Heat Exchangers(换热器).ppt

plate?heat exchanger In the 1920s ?spiral plate heat exchanger? At the early 30s plate-fin heat exchanger lamella heat exchanger shell and tube heat exchanger Since the 60s heat pipe exchanger In the middle of the 70s THANKS! LOGO Page ? * LOGO Heat Exchangers Group: 王圣园 王栋亮 梅振飞 李东旭 Heat Exchangers History Types and principle Maintenance Application In the late 30s back Types and principle There are many different types of heat exchangers. According to the principle of action and heat transfer mode, we can be divided into three kinds： direct contact heat exchanger, regenerative heat exchanger and recuperative heat exchanger. 1.Direct contact heat exchanger Principle：Hot and cold fluid direct mixed with each other to transfer heat. It is suitable for occasions where hot and cold fluids can be mixed, such as cold water tower, gas washing tower, spray type heat exchanger and so on. PICTURES 2. Regenerative heat exchanger Principle：It requires a large heat capacity of solid heat storage, which help transfer heat from the hot fluid to cold fluid. When heat accumulator is in contact with the hot fluid, heat accumulator absorbs heat. Then heat accumulator releases heat when it is in contact with cold fluid. It is suitable for high temperature gas recovery and cooling. Such as Rotary air preheater. PICTURES 3. Recuperative heat exchanger Principle：Recuperative heat exchanger refers to two different temperatures of fluid which flow in the fixed wall surface (known as the heat transfer area) separated by space, through wall surface’s heat conduction and convection to transfer heat . It is suitable for the place where hot and cold fluid is not allowed to mix. Such as Shell and tube heat exchanger and Plate heat exchanger. PICTURES BACK Application of the heat exchangers heat exchanger A heat exchanger is a device used to transfer heat between one or more fluids. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contac