Performance of a miniature ejector for application in a nitrogen Joule-Thomson cycle: Experimental and numerical analysis

The performance of Joule-Thomson (JT) cryocoolers can be improved by introducing ejectors. Ejectors with various geometric features have been proposed and investigated for cryogenic cooling in earlier studies, but only limited research is done on ejectors a nozzle throat diameter less than 1 mm. In this paper, we present miniature ejector 162 ?m that was measured using X-ray computed tomography. When the operated nitrogen gas at 295 K primary inlet pressure 80 bar, secondary 0.5 bar an outlet 1.2 mass-flow rates were 394 mg/s 83 mg/s, respectively. rate quite close to value predicted dynamic model, whereas lower value, which mainly caused non-axisymmetric machining defect assumed axisymmetric model. Besides, effects operating pressures position analyzed. study demonstrates applicability JT cycle.