The design calculation of plate heat exchanger is the core of plate heat exchanger engineering design, including heat transfer calculation and pressure drop calculation.The engineering design calculation of the plate heat exchanger is different from the traditional shell-and-tube heat exchanger. It does not require any component or structural design. Plate heat exchangers generally do not exceed the maximum operating pressure and are not checked for strength during design.All that is required is to correctly combine the plates and perform heat transfer calculations and pressure drop calculations to obtain the total heat exchange area and number of plates required.Since the heat transfer of the plates is closely related to the pressure drop performance, the calculations in these two aspects often need to be crossed or alternated. In general, the flow rate of the two sides of the fluid and any three of the four inlet and outlet temperatures have been given. The design of the plate heat exchanger should include determining the plate type, the plate size, the combination of the flow and the number of channels, and the heat transfer. area.