The flow about the outdoor heat-exchanger unit of a heat pump system has been numerically investigated. Using a general purpose analysis code, FLUENT, the Navier-Stokes equations with the standard k-ε turbulence model are solved for the three dimensional computational domain that includes the fan and the finned heat exchanger module. The heat exchanger is modeled by the porous medium that gives equivalent pressure drop while the fan is replaced by the actuator disk using the experimentally obtained fan performance curve.
The procedure is found to be robust and satisfactory as the predicted flow rate for the specific fan RPM of 850 is well matched with the measured data. The details of the flow characteristics are very well captured. The flow fields for various fan speeds and configurations are then examined systematically and the results are presented in the thesis. The optimal heat-exchanger/radiator layout that makes the volume flow rate uniform is also suggested.
