Enhancement of a steam-jet refrigerator using a novel application of the petal nozzle

This study applies a petal nozzle to enhance the performance of a steam-jet refrigeration system. The behavior and characteristics of a petal nozzle are also investigated by testing it under various operating conditions, i.e., generator temperature, evaporator temperature and condenser temperature. In addition, the effect of area ratio (AR of constant area section of ejector to nozzle throat) on ejector performance is studied by testing ejectors with various values of AR. For comparison, a conventional conical nozzle with the same Mach number as that of petal nozzle is also used. Experimental results demonstrate that the compression ratio and the entrainment ratio can be enhanced if the petal nozzle in an ejector with a larger AR value is used. Moreover, for the ejector with a petal nozzle, an optimum AR value exists under which a maximum compression ratio can be found.