This research project is needed to improve moist air-to-refrigerant evaporator performance under frost growth conditions by minimizing the frost growth and mass of frost, which would lead to improved cycle efficiency and performance. In some heat pump applications, frost accumulation causes a reduction of the refrigerant charge in the evaporator, due to the heat transfer reduction and the resultant expansion valve restriction of the refrigerant flow. The objective of this research project is: 1) Perform a literature search of applicable techniques to reduce frost accumulation as affected by fin staging and partial cutting of fins; 2) Evaluate the potential effect of previously published techniques and evaluate further potentially beneficial fin staging and fin cutting arrangements for minimizing frost accumulation.3) Select the four most potentially beneficial and reliable techniques for further investigation; 4) Perform experimental investigations to verify the frost accumulation effects and applicability of the four chosen methods in minimizing the effects of frost accumulation.

Principal Investigator: Dennis O'Neal, Texas A&M University

Conducted: April 1998 - Nov. 2000

Sponsored by: TC 8.4, Air-to-Refrigerant Heat Transfer Equipment