Influence of propellant leakage from pump area into turbine area on turbo-pump operation stability

1Andriievskyi, MV, 2Mitikov, Yu.O
1Propulsion Systems Department of the Ukrainian branch of Skyrora Ltd, Edinburgh, UK; Oles Honchar National University of Dnipro, Dnipro, Ukraine
2Oles Honchar National University of Dnipro, Dnipro, Ukraine
Space Sci. & Technol. 2021, 27 ;(1):97-102
https://doi.org/10.15407/knit2021.01.097
Publication Language: English
Abstract: 
There is an increasing trend to liquid-propellant rocket engines which run on eco-friendly storable propellant. This trend is mostly dictated by the refusal to use traditional toxic storable propellant in many countries. The most widespread eco-friendly storable propellant is hydrogen peroxide with kerosene. Though, this propellant has a lower specific impulse in comparison with traditional liquid oxygen with kerosene. To compensate the loss of specific impulse, there is a reason to design a staged combustion engine. Evidently, the turbopump is the most complicated system in the staged combustion propulsion system. This fact makes research devoted to turbo-pumps a top priority. The paper aims to determine the influence of propellant leakage from the pump area into the turbine area and create recommendations which would allow organizing the stable operation of turbopump. As a result of turbopump staged combustion cycle testing, a conclusion had been made that leakage, which opens during the test, significantly influences the stability of turbopump operation. Depending on the amount of leakage, the turbine generated power drop was between 20 and 45%, which led to a decrease in rotation speed and outlet pressure of the pump. During the R&D process, a way of leakage influence elimination had been offered. Formulated recommendations may be used during the design process of the turbopump for staged combustion liquid propulsion systems.
Keywords: hydrogen peroxide, leakage, mechanical sealing, operational stability, rocket engine, turbo-pump
References: 
1. Anderson W. E., Butler K., Crocket D., Lewis T., McNeal C. (2000). Peroxide propulsion at the turn of the century. 4th International Symposium on Liquid Propulsion (3 March 2000), Heilbronn, Germany, 59 p.
2. Andriievskyi M. (2019). Peculiarities of start transience of the rocket engine which runs on eco-friendly storable propellant. Vestnik Dvigatelestroeniya, No. 1, 29—34 [in Russian].
3. Andriievskyi M., Mitikov Y., Shamrovskyi D. (2018). Control Peculiarities of Rocket Engine Which Runs on Ecologically friendly Storable Propellant. Vestnik Dvigatelestroeniya, No. 1, 16—21 [in Russian].
4. de Selding Peter B. (2016). SSTL Developing Non-toxic Thruster ahead of Possible European Hydrazine Ban. Paris: Space News.
5. Geymberger Yu. O., Gorbenko G. A., Shementov A. M. (2009). Design and Development of Liquid Propulsion Engines Feeding Systems. RVV DNU, 96 p.
6. Huzel D. K., Huang D. H. (1967). Design of Liquid Propellant Rocket Engines. Houston: National Aerospace and Space Administration, 461 p.
7. Ivanov Ya. N., Badun O. P., Deshevyih S. A., Ivchenko L. F. (2018). Turbo-Pumps of Rocket Engines designed in Yuzhnoye design office. Kosmicheskaya tehnika. Raketnoe vooruzhenie, No. 2, 26—33 [in Russian].
8. Ivchenko L. F., Deshevyih S. A., Maksimchuk R. F. (2012). Design experience of RD 861K autonomous turbine. Aviatsionno-kosmicheskaya tehnika i tehnologiya, No. 9, 174—179 [in Russian].