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

摘要

The effect of condensate accumulation and shedding on the air-side thermalperformance of automotive evaporator coils has been studied. Experiments under wet anddry 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 toquantitatively determine how condensate load up on a coil surface. Sensible Colburn jfactors and friction factors were calculated from the experimental data, and the relativeperformance of different coils was discussed. A dynamic drainage test was developed tostudy the nature of water draining out of a heat exchanger. It was found the simpledrainage test qualitatively predicted how much condensate would be retained by differentcoils under operating conditions. Current retention modeling techniques were adapted toinclude automotive evaporators.