Calculation of heat exchanger efficiency
Thread Content
There is a heat exchanger. For the hot fluid: the designed inlet temperature is T1, and the designed outlet temperature is T2; in actual operation, however, the actual inlet temperature is T3, and the measured outlet temperature is T4. For the cold fluid: the designed inlet temperature is T5, and the designed outlet temperature is T6; in actual operation, the actual inlet temperature is T7, and the measured outlet temperature is T8. How can one calculate the decrease in the heat exchange efficiency of the heat exchanger? How to set up the equation?
If the high-temperature outlet temperature cannot be reduced and the low-temperature outlet temperature cannot be increased during operation, it indicates that the heat exchange efficiency of the heat exchanger has declined
:) Friend, when comparing the actual situation with the design, it’s probably a matter of the performance in use; so all that’s needed is to calculate the actual heat load and compare it with the original design. Heat transfer efficiency generally refers to the achievement of the specified performance criteria at the design stage, by selecting different structural configurations. Some comparisons are made based on the heat transfer rate per unit area, while others use the effective temperature difference and the pure counterflow temperature difference; there are also comparisons made by using the heat load versus the maximum possible heat transfer amount (when the heat transfer area is infinite). These values are all those that need to be taken into consideration during the design process.
Heat transfer efficiency during actual operation = (T6 – T5) / (T3 – T5), for reference only
It’s just a simple heat balance. Then the efficiency can be calculated! ! ! ! ! ! ! ! ! ! ! !