Helical configuration for thermoelectric generation

Performance of thermoelectric (TE) generator (TEG) depends on its physical structure in addition to the properties of TE materials. This study numerically simulated the characteristic performances of a three-dimensional (3-D) helical TE module using finite-volume method, and compared them with those of a conventional straight module. The effect of geometric parameters of helical TE module on the characteristic performances was analyzed, and an optimal helical design was proposed to obtain higher performance. The simulation results show that the helical module can harvest more heat than the straight module, and thus generate higher output power because the conversion efficiencies of two modules are approximately equal. The increase in pitch of the helical module has a positive influence on the characteristic performances, including more heat harvesting and output power, as well as higher conversion efficiency. However, the radial expansion of helical module brings an opposite effect on the unit performances, which is defined by dividing the characteristic performances by the number of p-n pairs, and unit input heat, unit output power, and unit heating area of helical module are decreased with module diameter. Higher performance can be generated by the use of helical module with longer pitch and shorter diameter.