Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.
In order to simplify the manufacture and improve the heat
transfer performance, we have invented a combined multiple
shell-pass shell-and-tube heat exchanger. The novel combined
multiple shell-pass shell-and-tube heat exchanger (CM-STHXs)
with continuous helical baffles in the outer shell-pass and other
different baffles in the inner shell-pass was compared with
conventional STHX with segmental baffles by Computational
Fluid Dynamics method. The numerical results show that, under
the same mass flow rate M and the same overall heat transfer
rate Qm in the shell side, the CM-STHX with discontinuous
helical baffles in the inner shell-pass has the lowest overall
pressure drop DP, which was 13% lower than that of the
segmental baffled STHX; The heat transfer rate Qm of the
CM-STHX with discontinuous helical baffles in the inner
shell-pass is about 2% and 12% higher than those of the
CM-STHX with segmental baffles and disk-and-doughnut
baffles in the inner shell-pass. The CM-STHX with
discontinuous helical baffles in the inner shell-pass has a much
better heat transfer performance and can be used to replace the
conventional STHX with segmental baffles in industrial
applications to save energy, reduce cost and prolong the service
life.
