Дослідження витоку газу з трубопроводу

There are presented the research results of gas leak from the pipeline under pressure through a small hole in a thin wall. The analysis of equations of gas flow energy in the process of gas leak allows making under certain assumptions a formula for the mass flow of gas through a small hole in a wall. However, the experience shows that the assumptions significantly distort the actual state of physical process that ultimately leads to uncertainty in the obtained results. In this regard, there are made a number of analytical and experimental studies to assess the adequacy of theoretical statements with restrictions and the actual results of experiments. The result of the research is an adjustment for the theoretical dependence for the mass flow rate of gas. which Hows through a small hole from the tank. There is also showed the dependence of the adjustment on the pressure and temperature of gas in the tank

Нестаціонарні процеси у нафтопродуктопроводі при використанні протитурбулентних присадок

The problem of a non-stationary flow of petroleum products by the pipeline in the process of its displacement by anti-turbulence additives is studied in the article. There is made a mathematical model of motion of a contact for two liquid media with different hydraulic characteristics in the pipeline. The model implementation allows predicting the type of motion of the moving boundary, pressure distribution and flow of petroleum products during the process of non-stationary displacement. It is determined that oscillation of parameters in time is negligible, and it allows recommending the quasistationary motion models for predictive calculations

Numerical simulation of the stress state of an erosion-worn tee of the main gas pipeline

Purpose: To investigate the strength of tees with regard to their erosion wear, it is necessary to consider the complex three-dimensional geometric shape of the erosion worn inner surface of the tee. In addition, the study of the strength of the erosion worn tees of the main gas pipelines is complicated by the occurrence of additional stresses caused by changes in the direction of movement of the gas stream, resulting in an uneven pressure distribution in the inner cavity of the tee, and the temperature difference in its walls. Design/methodology/approach: Methodology for complex numerical three-dimensional simulation of the stressed state of tees of the main gas pipelines, taking into account the gas-dynamic processes that occur in the places of these defects, erosion wear of the tee wall, temperature difference in the tee walls. Findings: The acceptable parameters of erosion defects of tees of gas pipelines, and residual life of tees with erosion defects of the wall should be determined. Research limitations/implications: The developed model does not take into account internal corrosion and corrosion products as an additional erosion factor. Further studies plan to develop a model of corrosion-erosion wear of pipeline elements. Practical implications: The developed technique allows determining the location of erosion defects, estimating the strength and determining the residual life of tees with erosion wear of the wall in order to ensure their reliability, to rank such defects according to the degree of danger, to determine which of them are critical and need an immediate repair. Originality/value: Based on the gas-dynamic processes occurring in the internal cavity of the main gas pipelines’ tees, the complex three-dimensional geometric form of wall erosion defects, and temperature difference, the technique of three-dimensional simulation of stress state of the main gas pipelines’ tees is develope