The (one tube) straight tube heat exchanger (STHE) has the same mass flow rate as the HCHE, but still has a less heat transfer rate compared to the STHE from the above CFD Analysis tests.
So if the STHE tube length is changed to 1500mm and inserted into a shell of 1400mm length and the analysis is carried out, the result will show that the (1500mm single tube) STHE also has a less heat transfer rate compared to the HCHE. It is clearly seen that though both the helical and straight tubes are designed of the same length and area, but still the HCHE is more effective in performance.
So due to the turbulence effect in the HCHE there is more effective heat transfer taking place, compared to the STHE.
The effectiveness of the HCHE is 0.628 and the effectiveness of the STHE is 0.25.
The greatest advantage of the HCHE is that, the helical coil can accommodate greater heat transfer area in a less Space, with higher heat Transfer coefficients.
The effectiveness of the HCHE obtained is 0.628, so to increase the effectiveness of heat transfer, the no.
In the present paper CFD Analysis is carried out for comparing the heat transfer performances of both the STHE and HCHE. The extension of this work is to analyze the heat transfer performance of a HCHE with multiple helical tubes in a single shell in order to increase the mass flow rate and performance.
4: HCHE Design file imported in GEOMETRY section of the ANSYS Fluent 14.5 software