Shevelova H.M., Tynyna S.V. Ways of a two-phase flow control in the jet mill ejector channels

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Parent Category: Geo-Technical Mechanics, 2019

Category: Geo-Technical Mechanics, 2019, Issue 144

Geoteh. meh. 2019, 144, 190-198

https://doi.org/10.15407/geotm2019.144.190

Ways of a two-phase flow control in the jet mill ejector channels

¹Shevelova H.M., ²Tynyna S.V.

¹Institute of Technical Mechanics under the NAS of Ukraine and State Space Agency of Ukraine, ²Institute of Geotechnical Mechanics named by N. Poljakov NAS of Ukraine

UDC 662.210.587.621.572

Language: Russian

Abstract.

The efficiency of gas-dispersed flow controlling in the jet mill channels affects the quality of the grinding process.

In the article the methods of the two-phase dispersed flows controlling in the mill ejector channels have been analyzed. The examples of control schemes have been considered due to the gas supply at the exit from the ejector accelerating tube and due to the geometrical influence by means of several annular slots and the angle of their inclination. The advantages and disadvantages of each of the designs have been showed. Have been revealed that the most effective control method is the combined one, in which gas-dynamic and geometric effects on the main flow are carried out together.

Geometric effects include the angle of the additional flow of gas; the ratio of the areas of the output section of the ejecting gas nozzle and the holes through which additional flow enters, and the shape, number and location of the holes. Gas-dynamic effects include the pressure ratio of the main and additional energy flow.

The characteristics of the ejector with an additional gas supply have been investigated. They include the ratio of the critical sections areas of the blowing nozzle and the main nozzle, the reduced flow rate of the blown gas, and the degree of compression of the ejector.

A comparative analysis of the characteristics of a single-stage ejector and an ejector with injection into the mixing chamber with the same geometrical parameter f^* = 0.09, where f^* is the ratio of the area of the ejector gas nozzle output section to the area of the inlet tube have been carried out.

The calculations showed that the compression ratio of the ejector with an additional gas supply is 3.2 times more than the compression ratio of a single-stage ejector. The advantage of the blower ejector is revealed in the range of values of the ejection coefficient n from 0 to 0.1. In addition, in this range, the blower ejector operates at lower pressure ratios.

A schematic diagram of two-phase flow control has been presented, which is carried out due to the axial supply of additional energy carrier to the accelerating tube of the ejector. The most effective control will be if the distance between the annular leads is from two to eight diameters of the acceleration tube, and the number of slit holes along the tube length is two or more.

Keywords:

two-phase flow control, wear, jet mill ejector, additional supply of energy carrier, gas-dynamic and geometric effects

References:

1. Uvarov, V., Bogdanov, B., Bulgakov, S., Karpachev, D., Belgorodskij gosudarstvennyj tehnologicheskij universitet im. V. G. Shuhova (2002), Protivotochnaja strujnaja melnica [Counter Flow Jet Mill], Federal Service for Intellectual Property (Rospatent), Moscow, RU, Pat. 2188077.

 2. Tretjakov, A., Belov, A., Zavadskij, G., Gumarov, R., Razumov, S., Belonogov, L., Barkovec, A. Gosudarstvennyj vsesojuznyj nauchno-issledovatel'skij institut cementnoj promyshlennosti (1990), Jezhektor strujnoj melnicy [Jet Mill Ejector], USSR State Committee on Inventions and Discoveries, SU, A.s. 1607949.

 3. Grabovskyj, G., Grygoru, V., Kyrpach, M., Nedbayev, M. Kyyivskyj nacionalnyj universytet im. T. Shevchenka (2013), Ezhektor strumenevogo mlina [Jet Mill Ejector], State Register of Patents of Ukraine, Kyiv, UA, Pat. 100638.

 4. Shushin, N.A. (2010), "Gas ejector with tangential injection into the mixing chamber", Uchenye zapiski CAGI, no. 3, pp. 69-81.

https://doi.org/10.1615/TsAGISciJ.v41.i3.60

 5. Shevelova, H.M. (2018), "Methods of improving of the finished product quality at the jet milling", Zbagachennja korysnyh kopalyn, no. 69 (110), pp. 86-94.

 6. Sheveleva, A.M. (2018), "Improvement of an experimental model of a jet mill ejector unit", Molodye uchenye 2018 - ot teorii k praktike: Materialy IX-oj mezhdunarodnoj konferencii [Young scientists 2018 - from theory to practice: Proceedings of the IXth International Conference], Dnipro, UA, February, pp. 89-90.

 7. Shevelova, H.M. and Tynyna, S.V. (2016), "Linear regression model of the additional gas supply effect in the chamber of the jet mill ejector", Zbagachennja korysnyh kopalyn, no. 64 (105), pp. 78-86.

 

About the authors:

Shevelova Hanna Myhajlivna, Master of Science, Junior Researcher in the Institute of Technical Mechanics under the National Academy of Sciences of Ukraine and State Space Agency of Ukraine (ITM, NASU & SSAU), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .

Tynyna Sergii Volodymyrovych,Candidate of Technical Sciences (Ph.D.), Senior Researcher in Department of Elastomeric Component Mechanics in Mining Machines, Institute of Geotechnical Mechanics named by N. Polyakov of National Academy of Science of Ukraine (IGTM NASU), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .

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