Numerical Study of Heat Transfer in an Air-to-Air Heat Exchanger Integrated with a Thermoelectric Heat Pump

Abstract

The main objective of this study was to propose a thermoelectric heat-pump unit design for integration with an air-to-air heat exchanger as an air-condenser or evaporator, and to estimate the heat exchanger effectiveness and outlet air temperature based on numerical analyses. Accordingly, a numerical model was investigated to estimate the effectiveness of the crossflow heat exchanger. The heating and cooling sources of the thermoelectric module (TEM) were in direct contact with the airstream from the thermoelectric heat pump (TEHP) unit. Flat-plate fin types were used, which are commonly used in simple heat exchangers to increase the heat transfer area. The numerical model was developed in MATLAB to estimate the heat transfer effectiveness and the air temperature of the outlet side. Numerical analyses were conducted with the proposed model in twodimensions. The numerical simulation results were compared with actual data obtained from a prototype TEHP unit to validate the proposed model. The results showed that the outlet air temperature and fin effectiveness were associated with 20% error bounds. This numerical simulation model can be used as a tool for the consideration of the heat transfer effectiveness and outlet temperatures in the design of heat exchangers that are attached on the thermoelectric module.