Experimental investigation of the thermal-hydraulics of gas jet expansion In a two-dimensional liquid pool

Abstract

Gas jet blowdown in a two-dimensional liquid pool has been experimentally investigated. Two sets of experiments were performed: a set of hydrodynamic experiments, where a non-condensible gas is injected into a subcooled liquid pool; and a set of thermal-hydraulic experiments, where a non-condensible heated gas is injected into a near saturated liquid pool. Liquid entrainment by the gas, bubble growth characteristics, and the potential for vaporization, were investigated for a variety of experimental pressures (3 to 10 bars) and two liquid types (water and R-113). Liquid entrainment increased with increasing pressure. The fraction of the jet volume which is liquid is relatively the same for all pressures and decreases with time of expansion. A Taylor instability mechanism for entrainment is found to under predict the entrained volume. In the initial stages of the expansion, higher entrainment is experienced for more dense fluids. For the same fluid, the entrainment rate was slightly higher for the heated experiments compared to the unheated experiments. Both lateral and vertical growth rates increased with pressure. Vaporization may have occurred for the 4 bar initial pressure, 12 °C superheat condition in freon R-113.