Transient thermal stress analysis of a thermoelectric cooler under pulsed thermal loading

摘要

A three-dimensional, nonlinear, and dynamic finite element model coupling the thermal, electrical, and mechanical fields was established to investigate transient thermal stress of the integrated thermoelectric cooler (TEC) under the pulsed thermal load. The model considered the temperature-dependent material properties. Results showed that pulsed thermal loading reduced the cooling performance of the TEC and caused the dramatic variations of temperature and thermal stress in the device. With a pulse load of 30 W, the chip temperature fluctuation amplitude was about 170 degrees C and the fluctuation amplitude of the thermal stress at the contact interface between the chip and TEC reached 686 MPa. The fluctuations amplitudes increased with pulse amplitude and time. Using the TEC's transient supercooling characteristics to relieve temperature and thermal stress peaks appeared effective, which could be utilized to improve the robustness and functionality of TEC for the electronics cooling.