Abstract. Results of comprehensive experimental studies on modeling jets of low-thrust liquid-propellant rocket engines (LPREs) under vacuum conditions are presented; the studies were conducted at the Kutateladze Institute of Thermophysics, Siberian Branch of the Russian Academy of Sciences (IT SB RAS). Engines of this class, with thrust in the range from 5 to 4000 N, serve as a key element in attitude control and orbit correction systems of spacecraft and orbital stations. The research was carried out using the unique scientific facility – the Vacuum Gasdynamic Complex of IT SB RAS – which includes the large-scale vacuum gasdynamic chamber VIKING. This facility enables the study of rarefied gas jets under conditions simulating the real space environment. The methodological foundations of modeling are examined in detail; they are based on preserving the integral gasdynamic characteristics of jets, including the characteristic expansion angle and relative impulse. Special attention is given to three main types of jet impact on spacecraft structures: force, thermal, and physicochemical (contamination). Modeling criteria have been developed and validated, accounting for both gas and droplet phases of the flow. The results have been systematized for various thruster configurations used in Russian and international space programs. The fundamental mechanisms of plume backflow formation were identified, and effective gasdynamic protective devices were developed to minimize them. The research methodology included modern diagnostic techniques, among them electron beam diagnostics and laser stroboscopy. The results of the model studies were successfully compared with data from full-scale on-orbit experiments at the International Space Station, confirming the reliability of the applied methodology and the effectiveness of the proposed technical solutions. The developed protective devices reduced the contamination of the station’s external surfaces by products of incomplete propellant combustion by several orders of magnitude, increasing its operational reliability. The results contribute to the development of fundamental science in the field of rarefied gas dynamics and gas-liquid flows, as well as to addressing practical problems of modern astronautics.

Keywords: jets of spacecraft attitude control thrusters, modeling in vacuum chambers, plume backflow, gasdynamic protective devices, full-scale on-orbit experiments

For citation: Yarygin V. N., Prikhodko V. G., Yarygin I. V. Experimental modeling of jets from low-thrust liquid-propellant rocket engines. Aerospace Engineering and Technology. 2026. Vol. 4, no. 1, pp. 51–65. (In Russ.) https://doi.org/10.52467/2949-401X-2026-4-1-51-65; https://elibrary.ru/SHVDFG

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