Conceptual model and analysis of the efficiency and cost effectiveness of an ideal reciprocating compressor with an active liquid piston for isothermal gas compression

After analyzing existing methods and designs currently used for efficient gas compression, it was found that using a liquid layer above a mechanical piston solves not only the cooling problem but also seals the working chamber and reduces dead volume to zero. To improve the efficiency of such a compressor, it is proposed to use an active (controlled) piston, which allows for changes in the compressor’s working chamber volume according to a law similar to that of isothermal gas compression. This paper develops a conceptual model of a reciprocating compressor with a controlled liquid piston within the accepted assumptions and describes the dynamics of changes in the liquid layer above the piston. After developing the conceptual model and analyzing the dynamics of fluid movement in the working chamber, it is shown that in an ideal piston compressor with a liquid active piston, the delivery ratio can be greater than 1. Using the efficiency loss separation method, a relationship is established between the relative dead volume and the heating and throttling factors to ensure a delivery ratio of 1 or greater. Based on the disclosure of the physical characteristics of the gas compression process, as well as the dynamics of fluid movement in the suction and injection processes, an expression for determining the indicated isothermal efficiency was obtained.
EDN: LPZWXL, https://elibrary/lpzwxl

References

[1] Shcherba V.E., Shalai V.V., Kostyukov V.N. et al. A mathematical model of the working processes of a hybrid power displacement piston machine with profiled groove seal. Chem. Petrol. Eng., 2018, vol. 54, no. 5–6, pp. 335–344, doi: https://doi.org/10.1007/s10556-018-0484-1

[2] Shcherba V.E., Bolshtyanskii A.P., Kaigorodov S.Yu. et al. Benefits of integrating displacement pumps and compressors. Russ. Engin. Res., 2016, vol. 36, no. 3, pp. 174–178, doi: https://doi.org/10.3103/S1068798X1603014X

[3] Bazhenov A.M., Shcherba V.E., Shalai V.V. et al. Modeling the operation of bulk-action hybrid piston power systems. Russ. Engin. Res., 2019, vol. 39, no. 5, pp. 377–382, doi: https://doi.org/10.3103/S1068798X19050046

[4] Shcherba V.E., Nosov E.Yu., Tegzhanov A.S. et al. An experimental study of a crossheadless piston hybrid power positive displacement machine with intensive cooling of the compressed gas. Izvestiya vysshikh uchebnykh zavedeniy. Mashinostroenie [BMSTU Journal of Mechanical Engineering], 2019, no. 10, pp. 78–85, doi: https://doi.org/10.18698/0536-1044-2019-10-78-85 (in Russ.).

[5] Shcherba V.E., Shalai V.V., Pustovoy N.V. et al. On profiling of the working cavity of the second stage in a hybrid piston volumetric power machine. Chem. Petrol. Eng., 2020, vol. 56, no. 1–2, pp. 125–136, doi: https://doi.org/10.1007/s10556-020-00749-0

[6] Shcherba V.E., Aver’yanov G.S., Pavlyuchenko E.A. et al. Viscous incompressible fluid flow in a positive displacement two-stage piston hybrid energy-generating machine having a gas cap. Chem. Petrol. Eng., 2021, vol. 56, no. 11–12, pp. 988–997, doi: https://doi.org/10.1007/s10556-021-00873-5

[7] Shcherba V.E., Shalay V.V., Nosov E.Yu. et al. Development and research of crosshead-free piston hybrid power machine. Machines, 2021, vol. 9, no. 2, art. 32, doi: https://doi.org/10.3390/machines9020032

[8] Shcherba V.E., Pavlyuchenko E.A., Nosov E.Yu. et al. Approximation of the compression process to isothermal in a reciprocating compressor with a liquid piston. Appl. Therm. Eng., 2022, vol. 207, art. 118151, doi: https://doi.org/10.1016/j.applthermaleng.2022.118151

[9] Shcherba V.E., Tegzhanov A.S., Nosov E.Yu. et al. Comparative analysis of mass-dimensional a comparative analysis of mass-dimensional indicators of crossheadless and crosshead piston hybrid energy positive displacement machines. Izvestiya vysshikh uchebnykh zavedeniy. Mashinostroenie [BMSTU Journal of Mechanical Engineering], 2019, no. 9, pp. 88–95, doi: https://doi.org/10.18698/0536-1044-2019-9-88-95 (in Russ.).

[10] Shcherba V.E., Shalai V.V., Tegzhanov A.S. et al. Generalized comparative analysis of crosshead-free and crosshead schemes of piston hybrid power machines. J. Mech. Sci. Technol., 2020, vol. 34, no. 12, pp. 5093–5107, doi: https://doi.org/10.1007/s12206-020-1113-4

[11] Nosov E.Yu., Shcherba V.E., Kuzhbanov A.K. et al. Development of a prototype of the piston hybrid energy machine of volumetric action with the regenerative heat exchange and a bench for its study. Izvestiya vysshikh uchebnykh zavedeniy. Mashinostroenie [BMSTU Journal of Mechanical Engineering], 2025, no. 2, pp. 90–100. EDN: CMEQDO (in Russ.).

[12] Shcherba V.E., Khait A., Nosov E.Yu. et al. Numerical analysis of unsteady heat transfer in the chamber in the piston hybrid compressor with regenerative heat exchange. Machines, 2023, vol. 11, no. 3, art. 363, doi: https://doi.org/10.3390/machines11030363

[13] Shcherba V.E. Method for estimating the operating time in the compressor mode of a reciprocating hybrid power machine with regenerative heat exchange. Izvestiya vysshikh uchebnykh zavedeniy. Mashinostroenie [BMSTU Journal of Mechanical Engineering], 2022, no. 10, pp. 96–102, doi: https://doi.org/10.18698/0536-1044-2022-10-96-102 (in Russ.).

[14] Shcherba V., Khait A. Comparative analysis of the regenerative and recuperative cooling of reciprocating compressors. Mech. Based Des. Struct. Mach., 2025, vol. 53, no. 12, pp. 8004–8023, doi: https://doi.org/10.1080/15397734.2025.2505194

[15] Guo Y., Wang T., Liu X. et al. Mathematical modelling and design of the ionic liquid compressor for the hydrogen refuelling station. Int. J. Energy Res., 2022, vol. 46, no. 13, pp. 19123–19137, doi: https://doi.org/10.1002/er.8224

[16] Zhou H., Dong P., Zhu S. et al. Design and theoretical analysis of a liquid piston hydrogen compressor. J. Energy Storage, 2021, vol. 41, art. 102861, doi: https://doi.org/10.1016/j.est.2021.102861

[17] Van de Ven J.D., Li P.Y. Liquid piston gas compression. Appl. Energy, 2009, vol. 86, no. 10, pp. 2183–2191, doi: https://doi.org/10.1016/j.apenergy.2008.12.001

[18] Patil V.C., Ro P.I. Experimental study of heat transfer enhancement in liquid piston compressor using aqueous foam. Appl. Therm. Eng., 2020, vol. 164, art. 114441, doi: https://doi.org/10.1016/j.applthermaleng.2019.114441

[19] Li C., Wang H., He X. et al. Experimental and thermodynamic investigation on isothermal performance of large-scaled liquid piston. Energy?2022, vol. 249?art. 123731, doi: https://doi.org/10.1016/j.energy.2022.123731

[20] Plastinin P.I. Porshnevye kompressory. T. 1. Teoriya i raschet [Piston compressors. Vol. 1. Theory and calculation]. Moscow, KolosS Publ., 2006. 456 p. (In Russ.).