Investigate the Thermal Performance of Shell and Double Coil Tube Heat Exchanger by Numerical Simulation

In comparison with the straight tube, in helical coils, the centrifugal force creates a pair of longitudinal vortices, and this secondary flow increases the heat transfer coefficient. In present study, the influence of two geometric parameters of double coil tube on thermal performance of a shell and double helical coil heat exchanger is evaluated. The investigated geometric parameters are including external coil pitch and internal helix diameter. Water is considered as working fluid in both shell and double coil tube. For comparison of the models, the heat transfer area (coil outer surface) is kept constant in all studied models. The results show that the use of two helical coils, as well as the geometric changes in the coil, will significantly increase the heat transfer rate. As a result, the highest thermal efficiency associated with the external coil pitch of 60 mm in a Reynolds number of 5307 which has the best thermal performance compared to the other pitches. Also, the highest thermal efficiency is related to the internal helix diameter of 240 mm.

کلیدواژه ها:

Heat Transfer ، Shell and Coil Tube Heat Exchanger ، Thermal Performance