Plate heat exchanger
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What is the typical allowable pressure drop when the medium in a plate heat exchanger is gas? What is the allowable flow rate? Please explain in detail.
Are both media gases? The general pressure drop requirement is 50 KPA (except in special cases). The flow rate is generally determined by the processing capacity and the inlet and outlet temperatures; moreover, the flow rate requirements vary depending on the type of medium and the position of the equipment in the process, so each case must be treated individually.
To ensure that the fluid is in a fully turbulent state as it flows between the plates, it is advisable to maintain an average flow velocity between the plates of 0.3–0.8 m/s; the maximum value should be adopted if resistance constraints permit, in order to increase the convective heat transfer coefficient and reduce equipment costs.
The original poster’s question is too vague: is the medium a gas, one type or both? So I can’t give you an accurate answer to the original poster’s question. Plate heat exchangers are suitable for heat exchange applications with low pressure and low temperatures.
I want everyone to provide explanations based on different operating conditions; I hope everyone will participate actively.
The allowable pressure drop for plate heat exchangers is generally less than 80 kPa; under such conditions, the cost-effectiveness of the heat exchanger is relatively high. Of course, the pressure drop can also be greater than 80 kPa. While this approach increases the heat transfer coefficient and reduces the heat exchange area, it also leads to significantly higher energy consumption, which in turn increases the investment required for power equipment – making it uneconomical. The value of 80 kPa as a threshold was determined through extensive experience and calculations, so no further explanation is needed here. As for the issue of flow velocity, it is known that the pressure drop is related to flow velocity, the density of the fluid, and its dynamic viscosity; therefore, different fluids will have different flow velocities when the pressure drop remains the same. Moreover, calculations are now done directly using software; generally, it is sufficient to know the physical properties of the gas, as well as its temperature and pressure. There is no need to calculate the flow rate, so most people don’t pay much attention to this parameter. Please forgive any mistakes in my personal opinion. This post was last edited by wfw960209 on 2009-2-16 08:41
This also has a lot to do with the equipment and materials used by the manufacturer; the data provided can only be used as a reference