Design method of plate heat exchanger average temperature difference method
Heat exchanger plate 1. Calculate the unknown temperature or flow rate, calculate the unknown temperature or flow rate through the heat balance equation, and also calculate the heat load Q.
2. Select the appropriate plate type, and select the appropriate plate type according to the heat exchange amount and flow rate.
The choice of plate model depends on the specific working conditions. When the flow is large and the pressure drop is low, the plate type with low resistance should be selected; otherwise, the plate type with slightly larger resistance coefficient can be used.
3. Estimate the heat exchange area and calculate the approximate heat exchange area based on the heat exchange amount.
4. Select the flow and the number of channels, initially select the cold and hot fluid flow and the number of channels, and calculate the flow rate from this.
5. Find the average temperature difference.
6. To find the convective heat transfer coefficient and the total heat transfer coefficient, first calculate the convective heat transfer coefficients of the cold and hot fluids respectively, so as to calculate the total heat transfer coefficient