Shell-side heat transfer enhancement for shell-and-tube heat exchangers by helical baffles

Shell-and-tube heat exchangers (STHXs) have been widely used in many industrial processes such as oil refining, environmental protection, electric power generation, refrigeration and chemical engineering, etc. because of their easy maintenance and possible upgrades. However, the shell-side heat transfer performance is usual unsatisfactory for traditional segmental baffles due to the existence of dead region. In the present paper, the recent development on shell-side heat transfer enhancement for shell-and-tube heat exchangers with helical baffles is reviewed. The main contributions on the shell-pass heat transfer performance include the continunous helical baffled STHXs, single shell-pass combined helical baffled STHXs, combined parallel multiple shell-pass STHX with continuous helical baffles and combined serial multiple shell-pass STHX with continuous helical baffles. These helical baffles changed the flow pattern, simplified the manufacturing process of continuous helical baffles. These new improved STHXs might be used to replace the conventional STHX with segmental baffles in industrial applications to save energy, reduce cost and prolong service life.