2021 Volume 47 Issue 6 Pages 200-205
In order to construct a metal hydride heat pump system that is active at subzero temperatures, this study aimed to estimate temperature rise from the equilibrium hydrogen pressure. Temperature rise experiments of dry heating and water heating were carried out using a heat-driven metal hydride heat pump. As a result, the characteristics of two types of alloys could be expressed in terms of the exponent of the state quantity ΔPA and the state change ΔTB in the heat pump operation before the temperature rise. A prediction formula was created based on the experimental values of the temperature rise from the reaction characteristics of the two storage alloys during the chemical reaction, the change in the hydrogen pressure in the container, and the temperature rise of the alloy. In the water heating experiment, the metal hydride was cooled by putting water around the alloy storage container, and the capacity for storing hydrogen was maintained, so that the calorific value was larger than that in the empty-fired state.
