Design and operational features of rocket engines turbopumps turbine-pump intershaft seal systems. Part I. Separation of the same reaction components

Liquid-propellant rocket engines remain the dominant propulsion technology for orbital launch vehicles. Their performance is fundamentally dependent on turbopump assemblies to pressurize and deliver propellants to all engine systems. This article addresses a critical turbopump assemblies design element: the turbine-pump intershaft sealing systems. The integrity of these seals is paramount to overall feed system reliability and efficiency. Leakage across this barrier carries severe consequences. Flow of pump fluid into the turbine volute degrades turbine efficiency and can induce steep thermal gradients, resulting in excessive rotor disk stresses. Conversely, ingestion of hot turbine drive gases into the pump end compromises the turbine bearing environment and risks pump cavitation. Effective seal design necessitates a systems-level approach, accounting for transient engine operating conditions and manifold pressures. Consequently, seal configuration analysis and selection must be an integral focus during preliminary design reviews to ensure engine performance and operational margins.
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References

[1] Gakhun G.G., ed. Konstruktsiya i proektirovanie zhidkostnykh raketnykh dvigateley [Design and engineering of liquid rocket engines]. Moscow, Mashinostroenie Publ., 1989. 424 p. (In Russ.).

[2] David H., Huang D., Huzel K. Modern engineering for design of liquid-propellant rocket engines. AIAA, 1992. 426 p.

[3] Ivanov A.V., Belousov A.I., Dmitrenko A.I. Turbonasosnye agregaty kislorodno-vodorodnykh ZhRD [Turbo-pump units for oxygen-hydrogen rocket engines]. Voronezh, VGTU Publ., 2011. 284 p. (In Russ.).

[4] Golubev A.I., Kondakov L.A., eds. Uplotneniya i uplotnitelnaya tekhnika [Seals and sealing technology]. Moscow, Mashinostroenie Publ., 1994. 445 p. (In Russ.).

[5] Kanalin Yu.I., Chernyshova I.A. Ensuring the performance characteristics of TNA turbines when they are used as part of a liquid rocket engine. Trudy NPO Energomash, 2015, no. 32, pp. 237–262. (In Russ.).

[6] Zaytsev N.A., Kuchin A.P., Momotov V.I. et al. Opyt vnedreniya meropriyatiy po povysheniyu nadezhnosti TNA seriyno izgotavlivaemykh ZhRD [Experience in implementing measures to improve the reliability of serial-produced liquid-propellant rocket engines]. V: Nauchno-tekhnicheskiy yubileynyy sbornik KB khimavtomatiki. T. 1 [In: Scientific and technical jubilee collection of the chemical automation design bureau. Vol. 1]. Voronezh, Kvarta Publ., 2001, pp. 348–356. (In Russ.).

[7] Melnik V.A. Tortsovye uplotneniya valov [Shaft mechanical seals]. Moscow, Mashinostroenie Publ., 2008. 320 p. (In Russ.).

[8] Demyanenko Y., Dmitrenko A., Ivanov A. et al. Turbopumps for gas generator and staged combustion cycle rocket engines. 41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2005, art. 3946, doi: https://doi.org/10.2514/6.2005-3946

[9] Matveev N.K., Semenov A.A. Ustroystvo dvigatelya RD-119 [RD-119 engine design]. Sankt-Peterburg, BGTU Publ., 2020. 47 p. (In Russ.).

[10] Pempie P. Tribology on rocket engine. STLE’s 2005 Annual Meeting, 2005. URL: https://www.researchgate.net/publication/288828569_Tribology_on_Rocket_Engine (accessed: 15.02.2026).

[11] J-2 engine fact sheet. URL: https://www.chrispennello.com/j2/J-2%20Engine%20Fact%20Sheet.pdf (accessed: 15.02.2026).

[12] Merkle C.L., Brown J.R., McCarty J.P. et al. JTEC panel report on space and transatmospheric propulsion technology. NASA-CR-187670. Technical report 19910007821. NTIS, 1990. 235 p.

[13] Space Transportation System Training Data. URL: https://lpre.de/p_and_w/SSME/SSME_PRESENTATION.pdf (дата обращения: 18.08.2026).

[14] Gibson H., Thom R., Moore C. et al. History of space shuttle main engine turbopump bearing testing at the Marshall Space Flight Center. URL: https://ntrs.nasa.gov/search.jsp?R=20100023061 (accessed: 15.02.2026).

[15] Fusaro R., Ferretto D., Vercella V. et al. A methodology for preliminary sizing of a Thermal and Energy Management System for a hypersonic vehicle. ICAS, 2018. URL: https://iris.polito.it/retrieve/handle/11583/2837928/379529/ICAS2018_0429_paper.pdf (accessed: 15.02.2026).

[16] Ivanov A.V., Demyanenko Yu.V., Dmitrenko A.I. et al. [Units of the oxygen-hydrogen engine power supply RD0146]. V: Nauchno-tekhnicheskiy yubileynyy sbornik KB khimavtomatiki. T. 2 [In: Scientific and technical anniversary collection of KB of chemical automation. Vol. 2]. Voronezh, Kvarta Publ., 2012, pp. 169–176. (In Russ.).

[17] Ivanov A.V., Dmitrenko A.I., Kravchenko A.G. Turbonasosnyy agregat [Turbopump unit]. Patent RU 2533595. Appl. 01.10.2013, publ. 20.11.2014. (In Russ.).

[18] Kraev M.V., Ovsyannikov B.V., Shapiro A.S. Gidrodinamicheskie radialnye uplotneniya vysokooborotnykh valov [Hydrodynamic radial seals for high-speed shafts]. Moscow, Mashinostroenie Publ., 1976. 104 p. (In Russ.).

[19] Katorgin B.I., Semenov B.I., Chvanov V.K. et al. Development and introduction of the powerful RD180 main engine into the global market. Trudy NPO Energomash imeni akademika V.P. Glushko, 2003, no. 21, pp. 150–171.

[20] Ivanov A.V. Proektirovanie uplotneniy protochnoy chasti TNA ZhRD [Design of the flow part seals of the liquid rocket engine thrust vector assembly]. Moscow, ID Akademii Zhukovskogo Publ., 2024. 264 p. (In Russ.).