Enhancement of the cooling of shear-thinning fluids in channel heat exchangers by using the V-baffling technique

The present work is a study of the performance of a channel heat exchanger equipped with V-baffles. The study is carried out numerically by using a multidimensional CFD model (the Software ANSYS CFX v.18). Among the different techniques available to improve the efficiency of heat exchangers, we choose in this work the technique of vortex generators (baffles). The simulated fluid is a complex shear-thinning solution and the flow regime is laminar. The influence of some parameters on the efficiency of such heat exchanger has been verified, namely the flow rate (Reynolds number), the orientation of baffles and their arrangements. Two orientations of baffles are selected: +V and -V, corresponding to the counter direction of flow and the same direction of flow, respectively. Also, the staggered and aligned arrangements of +V baffles are studied. The predicted results revealed that +V baffles inserted in the staggered arrangement may give a considerable superiority in enhanced heat transfer ratio, compared to the (-V) baffles' insertion and the aligned arrangement. Values of the thermal performance factor for the +V aligned arrangement, -V aligned arrangement and +V staggered arrangement of baffles are: 1.44, 1.32 and 1.52, respectively.