FLASHING WATER-FLOW THROUGH A SAFETY VALVE

This paper presents an analysis of flashing and non-flashing water flo ws through a safety relief valve. A set of experiments has been carrie d out on the CROSBY safety valve and its model. The pressure distribut ions inside the valve, the inlet and outlet temperatures and the mass- flow rates (critical or otherwise) have been measured. The characteris tics of the valve giving the mass-flow rate as a function of the squar e root of the pressure drop are given. The experimental results are co mpared with equilibrium and relaxation two-phase flow models. The non- equilibrium character of fast evaporation and its substantial influenc e on the two-phase flow behaviour are demonstrated.