Design method of plate heat exchanger average temperature difference method

A lot of people don't know how to calculate the average temperature difference of a plate heat exchanger, so here's a little explanation!

1, Calculate the unknown temperature or flow rate, and also the heat load through the heat balance equation.

2, choose the appropriate plate type, according to the size of the heat transfer and flow rate.

The selection of plate type should be based on the specific working conditions. When the flow rate is large and the pressure drop is low, the plate type with small resistance should be used; on the other hand, the plate type with slightly larger resistance coefficient can be used.

3, Estimate the heat transfer area, according to the heat transfer calculation of the approximate heat transfer area.

4, the selection process and the number of channels, the initial selection of cold, hot fluid flow and the number of channels, and thus calculated flow rate.

5, seek the average temperature difference.

6, for convective heat transfer coefficient and total heat transfer coefficient, the first to find out the cold, hot fluid, respectively, convective heat transfer coefficient, so as to calculate the total heat transfer coefficient.

7, calculate the necessary heat transfer area.

8, back to the accounting of heat transfer area.

9, test pressure drop, allow the pressure drop often becomes a plate heat exchanger design constraints. The efficient design is always required to allow enough pressure drop, if no matter how to change the process layout can not coordinate the heat transfer load, flow and If the relationship between the allowable pressure drop and the design is not satisfactory, an inefficient design solution can only be achieved. If a satisfactory design solution is not achieved throughout the design, a change of plate type may be considered.