潜熱蓄熱器の凝固過程における熱特性 : 相似曲線を使った相似関数と熱放出割合との関係の予測法

抄録

A method of predicting the relationship between the similarity function and the heat release fraction has been proposed and applied to the solidification process of an annulus-type storage unit. The concept of this method has been derived from analysis under the quasi-steady approximation. The prediction should be performed in two separate stages of the solidification process individually. In the first stage-prior to completion of the freezing of phase change material-the similarity function vs. frozen fraction curve can be transformed in accordance with the fact that the heat release fraction is approximately proportional to the frozen fraction. In the second stage after the completion of freezing, where all heat is released as sensible heat, the heat flow rate maintains a linear relation with the heat release fraction. Thus, the similarity function defined in terms of the heat flow rate can be directly correlated with the heat release fraction. The results predicted are in good agreement with numerical calculations.