Plate heat exchanger design needs to know 5 parameters
Generally speaking, the selection and design of plate heat exchangers need to know 5 parameters:
The thermal power of the plate heat exchanger.
The temperature of the inlet water on the primary side of the plate heat exchanger.
The temperature of the outlet water on the primary side of the plate heat exchanger.
The inlet water temperature on the secondary side of the plate heat exchanger.
The outlet water temperature on the secondary side of the plate heat exchanger.
Knowing these 5 parameters can design. In addition, when designing a plate heat exchanger, you need to know the flow rate on the primary side, which is actually the result of dividing the power of the plate heat exchanger (converted into kcal) by the temperature difference between the inlet and outlet water on the primary side. Let me briefly explain the specific meaning of these 5 parameters.
1. The selection of the flow velocity between the heat exchanger plates is generally 0.2m/s as the lower limit, but the upper limit of 0.8m/s seems to be slightly lower. But it depends on the manufacturer's sheet corrugation.
2. The process is determined. The plate heat exchanger process is generally arranged as a single process in the industry, so that it does not need to be dismantled and taken over during maintenance. In hygiene and food, there are many applications of multiple processes. Because plate heat exchangers are generally relatively small.
3. Selection of the area of single heat exchange plate. Generally, the choice of plate heat exchanger is to determine the diameter of the corner hole according to the flow rate. The flow rate at the corner hole is generally controlled to not exceed 6m/s, and the steam flow rate does not exceed 80m/s. After the size of the plate holes is determined, the series of the heat exchanger plates can be determined.
4. Selection of flow direction, general plate heat exchangers are arranged in pure countercurrent flow.
5. The size of the plate area of a single heat exchanger should be considered in terms of price when the process requirements are met. From the cost ratio of the plate area of a single heat exchanger, the larger the cheaper, but the price of the whole machine must consider the price of the frame, so it should be considered comprehensively. The single chip area is small, the frame price is low, but the board unit price is high. Moreover, the area of a single chip is too small, and in addition to occupying a large area, it is generally difficult to achieve a single-process heat exchanger plate layout.
