Novice, what factors can be changed to change the heat transfer coefficient?
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Novice, what factors can be changed to change the heat transfer coefficient when designing?
I personally don’t know much about heat exchanger design. I have seen a related information, which may only provide part of the relevant information, not necessarily all of it.: Another thing we know is that the length of the heat exchanger tube bundle is generally 6 meters. After design calculation, almost the same heat exchange area is used. Some use one heat exchanger (the diameter of the heat exchanger is larger), and some use multiple heat exchangers in series (the diameter of the heat exchanger is smaller). In addition to being limited by the maximum diameter of the heat exchanger, this should be different in the relationship between the medium flow state and the heat transfer coefficient, as well as the final heat exchange temperature.
Flow rate, pipe diameter, material, wall thickness, pipe length (affects pressure drop and heat transfer coefficient), heat exchange pipe layout, shell size, number of baffles, baffle type, baffle shear rate, whether there are baffles, etc., etc., etc., etc. . .
Analyze the heat transfer resistance of the heat exchanger, which generally consists of four parts: Tube side thermal resistance, shell side thermal resistance, dirt thermal resistance, material thermal resistance, whichever side has greater heat transfer resistance, the better effect is to strengthen and change it. Dirt and materials are generally fixed, only the tube side and shell side can be changed. Strengthening the pipe process is generally to increase the medium flow rate. The main means are:: Increase the pipe length and increase the pipe distance. Means to improve shell side heat transfer include: Change the diameter, baffle type and quantity, change the heat exchanger type, etc.
After reading the question... Basically, the so-called heat transfer coefficient should refer to the coefficient of heat conduction, which basically depends on material design, etc. But today, if we consider how to improve the efficiency of heat transfer, the following methods are provided: 1. Increase the heat transfer area 2. The fluid should be as clean as possible 3. The dirty fluid runs on the pipe side 4. Use a heat exchanger with better heat transfer Exchangers such as plate type, shell plate type, etc. 5. Pipe bundles should use pipelines with high heat conduction efficiency. 6. The flow rate of the fluid should not be too fast or too slow. Finally, each variable will make your heat exchange efficiency high or low, and may also cause blockage and corrosion, so it should not be considered unilaterally... The above opinions provide reference
In terms of structure, it means materials and tube form specifications.