CONTROL OF FLOW STRUCTURE INSIDE SEMI-CYLINDRICAL TRENCH
DOI:
https://doi.org/10.20535/2305-9001.2016.78.85329Keywords:
coherent vortical structures, semi-cylindrical trench, boundary layer, thermoanemometer, powder-like visualization, current structure controlAbstract
The purpose of research is search and testing of new means of coherent vortical structures control in boundary layers, what can be used for control of heat and mass transfer processes. Experimental study of current inside semi-cylindrical trench on flat surface was carried out in the wind-channel of the opened type using thermoanemometer and powder-like method of visualization. Investigation was realized in semi-cylindrical cavity which was disposed across to undisturbed stream for the flow Reynolds number according to length of plate (from its beginning to the trench midpoint) 1.23×105. Ratio of cavity diameter to its length was 0.23. The coherent vortical structures inside of trench were discovered and investigated for cases of absence and existence of control actions by means of setting along the trench length of various screens on leading edge of cavity regarding to the incident flow and also on back edge of cavity. It is shown that depending from different location of screens it is possible to influence substantially on a vortex motion in cavity, and choice of certain configuration of controlling screens gives the possibility to obtain or the complete preservation of monodispersible powder in cavity, either, if is necessary, complete breaking out of powder from cavity. Thus applied control means allow to comprehend and to employ the mechanism of current structure control and accordingly heat and mass transfer processes on exposed surfaces of aircraft, cosmic, marine, power technique.
References
Yermishin, A.V. and Isayev, S.A. (ed.) (2001), Upravlyenije obtyekanijem tel s vikhryevymi yacheiykami v prilozhenii k lyetatyelnym apparatam integralnoiy komponovki [Flow control of bodies with vortex cells in application to aircrafts of integral assembly], Moscow–St. Petersburg, Russia.
Gortyshov, Yu.F., Popov, I.A., Olimpijev, V.V. and dr. (2009), Teplogidravlichyeskaja effektivnost pyerspyektivnych sposobov intensifikatsii teplootdachi v kanalakh teploobmyennogo oborudovanija [Thermohydraulic efficiency of perspective methods of heat transfer intensification in heat exchangers channels], Tsentr innovatsionnych technology, Kazan, Russia.
Khalatov, A.A. (2005), Heat transfer and fluid mechanics over surface indentations (dimples), National Academy of Sciences of Ukraine, Institute of Engineering Thermophysics, Kiev, Ukraine.
Ashcroft, G. and Zhang, X. (2005), “Vortical structures over rectangular cavities at low speed”, Phys. Fluids., vol. 17, no 1, pp. 5104-1–5104-8.
Isayev, S.A., Leont’jev, A.I. and Kornev, N.V. (2008), “Chislennoje modelirovanije smyerchyevogo teploobmyena pri obyekanii povyerkhnosteiy s lunkami”, VI Minskiiy Mezhd. Forum po Teploobmenu [VI Minsk International Forum on Heat Tranfer], MMF 2008, Minsk, Byelorussia, 2008, pp. 1–9.
Kiknadze, G.I, Gachyechiladze, I.A. and Alyeksyeyev V.A. (2005), Samoorganizatsija smyerchyeobraznykh struiy v potokakh vyazkikh sploshnykh sryed I intensifikatsija tyeploobmyena, soprovozhdayushchaya eto yavlyeniye [Self-organization of tornado-imaginable jets in viscous continuous media and intensification of heat and mass exchange escorting this phenomenon], Moscow, Russia.
Leont’jev, A.I., Olimpiyev, V.V., Dilyevskaja, Ye.V. and Isayev, S.A. (2002), “Sushchyestvo mekhanizma intensifikatsii teploobmena na poverkhnosti so sfyerichyeskimi lunkami”, Izv. RAN. Energyetika [Proceedings of Russian Academy of Science. Power Engineering], no 2, pp. 117–135.
Jacquin, L., Forestier, N. and Geffroy, P. (2001), “Small scale production in the coherent structures of a shear flow over an open cavity” Turbulence and Shear Flow Phenomena, in E. Lindborg, A. Johansson and dr. (ed.), vol. 1., Stockholm, Sweden, pp. 413–418.
Lin, J.C. and Rockwell, D. (2001), “Organized oscillations of initially turbulent flow past a cavity”, AIAA J., vol. 39, no 6, pp. 1139–1151.
Ligrani, P.M., Burgess, N.K. and Won, S.Y. (2004), “Nusselt numbers and flow structure on and above a shallow dimpled surface within a channel including effects of inlet turbulence intensity level”, ASME Paper GT2004-54231, no 5423, pp. 1–23.
Voskobijnik, V.A. (2013), “Spatially-frequency characteristics of coherent structures, velocity and pressure fields in dimple generators of vortices”, Synopsis of thesis of technical science doctor on mechanics of fluid, gas and plasma, National Academy of Sciences of Ukraine, Institute of hydromechanics, Kyiv, Ukraine.
Ahuja, K.K. and Mendoza, J. (1995), “Effects of cavity dimensions, boundary layer and temperature on cavity noise with emphasis on benchmark data to validate computational aeroacoustic codes”, NASA Contractor Report, no 4653, pp. 1–284.
Bres, G.A. and Colonius, T. (2008), “Three-dimensional instabilities in compressible flow over open cavities”, J. Fluid Mech., vol. 599, pp. 309–339.
Faure, T.M., Adrianos, P., Lusseyran, F. and Pastur, L. (2007), “Visualizations of the flow inside an open cavity at medium range Reynolds numbers”, Exp. Fluids, vol. 42, pp.169–184.
Bres, G.A. and Colonius, T. (2007), “Direct numerical simulations of three-dimensional cavity flows”, AIAA Pap., № 3405, pp. 1–16.
de Vicente, J., Basley, J., Meseguer-Garrido, F., Soria, J. and Theofilis, V. (2014), “Three-dimensional instabilities over a rectangular open cavity: from linear stability analysis to experimentation”, J. Fluid Mech., vol. 748, pp. 189–220.
Larcheveque, L., Sagaut, P. and Labbe, O. (2007), “Large-eddy simulation of a subsonic cavity flow including asymmetric three-dimensional effects”, J. Fluid Mech., vol. 577, pp. 105–126.
Rockwell, D. and Knisely, C. (1979), “The organized nature of flow impingement upon a corner”, J. Fluid Mech., vol. 93, pp. 413–434.
Isayev, S.A., Kudinov, P.I., Kudryavtsev, N.A. and Pyshnyij, I.A. (2003), “Chislyennyi analiz strujino-vikhrevoyi kartiny tyechyenija v pryamougolnoyi transheye”, IFZh [Engineering Physical Journal], vol. 76, no 2, pp. 24–30.
Isayev, S.A., Leont’jev, A.I., Kiknadze, G.I and dr. (2005), “Sravnityel’nyi analiz vikhryevogo tyeploobmyena pri turbulyentnom obtyekanii sfyerichyeskoyi lunki I dvumyernoyi transheji na ploskoyi stenkye”, IFZh [Engineering Physical Journal], vol. 78, no 4, pp. 117–128.
Isayev, S.A., Leont’jev, A.I., Baranov, P.A. and dr. (2001), “Chislyennyi analiz vlyijaniya vyazkosti na vikhryevuyu dinamiku pri laminarnom otryvnom obtyekanii lunki na ploskosti s uchetom yeje asimmetrii”, IFZh [Engineering Physical Journal], vol. 74, no 2, pp. 62–678.
Turick, V.N., Babenko, V.V., Voskobojinick, V.A. and Voskobojinick, A.V. (2011), “Vikhryevoye dvizheniye v polutsilindricheskoyi kanavkye na plastinye”, Promyslova gidravlika i pnevmatika [Industrial Hydraulics and Pneumatics], vol. 33, no 3, pp. 23–27.
Voskobojinick, A.V. (2005), “Coherent structures forming in swirling flows and indentations”, Synopsis of thesis of technical science PhD on mechanics of fluid, gas and plasma, National Academy of Sciences of Ukraine, Institute of hydromechanics, Kyiv, Ukraine.
Turick, V.N., Voskobijinick, V.A. and Voskobijinick, A.V. (2012), “Vplyv napivtsilindrychnoji kanavky na integral’ni kharakteristiki prymezhovogo sharu nad plastynoyu”, Bulletin of NTUU “KPI”, Journal of Mechanical Engineering, no 64, pp. 47–55.
Voskobijinick, A.V. and Voskobijinick, V.A. (2007), “Kinematyka vykhrovogo rukhu na obtichniyi poverkhni z napivtsilindrychnoju kanavkoju”, Acoustic Bulletin, vol. 10, no 3, pp. 30–41. 26. Voskobojinick, A.V. and Voskobojinick, V.A. (2007), “Polye skorostyei v pogranichnom sloye nad plastinoyi s polutsilindricheskoyi kanavkoyi”, Bulletin of Donetsk University, Ser. A: Natural Sciences, no 1, pp. 127–135.
