Summary

Frost accumulation in evaporators is an unavoidable and undesirable phenomenon, since it reduces the cooling capacity and the system performance. The capacity depletion takes place because the frost layer not only increases the thermal resistance between the air and the finned tubes but also decreases the air flow passage and thus the airflow rate. As a consequence, the evaporator heat transfer rate decreases followed both by a rise in the cabinet internal temperatures and in the compressor on - time. The frost must then be periodically removed by electrical heaters, with a negative impact both in the thermal load and energy consumption. The need for a better understanding of the frost accumulation process in no - frost evaporators has stimulated several experiment al and theoretical studies on this issue during the past decades. [...]

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