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The present study has been carried out to predict the heat transfer characteristics near the door gasket of a residential refrigerator. Temperature measurement and numerical heat transfer analysis were conducted and compared to each other to achieve a more proper numerical analysis method. Three cases of numerical analysis were tried while changing the boundary conditions. The calculated result of temperature using a uniform free stream temperature showed a great difference from the measured temperature. The numerical result including two dimensional fluid flow was also shown to be far from the measured result. The measured temperature had periodic characteristics which were divided into two parts, an increasing part and a decreasing part during an 18 minute period because of the operation of compressor in a refrigerator. The heat transfer might contain three dimensional forced and natural convective heat transfer phenomena near the door gasket. Instead of adopting the complicated three dimensional numerical analysis the two dimensional heat transfer analysis with the measured free stream temperature derived more accurate temperature prediction than the other numerical analyses.

The present study has been carried out to predict the heat transfer characteristics of a residential refrigerator through insulation wall by using reverse heat loss method. The temperature time history characteristics were measured to achieve the steady state condition. In this experiment the steady state condition was reached at about 20 h of heating. The temperature and heat inputs were then averaged with one hour data and considered as the steady state temperature and heat input. From the measured values of temperature and heat input, one can conclude that, the temperature differences between the inside and outside of a refrigerator has a nearly linear relationship with heat input. The overall heat transfer coefficients have been derived by introducing the optimal heat loss function to analyze the heat loss characteristics. The accuracy of heat loss prediction has been checked with various experimental data and the normalized errors of the obtained result are found to be within 2.5%.

An infrared thickness measuring technique for thin film coated on the metal mold was developed and applied to thickness measuring of the artificial breast implant pack. The infrared light emitted from a metal mold itself was partly absorbed to the silicon film, and the remainder of the infrared light was transmitted through the film. The relationship between the thermal image captured by an infrared camera and the film thickness was analyzed. The thicker the film, the bigger the amount absorbed. The new infrared thickness measuring technique agreed well with the results directly measured by a microscope when applied to the artificial breast implant pack.