Condensate Retention Effects on the Air-Side Heat Transfer Performance of Automotive Evaporator Coils

The effect of condensate accumulation and shedding on the air-side thermal performance of automotive evaporator coils has been studied. Experiments under wet and dry conditions were conducted to expose the impact of condensate on five different coils. Condensate retention data were collected in both real-time and at steady-state to quantitatively determine how condensate load up on a coil surface. Sensible Colburn j factors and friction factors were calculated from the experimental data, and the relative performance of different coils was discussed. A dynamic drainage test was developed to study the nature of water draining out of a heat exchanger. It was found the simple drainage test qualitatively predicted how much condensate would be retained by different coils under operating conditions. Current retention modeling techniques were adapted to include automotive evaporators