冷却空洞の壊縮水撃の熱伝達を組み込んだモデル解析

抄録

A water hammer in collapse of a cooling cavity is modeled and formulated by making well-connections between the water hammer in liquid pipelines and the thermodynamics in the cavity, as a combination of the rigid column theory with the piston-cylinder system and in consideration of the gas in the cavity as moist air. Transient responses of the variables are calculated numerically, including the equation of energy and the term of heat transfer, with a correction for the area of heat transfer to the cavity shape and the identification of the coefficient of heat transfer on the basis of numerical stability. The high-damping waveforms of pressure fluctuation recorded in the experiment, which are not reproducible in the case of using only pipe friction and valve loss, are simulated adequately. Some physical interpretations for the numerical solutions are given and the dependency of solutions on the initial air concentration in the cavity is discussed.