Similarity of Heat Transfer on Heat Source Elements in the Entrance Region in Electronic Equipment

AsimilarityequationforheattransferonheatsourceelementssituatedintheentranceregioninelectronicequipmentisdevelopedbasedontheexperimentaldataobtainedbySparrowetal.^[4].ThecharacteristicofthesimilarityequationisthattheratiooftheheattransfercoefficientattheentranceregiontothatatthefullydevelopedregionisindependentoftheReynoldsnumber.Itdependsonlyontherownumberoftheelementssituatedintheentranceregion.Anexampleoftheusefulnessofthesimilarityequationispresentedthatdeterminestheheattransferonheatsourceelementsinapowerunitthatcontainsonlyasmallnumberoftheheatsourceelements.