Multiphysics field coupling simulation for shell-and-tube heat exchangers with different baffles

Baffles are important components to control shell-side flow distribution and enhance heat transfer for shell-and-tube heat exchangers (STHXs). Based on multiphysics field coupling simulation, thermal–structural performance was studied for three types of STHXs with different baffles including segmental baffles, plain helical baffles and fold helical baffles. The results show that zigzag flow appears in STHXs with segmental baffles, and flow behavior is helical pattern in STHXs with helical baffles. Especially, much vortex and high velocity are generated in STHXs with fold helical baffles, where the shell-side pressure drop and Nussult number are the highest, and thermal enhancement factor (TEF) to evaluate thermal–hydraulic performance is also the largest. Although higher von-Mises stress distributes on the tube bundle, results of stress linearization at dangerous location in elastic stage show that membrane stress and sum of primary stress and secondary stress are both within range of corresponding stress intensity. Therefore, the comprehensive thermal–structural performance of STHXs with fold helical baffles is the best. The research can have a degree of theoretical guidance for design and choice of heat exchangers.