize the reduced concentrations of waste products in non-contact cooling water.

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