Abstract
In recent years, for the purpose of optimizing the heat transfer and pressure drop characteristics, the CFD analysis method of finned tubes have been developed and the heat transfer coefficient distribution on a fin surface was revealed. However, there are few measured results because the heat transfer coefficient distribution can not be measured in detail by traditional steady-state method. In the present study, we introduced a new method which is non-contact, transient technique to measure the heat transfer coefficient distribution. Since conventional transient technique assumed a test model as a semi-infinite flat plate, error occurs when applying to the finite thickness flat plate. To resolve the problem, we applied the unsteady-heat-conduction equation in consideration of a fin thickness to evaluate a heat transfer coefficient. The measurement was carried out in the condition of Reynolds number Re=1.6×10^4. And the result was compared with the numerical analysis. We consider that this transient technique is also better to minimize a measuring period and cost than traditional steady-state measurement method which need finned tubes made by metals.
