Effect of longitudinal vortex generator location on thermoelectric-hydraulic performance of a single-stage integrated thermoelectric power generator

Vortex generators have been widely used to enhance heat transfer in various heat exchangers. Out of the two types of vortex generators, transverse vortex generators and longitudinal vortex generators (LVGs), LVGs have been found to show better heat transfer performance. Past studies have shown that the implementation of these LVGs can be used to improve heat transfer in thermoelectric generator systems. Here, a built in module in COMSOL Multiphysics® was used to study the influence of the location of LVGs in the channel on the comprehensive performance of an integrated thermoelectric device (TED). The physical model under consideration consists of a copper interconnector sandwiched between p-type and n-type semiconductors and a flow channel for hot fluid in the center of the interconnector. Four pairs of LVGs are mounted symmetrically on the top and bottom surfaces of the flow channel. Thus, using numerical methods, the thermoelectric- hydraulic performance of the integrated TED with a single module is examined. By fixing the material size D, the fluid inlet temperature T_in, and attack angle b, the effects of the location of LVGs and Reynolds number were investigated on the heat transfer performance, power output, pressure drop, and thermal conversion efficiency. The location of LVGs did not have significant effect on the performance of TEGs in the given model. However, the performance parameters show a considerable change with Reynold's number and best performance is obtained at Reynold number of Re=500.