experimental study on thermal local entropy generation in u-shaped channel

This paper studied the amount of entropy generation in u-shaped channel experimentally. the experimental tests included the variation in heat flux, inlet temperature and volume flow rate. the laboratory data for this channel was solicited and assessed by the equations of thermal entropy generation. the radial pressure gradient is responsible for inducing two important factors in the process of increasing the heat transfer coefficient and reducing entropy generation. one of these factors along with the flow makes the fluid axial velocity to approach the wall and the other in the cross-section generates secondary flow circulations. finally, the wall temperature decreases and the coefficient of heat transfer increases. the variations in entropy generation decrease with the increase in mass flow rate and inlet temperature and increase with the increase in heat flux.