Thermoelectric devices offer the potential to convert wasted heat into electricity, and they can be used for thermal management by pumping heat. The advent of new manufacturing techniques such as additive manufacturing enables customizable thermoelectric device shapes. However, there is little knowledge about what shapes are beneficial in applications with differing thermal conditions. This work determines the effect of different thermoelectric leg designs on thermoelectric device performance. Various leg shapes (rectangular prisms, prisms with interior hollows, trapezoids, hourglass, and Y-shape) were modeled numerically to determine their thermal and electrical performance under constant temperature and heat flux boundary conditions. Two thermoelectric materials, bismuth telluride and silicon germanium, were modeled to capture both low and high temperature application cases, respectively. An hourglass-shaped thermoelectric leg with a constant hot side temperature, has the best thermal and electrical performance. The hourglass-shaped leg results in more than double the electrical potential and maximum power compared to the conventional rectangular shape when the cold side experiences a natural convection boundary condition. With a constant hot side heat flux, a reverse trapezoid-shaped leg results in almost double the electrical potential and a 50% increase in the power output compared to the conventional leg shape. In particular, this work shows that considering leg shape alone is insufficient: varying boundary conditions (which reflect different device operating conditions) result in different performance values for the same leg shapes. These findings underscore the importance of leg geometry on electrical and thermal performance of a thermoelectric leg, as well as the importance of considering the device operating condition when selecting the best leg shape.

热电设备具有将浪费的热量转化为电能的潜力，并且可以通过泵送热量将其用于热管理。诸如增材制造之类的新制造技术的出现使可定制的热电器件形状成为可能。但是，对于哪种形状在不同热条件下的应用中是有益的却知之甚少。这项工作确定了不同热电腿设计对热电设备性能的影响。对各种支腿形状（矩形棱柱，具有内部凹陷的棱柱，梯形，沙漏和Y形）进行数值建模，以确定它们在恒定温度和热通量边界条件下的热和电性能。两种热电材料，碲化铋和硅锗，被建模为分别捕获低温和高温应用案例。具有恒定热侧温度的沙漏形热电腿具有最佳的热和电性能。当冷侧经历自然对流边界条件时，与传统的矩形形状相比，沙漏形的腿产生的电势和最大功率要高出一倍以上。与常规的腿形相比，在恒定的热侧热通量的情况下，倒梯形腿的电位几乎提高了一倍，功率输出增加了50％。特别是，这项工作表明仅考虑腿部形状是不够的：改变边界条件（反映不同的设备操作条件）会导致相同腿部形状产生不同的性能值。