Thermal Performance Investigation of Plain Finned-Tube Evaporators Used in Household Refrigerator

Özet

In this study, thermal performance ofplainfinned-tube evaporators in household refrigerators are investigated numerically and experimentally. The design parameters affecting on the cooling capacity are determined as air flowrate, evaporator temperature, tube alignment, number of tubes and number of fins. In the initial stage,the effects of those parameters on the cooling capacities are simulated by CoilDesigner software. The number of experiments that are necessary to obtain correlationsis determined by Minitab software. The experiments are carried out in a no-frost household refrigerator in the off-mode. At the end of each experiment, air side heat transfer coefficients are calculated to generateaNusselt(Nu) correlation as a function of the mentioned design parameters. The generated correlationof the cooling capacity canpredict95% of the experimentalresults within a confidence range of 15%. The correlation of the cooling capacity is converted to the Nusselt number correlation which is found to be consistent with available data in literature. The experiments reveal that the cooling capacity is dominantly affected by the evaporator temperature followed by air flow rate, tube alignment, number of tubes and thenumber of fins.