| 摘要 |
PURPOSE:To maintain a supercooled gel state of a heat accumulating medium and to enable utilization of heat with certainty when necessary, by providing at the vapor-liquid interface of a specified heat accumulating medium a liquid composition which prevents the contact of the heat accumulating medium with a vapor phase. CONSTITUTION:The evaporation of the moisture of a heat accumulating medium 2 into the air is prevented by a liquid composition 5 (e.g., an oil film) provided at the vapor-liquid interface of the heat accumulating medium 2 containing a salt which undergoes reversible phase transition between a more hydrated gel phase and a less hydrated crystal phase with evolution or absorption of latent heat (e.g., hydrated sodium acetate containing 41wt% water). Therefore, the formation of crystals of the medium 2 at the interface will not take place, and the medium 2 will maintain its supercooled state stably even if the tempera ture decreases so that heat accumulation can be effected with certainly. When heat is needed, a heat generating unit 4 is operated to move its pointed end through the composition 5 into the medium 2, which is thereby stimulated to form nuclei and to be crystallized wholly in a short time. This phase transition yields a latent heat, which is transmitted to cold water running in a pipe 3. |
