Plate fin heat sink modelling and design considerations for thermoelectric generators

Abstract

This paper presents the developed model for the analysis of thermoelectric generators (TEG) with a plate fin heat sink with forced convection at the cold side. In the first part, an analytical model is created for a TEG with a constant temperature at the hot junction and a variable thermal resistance at the cold junction of the TEG. The influence of varying the thermal resistance and the electrical load on the power output and efficiency of the module is simulated. The results show that the optimal electrical load is a function of the thermal resistance. Next the influence of several design parameters of the heat sink is analyzed. The generated power by the module and the required fan power for the cooling is evaluated to achieve maximal net power output or net thermal efficiency. From these analyses several design guidelines are formulated. The net power output shows an optimal value in function of the air flow rate. Furthermore, the influence of the limits of different manufacturing techniques of plate fin heat sinks on the performance of the TEG is simulated. This shows that the theoretical optimal fin thickness and fin gap is not achievable for all industrial manufacturing techniques.