In order to obtain a suitable shape curve of the CO₂ adjustable ejector regulating probe for automobile air conditioning, this paper proposed three kinds of probe schemes including linear, concave and convex probe based on the Homogeneous Equilibrium Model (HEM), and the analyzed changes of the ejector flow rate and elicitation ratio in the process of probe movement with the aid of the Computational Fluid Dynamics (CFD) tool, and compared the differences in the performance of the adjustable ejector with the three kinds of probe schemes. The results show that: When the probe radius at the throat is small, with the increase of the probe radius at the throat, the entrainment ratios of the ejector of each scheme increase slowly due to the decrease of the primary flow rate, and when the probe radius at the throat exceeds the high efficiency adjustment radius, the entrainment ratios of the ejector of each scheme decrease dramatically until they can’t be induced; compared to the other 2 probe schemes, the concave probe scheme has a larger entrainment ratio within the high efficiency working area, and it has a stronger overall performance.

Automotive air conditioning  /  Adjustable ejector  /  Homogeneous equilibrium model  /  Two-phase flow