Effect of Geometric Parameters of Working Channel of Hydrodynamic Filter with Protective Baffle on Medium Flow Structure

The purification of fluids from solid mechanical impurities remains one of the most important technical tasks from the viewpoint of ecological safety and reliability improvement of technical system operation. One of the most promising devices for cleaning fluids is the hydrodynamic filter, in which tangential filtration is combined with centrifugal separation during rotation of the filtering and protective cylindrical baffles. It is essential to study the effect of geometric parameters of the working channel of the hydrodynamic filter with a protective baffle on the medium flow structure. This allows us to determine the relationship between the regime and geometric dimensions of the filter, which ensures the maximum efficiency of centrifugal separation and the filter life at minimum costs. The study was carried out by mathematical modeling of the flow in the hydrodynamic filter with rotating protective and filtering baffles. The system of equations was constructed on the basis of Navier --- Stokes equations using the turbulence model k--ε. This paper studied the effect of geometrical design parameters of the filter on the vortex formation, the taper angle of the hydrodynamic filter housing and the width of the annular gap between the stationary housing and the rotating protective baffle. The results suggest that an increase in the width of the annular channel and the taper angle of the filter housing lead to the intensification of the circulation flow with the formation of secondary vortex structures. The velocity distribution in the hydrodynamic filter working channel is obtained for various geometric and regime parameters. Findings of the research show that in the considered range of regime and design parameters the rotation of the fluid between two baffles of the hydrodynamic filter is not analogous to the rotation of an absolutely rigid body. It is necessary to carry out similar studies for a two-phase disperse system to evaluate the use of the protective baffle for the separation efficiency. These analytical and experimental studies are the subject of the next stage of work on this issue

References

[1] Devisilov V.A., Sharay E.Yu. Hydrodynamic Filtration. Bezopasnost v tekhnosfere [Safety in Technosphere], 2015, vol. 4, no. 3, pp. 68–80 (in Russ.).

[2] Devisilov V.A., Myagkov I.A., Lvov V.A., Sharay E.Yu. Analytical model of suspensions separation in hydrodynamic filter with pivoting perforated partition. Bezopasnost v tekhnosfere [Safety in Technosphere], 2014, vol. 3, no. 5, pp. 32–41 (in Russ.).

[3] Devisilov V.A., Myagkov I.A., Lvov V.A., Sharay E.Yu. Regeneriruemyy filtr [Regenerative filter]. Patent 149136 RF. Appl. 04.08.2014, publ. 20.12.2014 (in Russ.).

[4] Devisilov V.A., Sharai E.Yu. Numerical study of the flow structure in a hydrodynamic filter. Theoretical Foundations of Chemical Engineering, 2016, vol. 50, iss. 2, pp. 209–216. DOI: 10.1134/S0040579516020044

[5] Devisilov V.A., Sharai E.Yu. Hydrodynamics of a rheologically complicated liquid in a self-cleaning filter. Theoretical Foundations of Chemical Engineering, 2012, vol. 46, iss. 6, pp. 594–600. DOI: 10.1134/S004057951

[6] Devisilov V.A., Sharay E.Yu., Agalakova N.A. Investigation of the hydraulic characteristics of fluid flow in hydrodynamic filter with tangential flow swirling. Vektor nauki TGU, 2013, no. 2 (24), pp. 32–37 (in Russ.).

[7] Aleksandrov A.A., Devisilov V.A., Sharay E. Hydrodynamic non-Newtonian liquid-solid flow in compound Taylor — Couette flow. Proc. 9th Int. Conf. on Multiphase Flow (ICMF 2016). Firenze, Italy. 2016. P. 105–108.

[8] Aleksandrov A., Devisilov V., Sharai E. Hydrodynamic vibratory filtration as a method removing of mechanical impurities in regeneration systems of highly viscous working fluids. Proc. 10th Int. Conf. on Sustainable Energy and Environmental Protection. Mechanical Engineering (SEEP 2017), 2017. P. 77–86.

[9] Mochalin E.V. Hydrodynamic resistance of rotary filter with improved structure. Vostochno-Evropeyskiy zhurnal peredovykh tekhnologiy. Ser. Prikladnaya mekhanika [Eastern-European Journal of Enterprise Technologies. Ser. Applied Mechanics], 2001, no. 2/7 (50), pp. 31–34 (in Russ.).

[10] Mochalin E.V., Petrenko O.V., Kriavosheya P.M., Ivanova O.O. Filtr dlya ochishchennya ridin [Filter for liquid depuration]. Patent 64474 A Ukraine. Appl. 09.06.2003, publ. 16.02.2004.

[11] Gortler H., Angew Z. Dreidimensionales zur stabilitatstheorie laminarer grenzschichten. Math. Mech., 1955, vol. 35, no. 9-10, pp. 362–363.

[12] Wimmer M. Tailor vortices at different geometries. In: Physics of Rotating Fluids. Springer, 2000. P. 194−212.

[13] Noui-Mehidi M.N. Design optimization of a conical annular centrifugal contractor. Fluid Dynamics & Materials Processing, 2011, vol. 7, no. 2, pp. 141–152. DOI: 10.3970/fdmp.2011.007.141

[14] Zhang Y., Xu L., Li D. Numerical computation of end plate effect on Taylor vortices between rotating conical cylinder. Communications in Nonlinear Science and Numerical Simulation, 2012, vol. 17, iss. 1, pp. 235–241. DOI: 10.1016/j.cnsns.2011.05.021

[15] Lalaoua A., Chaieb Z. Flow patterns in a combined Taylor — Couette geometry. Topical Problems of Fluid Mechanics, 2016, pp. 109–118. DOI: 10.14311/TPFM.2016.016 Available at: http://www.it.cas.cz/fm/im/im/proceeding/2016/16

[16] Xu X., Wen P., Xu L., Cao D. Occurrence of Taylor vortices in the flow between two rotating conical cylinders. Communications in Nonlinear Science and Numerical Simulation, 2010, vol. 15, iss. 5, pp. 1228–1239. DOI: 10.1016/j.cnsns.2009.05.061

[17] Dou H.-S., Khoo B.C., Yeo K.S. Instability of Taylor — Couette flow between concentric rotating cylinders. Inter. J. of  Thermal Science, 2008, vol. 47, no. 11, pp. 1422–1435. DOI: 10.1016/j.ijthermalsci.2007.12.012

[18] Li Q.S., Wen P., Xu L.X. Transition to Taylor vortex flow between rotating conical cylinders. Journal of Hydrodynamics, 2010, vol. 22, iss. 2, pp. 241–245. DOI: 10.1016/S1001-6058(09)60050-0

[19] Taylor G.I. Stability of a viscous liquid contained between two rotating cylinders. Phil. Trans. Roy. Soc. London. Ser. A, 1923, vol. 223, pp. 289–293.

[20] Finkelshteyn Z.L. Primenenie i ochistka rabochikh zhidkostey dlya gornykh mashin [Application and depuration of process fluids for mining machines]. Moscow, Nedra Publ., 1986. 232 p.

[21] Shevchuk I.V. Convective heat and mass transfer in rotating disk systems. Springer, 2009. 236 p.

[22] Volkov K.N., Emelyanov V.N. Modelirovanie krupnykh vikhrey v raschetakh turbulentnykh techeniy [Large vortex simulation in calculation of turbulent flows]. Moscow, Fizmatlit Publ., 2008. 368 p.

[23] Devisilov V.A., Sharay E.Yu. Current stability limits in hydrodynamic filter safety in technosphere. Bezopasnost v tekhnosfere [Safety in Technosphere], 2013, vol. 2, no. 4, pp. 23–29 (in Russ.).

[24] Mochalin E.V. Fluid flow stability outside the rotating mesh filter element. Vestnik SumDU, 2006, no. 12 (96), pp. 23–32 (in Russ.).

[25] Greenspan Harvey P. The theory of rotating fluids. Cambridge University Press, 1968. 340 p.