A nonisobaric supersonic jet of vibrationally excited carbon dioxide exhausting from converging axisymmetric nozzles with the diameter ranging in a wide interval (from 0.03 to 114 mm) is studied experimentally and numerically. Numerical simulations are performed within the framework of the two-temperature approach with the use of the Landau–Teller relaxation equation for each vibrational mode of carbon dioxide molecules. The simulations reveal that the vibrational nonequilibrium of molecules affects the gas-dynamic structure of the jets in the temperature range of 300–900 K, and this effect is verified experimentally. Vibrational excitation of molecules in the experiment is ensured by means of gas heating. The effect of vibrational nonequilibrium is manifested as a reduction of the amplitude of the static pressure in wave structure cells and as a reduction of the longitudinal size and number of wave structure cells as compared to the case of an equilibrium supersonic flow. It is shown that the maximum effect of nonequilibrium is observed in jets exhausting from the nozzle with a diameter of ≅ 3 mm.

对从直径范围较宽（0.03 至 114 mm）的会聚轴对称喷嘴排出的振动激励二氧化碳非等压超音速射流进行了实验和数值研究。数值模拟是在双温度方法的框架内进行的，对二氧化碳分子的每种振动模式使用朗道-泰勒松弛方程。模拟结果表明，在300-900 K温度范围内，分子的振动非平衡会影响射流的气体动力学结构，并且这种效应得到了实验验证。实验中分子的振动激发是通过气体加热来保证的。与平衡超音速流的情况相比，振动非平衡的影响表现为波结构单元中静压振幅的减小以及波结构单元的纵向尺寸和数量的减少。结果表明，在从直径≅ 3 mm 的喷嘴排出的射流中观察到非平衡效应最大。