Numerical Analysis Of The Relationship Between Gas Filtration Model Parameters In Underground Gas Storage Nazariy Lopuh, Myroslav Prytula, Zoia Prytula, Yaroslav Pyanylo, Nazar Prytula, Olga Khymko Proceedings International Conference on Advanced Computer Information Technologies Acit, 2025 The paper presents a numerical analysis of the relationship between the key parameters of a gas filtration model in an underground gas storage (UGS) system, specifically the permeability and porosity, and the orders of fractional derivatives of gas pressure with respect to time and space. The study is based on a generalized filtration model that accounts for anomalous (subdiffusive) effects typical of fractured and heterogeneous reservoirs. The orders of the fractional derivatives (α—for time, β—for space) are treated as variable parameters, allowing the identification of their dependencies on classical filtration characteristics of the medium. The Grunwald method was employed to approximate the fractional derivatives, enabling stable numerical simulations based on both experimental and synthetic data.
Methods of Analysis of Integrity of Gas Facilities Yaroslav Pyanylo, Nazar Prytula, Nazariy Lopuh, Myroslav Prytula, Zoia Prytula, Olga Khymko Proceedings International Conference on Advanced Computer Information Technologies Acit, 2025 The object of the study is the integrity of underground gas storage facilities (UGS) and gas transmission system (GTS). The problems of analysing the consequences of depressurization of gas facilities were solved. Real examples of violation of the integrity of facilities were considered. An analysis of the existing mathematical analytical apparatus for calculating the volumes of gas leaks was provided. The use of such an apparatus does not always provide a correct analysis of the results of depressurization of gas facilities. Numerical methods for studying the integrity of gas networks of complex structure by modelling were proposed. The results obtained confirm the effectiveness of mathematical methods for practical use.
Optimal Planning of Operation Modes of Gas Transmission Systems Yaroslav Pyanylo, Nazar Prytula, Olga Khymko, Myroslav Prytula, Zoia Prytula Proceedings International Conference on Advanced Computer Information Technologies Acit, 2024 The object of the study is the gas transmission system (GTS) and underground gas storage facilities (UGSF). The problem to be solved is the planning of optimal modes of their operation. In the process of studying the operation of GTS and UGS, a significant potential for their joint optimization was revealed. The factors affecting the optimal operation of the GTS and UGS and the problems of implementing optimal modes are analyzed. The developed and implemented combinatorial optimization methods of minimum complexity ensured a quick calculation of optimal modes according to the energy and mode stability criteria. The developed software has been tested and is used by dispatch services as a decision support system.
REVEALING PATTERNS IN THE INFLUENCE OF VARIABLE PERMEABILITY OF WELL BOTTOMHOLE ZONES ON THE OPERATIONAL MODES OF UNDERGROUND GAS STORAGE FACILITIES Myroslav Prytula, Nazar Prytula, Yaroslav Pyanylo, Zoia Prytula, Olga Khymko Eastern European Journal of Enterprise Technologies, 2023 The object of this study is underground gas storage facilities (UGSF). The main problem being solved is to ensure effective management of the operation process of underground gas storage facilities (UGSF) at operational and forecast time intervals. One of the main factors that affect the operating modes of UGSF is significantly non-stationary filtration processes that take place in the bottomhole zones of wells. The complexity of assessing the multifactorial impact on depression/repression around the wells affects both the speed and accuracy of calculating the mode parameters of UGSF operation. Analysis of the results of well studies revealed a significant area of uncertainty in the calculation of the filtration resistance coefficients of their bottomhole zones. A satisfactory accuracy of the result in the expected time was achieved by building a model of integrated consideration of the influence of the parameters of all the bottomhole zones of the wells on the mode of UGSF operation. It turned out that the integrated consideration of the impact on the parameters of the bottomhole zones of the wells neutralized the effect of significant changes in the filtration resistance coefficients of the wells and ensured a sufficient speed of calculation of UGSF operation modes. Simultaneous simulation of ten operating UGSFs under the peak mode of withdrawal the entire available volume of active gas takes no more than six minutes. The speed of simulation of filtration processes in the bottomhole zones of wells ensured finding the best of them according to one or another criterion of operation mode quality. As a result of the research, a model was built and implemented by software, which was tested under real operating conditions and provides optimal planning of UGSF operating modes for given time intervals. Its use is an effective tool for the operational calculation of current modes and technical capacity of UGSF for a given pressure distribution in the system of main gas pipelines. The performance of the constructed mathematical methods has been confirmed by the results of numerical experiments
Hydrodynamic Studies of Underground Gas Storages Yaroslav Pyanylo, Zoia Prytula, Myroslav Prytula, Olha Hymko, Nazar Prytula, Halyna Pyanylo Proceedings International Conference on Advanced Computer Information Technologies Acit, 2023 Problems of research of underground gas storage (UGS) wells are given. The analysis of the results of well research is carried out and the constant variability of filtration resistance coefficients of bottomhole zones of wells is substantiated. Studies of the influence of bottomhole pressures of wells on the calculated pressure at gas gathering stations (GGS) of underground storage facilities have been carried out. It was found that the calculated filtration resistance coefficients do not allow to calculate the pressures at the gas gathering stations of the underground storage plant with sufficient accuracy. The magnitude of the discrepancy between the measured and calculated pressures on the GGS varies depending on the flow rate and operating time of wells. It is established that the calculation of depression (repression) of pressure in the bottomhole zones of wells in non-stationary conditions of their operation gives underestimated results.
PLANNING OPTIMAL OPERATING MODES OF UNDERGROUND GAS STORAGE FACILITIES AS PART OF THE GAS TRANSMISSION SYSTEM Myroslav Prytula, Nazar Prytula, Yaroslav Pyanylo, Zoia Prytula, Olga Khymko Eastern European Journal of Enterprise Technologies, 2022 The object of this study is underground gas storage facilities (UGSF) as part of the gas transmission system (GTS), in the process of joint operation of which a significant synergistic effect is achieved. The problem under consideration is to ensure the joint effective operation of the integrated UGSF and GTS complex as a single thermal-hydraulic one. A method of daily calculation of the maximum productivity of underground gas storage facilities has been devised. The optimization potential of UGSF operating modes has been studied. It is shown to range within 11‒20 %. The problems of planning the operation of UGSF have been stated and solved both under gas pumping modes and gas withdrawal modes. An algorithm for planning gas withdrawal modes at intervals of peak-free UGSF operation been developed. The achieved computational complexity of problem-solving algorithms is in the range of 2‒10 seconds. The problem of combining simultaneous operation of UGSF under an optimal mode for fuel gas and ensuring the necessary peak operation of UGSF at projected time intervals has also been considered. The joint UGSF performance was calculated at the projected time intervals according to the established criteria. At the same time, thermal-hydraulic coordination of UGSF operating modes with the operation of the GTS main gas pipeline system with which they are integrated was ensured. The problem was solved as a result of the implementation of a universal approach to the construction of functional models of complex systems – a single information support, the representation of the structure of the system in terms of graphs, the statement of proper mathematical problems, the development of methods for guaranteed convergence of systems with different mathematical representations of equations, the development of computational algorithms for combinatorial optimization of minimum complexity processes with discrete and irregular influences on their behavior
