Abstract
In this study, the cryogenic performance of a regenerator that utilizes fibrous media is estimated. The decrease in the specific heat of the matrix causes a loss of thermal efficiency in cryogenic regenerators. Water vapor condenses in regenerators as frost, which is one of the serious problems in cryogenic air separation plants. A single-blow experiment and numerical analysis considering the effect of temperature dependence on thermal properties as well as the effect of phase change of water vapor were performed. Good agreement of the temperature time variation in the regenerator was obtained for experimental and numerical results. The decrease in specific heat of the matrix causes a loss in efficiency, especially when the switching period is long. Furthermore, the evaporation and condensation of water vapor in a regenerator is simulated under the condition of continuous operation. It was calculated that frost deposition occurs where the temperature gradient is large, and the amount of frost increases linearly with operating time. The drying process is needed once a day for the present condition. The interval increases for lower inlet temperature and higher gas pressure.
