Analytical model for calculating pressure rise in a room due to refrigerant spills from piping rupture

摘要

In this paper, an analytical model is presented to describe quasi- steady release of a two-phase refrigerant mixture into a room and the associated pressure transient of the room atmosphere with limited capability to discharge the atmosphere. The analytical model is based on simple, approximate thermodynamic relationships applied along isentropes, which is used to describe the release of refrigerant and the coupled set of equation of energy and mass conservation and other auxiliary equations describing pressure transient of a room atmosphere. The analytical model, which consists of a set of nonlinear ordinary differential equations, is solved numerically by the Mathematica computer program. As an example the safety problem of a Freon-22 spill in a refrigeration equipment room, resulting from piping rupture due to an earthquake, is analyzed and discussed.