FEATURES OF THE MATHEMATICAL SIMULATION OF DYNAMIC PROCESSES IN THE RECONFIGURABLE PROPELLANT FEED HYDRAULIC SYSTEM OF LIQUID-PROPELLANT ROCKET ENGINES

Abstract

DOI: https://doi.org/10.15407/itm2026.01.023

Hydraulic pipeline systems in liquid-propellant rocket engines (LPREs) are numerous and diverse. In staged-combustion LPREs, use is made of reconfigurable hydraulic systems, in which the propellant component flow directions change during an engine start-up. A reliable engine start-up requires a smooth transition from the start-up propellant supply to the main propellant supply. The objective of this study is to develop an approach to the mathematical simulation of dynamic processes in a branched reconfigurable hydraulic feed system. A methodological framework for modeling dynamic processes in such systems is proposed. It involves determining the frequency responses of several configurations of a hydraulic system realized at different stages of its operation as a distributed-parameter system. The next step is the construction of a lumped-parameter mathematical model with fluid motion and continuity equations in lumped parameters. Lumped compliances are typically introduced in the hydraulic network model at pipeline junctions. Their number and values are selected so that the frequency responses of the distributed- and lumped-parameter models for each hydraulic system configuration may be in agreement within a prescribed accuracy. To demonstrate the proposed approach, a test reconfigurable hydraulic system is considered. Two configurations of the hydraulic system are set off: from the start-up tank to the gas generator and from the pump outlet to the gas generator. For both configurations, frequency responses of the corresponding distributed-parameter systems are determined. A lumped-parameter mathematical model of dynamic processes in the hydraulic system under analysis is developed. The values of the lumped compliances at the network nodes are identified such that the frequency responses of the distributed- and lumped-parameter models are in satisfactory agreement. It is shown that the values of the lumped compliances remain practically unchanged for different hydraulic system configurations, boundary conditions, or propellant mixture ratios in the gas generator.

REFERENCES

1. Thorley A. R. D. Fluid Transients in Pipeline Systems. London: City University, 2004. 304 pp.

2. Su H., Sheng L., Zhao Sh., Lu Ch., Zhu R., Chen Y., Fu Q. Water hammer characteristics and component fatigue analysis of the essential service water system in nuclear power plants. Processes. 2023. V. 11. Iss. 12. 3305.
https://doi.org/10.3390/pr11123305

3. Quan L., Gao J., Guo C., Fu C. Analysis of water hammer and pipeline vibration characteristics of submarine local hydraulic system. J. Mar. Sci. Eng. 2023. V.11, Iss.10. 1885.
https://doi.org/10.3390/jmse11101885

4. Pylypenko O. V., Dolgopolov S. I., Nikolayev O. D., Khoriak N. V. Mathematical modeling of the transient processes in propulsion system of the upper stage of the Cyclone-4M launch vehicle. Science and Innovation 2024. V. 20. No.1. Pp. 49-67.

5. Das D., Padmanabhan P. Study of pressure surge during priming phase of start transient in an initially unprimed pump-fed liquid rocket engine. Propulsion and Power Research. 2022. V. 11. No. 3. Pp. 353-375.
https://doi.org/10.1016/j.jppr.2022.07.003

6. Das D., Waghmare Sh., Padmanabhan P., Kumaresan V., Sudhakar D. P. Control of opening duration in a pneumatically operated valve with two-fluid combination and quadratic damping. Journal of Engineering and Applied Science. 2023. V. 70. 41.
https://doi.org/10.1186/s44147-023-00207-7

7. Cherniavskyi O. S., Dolgopolov S. I., Shevchenko S. A. Modeling of a check valve operation in the reconfigurable hydraulic feed system of a liquid rocket engine. Teh. Meh. 2025. No. 4. Pp. 19-30.
https://doi.org/10.15407/itm2025.04.019

8. Dolgopolov S. I., Nikolayev O. D., Khoriak N. V. Dynamic interaction between clustered liquid propellant rocket engines under their asynchronous start-ups. Propuls. Power Res. 2021. V. 10. Iss. 4. Pp. 347-359.
https://doi.org/10.1016/j.jppr.2021.12.001

9. Li H., Guo Y., Xu K., Yan X. Simulation of characteristics of staged combustion cycle rocket engine and control valve based on AMESim/Simulink. Journal of Aerospace Power. 2024. V. 39. Iss. 1. 8 pp. https://doi.org/10.13224/j.cnki.jasp.20210401 (In Chinese).

10. Su Q., Wang J., Yan M., Sun Z., Huang W., Zha B. Dynamic characteristics of LOX/Kerosene variable thrust liquid rocket engine test system based on general modular simulation method. International Journal of Aerospace Engineering. 2022. 14 pp. https://doi.org/10.1155/2022/2171471
https://doi.org/10.1155/2022/2171471

11. Huang P., Yu H., Wang T. A study using optimized LSSVR for real-time fault detection of liquid rocket engine. Processes. 2022. V.10. Iss. 8. 1643.
https://doi.org/10.3390/pr10081643

12. Dong L., Nie W., Li G. Modeling, simulation and experimental study of squeeze engine system. Journal of Physics: Conference Series. 2022. V. 2288. 012003.
https://doi.org/10.1088/1742-6596/2228/1/012003

13. Naderi M., Karimi H., Guozhu L. Modeling the effect of reusability on the performance of an existing LPRE. Acta Astronautica. 2021. V. 181. Iss. 4. Pp. 201-216.
https://doi.org/10.1016/j.actaastro.2020.12.001

14. Pérez-Roca S., Marzat J., Piet-Lahanier H., Langlois N., Galeotta M., Farago F., Le Gonidec S. Model-based robust transient control of reusable liquid-propellant rocket engines. IEEE Transactions on Aerospace and Electronic Systems. 2021. V. 57. Iss.1. Pp. 129-144.
https://doi.org/10.1109/TAES.2020.3010668

15. Degtyarev A. V., Shulga V. A., Zhivotov A. I., Dibrivny A. V. The development of lox-kerosene liquid rocket engines family for perspective launch vehicles of Yuzhnoye SDO based on proven technologies. Aerospace Technic and Technology. 2013. No. 1. Pp. 44-50. (In Russian).

16. Prokopchuk А. А., Shulga V. А. The advanced liquid rocket engine line of SDO "Yuzhnoye" for the creation of new families of launch vehicles. Kosm Nauka Technol. 2015. V. 21, No. 5. Pp. 28-35. (In Russian).
https://doi.org/10.15407/knit2015.05.028

17. Prokopchuk O. O., Shulga V. A. New and advanced liquid rocket engines of the Yuzhnoye SDO. Kosm. Teh. Raket. Vooruž. 2024. No 1 (121). Pp. 9-18. ( in Ukrainian).
https://doi.org/10.33136/stma2024.01.009

18. Pylypenko V. V., Zadontsev V. A., Natanzon M. S. Cavitation Oscillations and Dynamics of Hydraulic Systems. Moscow: Mashinostroyeniye, 1977. 352 p. (In Russian).

19. Fox J. A. Hydraulic Analysis of Unsteady Flow in Pipe. London: Red Globe Press, 1977. 216 pp.
https://doi.org/10.1007/978-1-349-02790-3

20. Pylypenko O., Dolgopolov S., Nikolayev O., Khoriak N., Kvasha Yu., Bashliy I. Determination of the thrust spread in the Cyclone-4M first stage multi-engine propulsion system during its start. Science and Innovation. 2022. V. 18. No. 6. Pp. 97-112.

21. Dolgopolov S., Cherniavskyi O., Shevchenko S. Mathematical modeling of dynamic processes in the branched reconfigurable fuel feed system of a liquid‑propellant rocket engine. CEAS Space Journal. 2025. 14 pp.
https://doi.org/10.1007/s12567-025-00691-y

22. Shevyakov A. A., Kalnin V. M., Naumenkova M. V., Dyatlov V. G. Theory of Automatic Control of Rocket Engines. Moscow: Mashinostroyeniye, 1978. 288 pp. (in Russian).

23. Belyaev E. N., Chervakov V. V. Mathematical Modeling of LPRE. Moscow: MAI-PRINT Publ., 2009. 280 рp. (In Russian).

24. Yan Z., Peng X., Cheng Y., Wu J. Modeling and simulation of system dynamics for spacecraft propulsion system. Applied Mechanics and Materials. 2012. Vs. 229-231. Pp. 2112-2116.
https://doi.org/10.4028/www.scientific.net/AMM.229-231.2112

25. Altshul A. D. Hydraulic Resistances. Moscow: Nedra, 1970. 216 pp. (In Russian).