An Experimental Study of Heat Transfer During Forced Air Convection

Cast aluminum alloys are usually subject to solution treatment, quenching, and aging hardening for improved mechanical properties. Cooling rate during quenching plays an important role in residual stress, distortion, and mechanical property distributions in the resultant cast aluminum components. As the cooling rates of work pieces heavily depend on the interfacial heat transfer coefficient (HTC) between work pieces and quenchants, it is important to understand how HTC varies with different quenching conditions so that optimal quenching process can be achieved. In this study, a quenching system and an experimental procedure of obtaining HTC are presented. A series of experiments have been conducted to study the variations of HTC with respect to air temperature, air humidity, air velocity, and part orientation.