Vibration modal analysis for a finned-tube heat exchanger based on COMSOL

A finite model for a finned-tube heat exchanger was built and analyzed with vibration modal analysis in COMSOL 3.5. The modeling methods, parameters setting, solve procedures and modal analysis results were detailed introduced, and vibration modal analysis results were discussed. The results show that the vibration modal difference of the heat exchanger is large between the low and high frequency vibration modes. In the low order frequency vibrations, there are big differences between two neighbor eigenfrequencies, and the vibration amplitudes at the eigenfrequencies are large. While in high order vibrations, there are small frequency interval differences, and the vibration amplitudes are far less than that in low-order vibrations; the distribution of the vibration is more uniform. Ultrasonic vibration can be used to excite the heat exchanger to vibrate at high frequency to enhance the heat-exchange efficiency and descaling, it has a poor damage to the heat exchanger.