PSEUDO STABLE STEAM-WATER FLOW IN PRODUCTIVE GEOTHERMAL WELL
Currently, world geothermal power generation is developing, in general, in a fair competition with other energy areas. The new conditions of competition and the high cost of drilling cause the urgency of the issues related to improving the efficiency of the use of wells. In the present article explores the mechanism that ensures the stability of the operation mode of steam-water wells. The major cause of instability is considered to be a mismatch between the feed capacity of the aquifer and well bandwidth. Matching characteristics feed aquifer and well carried out by analyzing the graphs of the dependence of flow-rate from bottomhole pressure. For example, the well corresponding to the average performance Pauzhetka field, noted the possibility of finding the point of harmonization at the descending branch of the characteristics of the well. For flow conditions at this point to the dominance of the gravitational component of the pressure drop the mechanism of instability is revealed and the corresponding stability criterion is determined. The presence of additional resistance at the outlet from well changes its characteristic. It is shown that the effect of the additional resistance may contribute to a coordination point at stability area, while the condition of the flow stability in well trunk is not executed. Such a flow, which is essentially unstable, where development of instability is constrained by the influence resistance downstream, is proposed as pseudo stable. Inversion of graphics performance of steam-water geothermal wells is explained via pseudo stability. Importance of taking into account the specific pseudo stable flow at formulating technical solutions to improve efficiency in the use of wells at exploitation of geothermal power plants is noted.The study was performed with financial support by the Russian Foundation for Basic Research, research project No. 16-05-00398 а.
: 622.32: 532.529Authors
: Shulyupin A. N.
Shulyupin A.N., Doctor of Technical Sciences, Science and Innovative Deputy Director, Institute of Mining of Far Eastern Branch of Russian Academy of Sciences,
680000, Khabarovsk, Russia, e-mail: firstname.lastname@example.org.Key words
Steam-water flow, stability, indicator characteristic, geothermal well, aquifer, graph of productivity, bottomhole pressure, flow-rate.References
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