AN EXPERIMENTAL INVESTIGATION OF COOLING OF A LOW PRESSURE, LOW TEMPERATURE AIRSTREAM USING LIQUID AIR INJECTION

An investigation was conducted to determine the feasibility of producing a low temperature, uncontaminated airstream by injection of liquid air into a primary airstream. Steady-state data were obtained with primary airflow conditions generally set at total pressures from 2.5 to 5 psia and supply air temperatures ranging from 380 to 540 R. Liquid airflow rates ranged from 0 to 13.5 lbsec. Temperature drops of the primary airstream up to 85 R were recorded with liquid air-to-primary air ratios up to 0.146. Calculated cooling efficiencies ranged from 75 to 100. Gas samples obtained in the mixing chamber at locations 10 and 24 ft downstream from the injection station indicated that the gas flow was a homogeneous mixture with the O2 and N2 content of the gas samples dependent upon the proportions injected.