Performance improvement of tubular heat exchangers by helical baffles

An investigation into the flow pattern in the shell side space of tubular heat exchangers has revealed a potential for improvement of the heat transfer performance in at least two respects. First of all, a proper arrangement of circle-sector shaped plates into a pseudo-helical baffle causes near plug flow conditions within the shell space with increased heat exchanger effectiveness. Secondly, the rotational flow induced by helical baffles creates a vortex which interacts with the boundary layer on the tube surface and favourable affects the film heat transfer coefficient. These effects are achieved with little increase in pressure head. (author).