Examining the Performance of the Heat Exchanger in a Heat Pump Clothes Dryer

Abstract

The performance of the newly designed fin and tube heat exchanger placed within the heat pump tumble dryer (HPTD) has been numerically and experimentally investigated. A new heat exchanger (HX) has one inlet and one outlet for the refrigerant side. However, after insertion into the evaporator, the flow splits into two different branches and reaches a lower pressure than the standard one. Also, due to the separation more tube bundles can be fitted in the same amount of volume. Due to increased tube bundles, total heat transfer is increased. This behavior can be seen with numerical and experimental results. Also, the fin structures on the heat exchanger were removed from the model to avoid increasing the solution grid density. In this region, it was defined as a porous structure to accommodate the pressure drop. To solve the problem, the program called ANSYS-FLUENT was utilized to solve the problem, and the PISO algorithm was employed to solve the pressure-velocity pair. While air at a specified temperature was passed around the exchanger, water was circulated on the inner surface instead of the refrigerant gas to observe the temperature change.