Heat Transfer Enhancement in Absorber Tube of Parabolic Trough Concentrators Using Wire-Coils Inserts

Abstract

Heat transfer enhancement technology provides many advantages in heat exchanger applications. In the present paper, the heat transfer characteristics and the pressure drops of the absorber tube of Parabolic Trough Concentrators with wire-coils inserts are investigated. Water is used as a heat transfer fluid and simulations are carried out in COMSOL Multiphysics® 4.4, for various flow rates of water as well as for different pitch values of wire-coils insert. It is observed that introduction of wire coils increases the turbulence inside the tube, thereby increasing the Reynolds number and hence the Nusselt number. Value of Nusselt number is observed to be increased by 104% to 330% which indicates the increase in the value of convective heat transfer coefficient and hence the heat transfer rates.