Novikov L.A., Bokyi A.B. Calculation of degassing networks taking into account the accumulation of the liquid phase

Geoteh. meh. 2019, 148, 110-118

https://doi.org/10.1051/e3sconf/201910900063

CALCULATION OF DEGASSING NETWORKS TAKING INTO ACCOUNT THE ACCUMULATION OF THE LIQUID PHASE

1NovikovL.A., 2BokyiA.B.

11Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine, 2LLC "DzhiI Ukraine"

UDC [622.817.47:533.6]:001.24                      

Language: English

Abstract. The article the issue of accounting for accumulations of liquid in the degassing network and humidity of the gas mixture during gas-dynamic calculations is considered. The estimated scheme of the degassing network of the mine is presented. The shape of the accumulation liquid in the cross section of a degassing pipeline is considered. Formulas are obtained for determining the perimeter of the passage section of the pipeline in the place of accumulation of the liquid phase, the area and hydraulic diameter of the passage section of the pipeline, the cross-sectional area of the segmental volume of the liquid accumulation, Reynolds numbers. Relations are presented for the coefficient of resistance to friction and the coefficient of resistance to interfacial friction for places of localization of the liquid phase. It is shown that the interaction of the gas mixture with the free surface of the liquid accumulation leads to the appearance of wave perturbations of the liquid. These disturbances are considered as an analogue of the roughness of the contaminated surface of the pipeline. In this case, the interaction of the gas mixture with the free surface of the liquid can be characterized by a coefficient of resistance to interfacial friction. Relations are presented for the absolute pressure, flow rate and density of the gas mixture in the degassing pipeline. Numerical methods for calculating gas pipelines are considered. An analysis of the methods used showed that the main errors in the calculation of gas-dynamic parameters are most characteristic for local resistances (including accumulations of liquids), as well as for joints of pipelines of various diameters. The results of calculating the friction and interfacial friction loses coefficients, the gas mixture consumption and the consumption characteristics of degassing pipelines are presented. The results showed that the values of the coefficient of loss interfacial friction at the place of accumulation of fluid can exceed the value of the Darcy coefficient. It was established that in places of accumulations of the liquid phase, additional losses of the absolute pressure of the gas mixture occur, which leads to a decrease in its flow rate. In this case, fluctuations in the consumption of gas mixture are observed, which are caused by the periodic formation of wave disturbances of the liquid.

Keywords: degassing network, accumulation of liquid, degassing pipeline, gas mixture.

References

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2. Krivoshchekov, V.I., Novikov, L.A. (2016), “Regularities of change in pressure loss in a low pressure pipeline”,                      Zbahachennya korysnykh kopalyn, no. 64, pp. 26-29.

3. Mukha, О.А. and Puhach, І.І. (2009), Rozrahunok parametriv degazatsiynih system [Calculation of degassing system parameters], National Mining University, Dnipropetrovsk, Ukraine.

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5. Novikov, L.A. (2015), “Gas dynamics flooded areas degassing pipeline and methods of calculation of parameters”,                  Geo-Technical Mechanics, no. 120, pp. 234-243.

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About the authors

Novikov Leonid Andriiovych,Candidate of Technical Sciences (Ph.D.), Junior Researcher in Department  of Mineral Mining at Great Depths, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine(IGTM, NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

Bokyi Anatolii Borysovych,Candidate of Technical Sciences (Ph.D.), LLC "DzhiI Ukraine", Kiev, Ukraine.