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This thesis presents a hybrid numerical scheme for the inverse heat conductionproblem and an experimental equipment to estimate the heat transfer coefficient and fin efficiency on the Plate Finned-Tube Evaporator under frosting conditions. Thus, the comparison of the heat transfer rate and fin efficiency obtained by the assumption of the constant heat transfer coefficient and the exact values is made. Afterward, the scheme of the inverse heat conduction in conjunction with temperature measurements at various times and various sensor locations is presented to estimate the heat transfer coefficient on the fin.To evidence the accuracy of the present scheme,the comparison of the present estimations and exact values is made.In addition, the effect of the measurement error and sensor location on the estimated results is also be studied. We set up a plate finned-tube evaporator in conjunction with the other experimental equipments for measuring the frost thickness and fin temperature. The heat transfer coefficient, heat transfer rate and fin efficiency on the fin under frosting conditions can be determined using the present method and these temperature measurements. In addition, the effect of relative humidity of the air, refrigerant temperature and air temperature on the frost growth, heat transfer coefficient,overall heat transfer rate and fin efficiency is also investigated. This tesis can present some information for the relation between the frosting phenomenon and performance of the evaporator under various operation conditions. We hope that its results are useful for the design of the refrigeration and air condition system.
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