A simplified model for the aging of gas-filled thermal insulating foams is developed. This model is used to predict gas composition, gas partial pressures, and thermal performance of foams. The coupling between heat and gas transfer is one ofthe characteristic features ofthe model. The temperature dependency of gas perme ability, which has been found in many experimental studies, is taken into account The evaluation showed that the predicted results agree well with the measured ones. Under prescribed conditions ofaging, foam thermal conductivity, temperature, and gas partial pressures in foam can be calculated as a function of time and position.
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