Performance comparison of TEGs for diverse variable leg geometry with the same leg volume

Highlights: • Difference of the internal temperature distribution with the variable leg geometry. • Internal resistance and thermal conductivity is influenced by the geometry of leg. • Diverse variable leg geometry with the same leg volumehave an effect on performance of (TEG). The product development process consists of all the steps required to transform a product from concept to market availability. The volume used to make a product is one of the most important factors affecting the final price of a product and has to be taken into account in the design stage. In this context, a study based on the finite element method was carried out using different geometrical shapes of the same volume by considering the five following shapes: rectangle, I-leg, X-leg, trap-leg, and Y-leg. To achieve this, two cases were examined. In the first case, all five shapes of the same volume (47.915 mm³) were studied by considering an identical length of X-leg (6 mm) and the variable cross-sectional area of the hot ceramic junction. The results obtained show that the rectangular leg model generates the highest efficiency and output power with 5.482% and 0.041 W respectively. In the second case, all shapes of identical volume (47.915 mm³) were analyzed by condensing a variable leg length and a fixed cross-sectional area of the hot ceramic junction of X-leg. The results also show that the rectangular leg model generates the highest output power, which is approximately 0.114 W. In addition, in order to optimize the best model found, the length of the legs allowing to obtain the optimal internal resistance and thermal conductivity has been determined. The findings indicate that the rectangular leg model with a leg length of 6 mm gives the best performance.