(1) The tube plate and the shell of the tube bundle of fixed tube-plate heat exchanger are connected together. The structure is simple, but it is only suitable for the heat transfer operation when the temperature difference between cold and hot fluid is not big and the shell side does not need mechanical cleaning. When the temperature difference is a little large and the pressure on the shell side is not too high, an elastic compensation ring can be installed on the shell to reduce the thermal stress.
(2) The tube plate at one end of the tube bundle of floating head heat exchanger can float freely, which completely eliminates the thermal stress; And the whole tube bundle can be extracted from the shell, convenient for mechanical cleaning and maintenance. Floating head heat exchanger is widely used, but its structure is more complex and its cost is higher.
(3) U type tube heat exchanger each heat exchange tube is bent into a U shape, both ends are respectively fixed in the same tube plate up and down the two areas, with the help of the partition in the tube box is divided into import and export two rooms. This kind of heat exchanger completely eliminates the thermal stress, the structure is simpler than the floating head type, but the tube is not easy to clean.
(4) eddy current hot film heat exchanger eddy current hot film heat exchanger adopts the latest eddy current hot film heat transfer technology, by changing the fluid movement state to increase the heat transfer effect, when the medium through the eddy current tube surface, strong erosion of the tube surface, so as to improve the heat transfer efficiency. Up to 10000W/m2℃. At the same time, the structure realizes the function of corrosion resistance, high temperature resistance, high pressure resistance and anti scaling. The fluid channels of other types of heat exchangers are in the form of fixed direction flow, and the flow around the surface of the heat exchange tube is formed, and the convective heat transfer coefficient is reduced.
