Augmentation Factors of the Film Cooling Configuration Using Two Rows of Inclined Cylindrical Holes Placed Inside Hemispherical Dimples
The modern high-performance gas turbine engines operate at the temperatures exceeding the melting temperature of construction materials, which require the blade cooling. Usually the gas turbine blades apply high-developed cooling system including the external film cooling promoting the higher operational durability and longer blade service life. Then film cooling efficiency depends strongly from the method of coolant supply onto the blade surface. Currently the published results contain some data, regarding the type of coolant supply. Analysis of this data has shown that coolant supply into hemispherical dimple is one of the perspective schemes, providing the high rate of film cooling efficiency. The interesting scientific task is investigation of physical structure near the cooled surface and identification of reasons influencing greater film cooling efficiency compared with traditional cooling technique. For this reason using the ink spot technique the surface streamline visualization was performed for the traditional cooling scheme, as well as the coolant supply into hemispherical dimples. The numerical simulation was made using ANSYS CFX 14 code along with k-eturbulence model, the blowing factor was varied from 0.5 to 2.0. The analysis of results obtained has shown that scheme with a coolant supply into hemispherical dimples reduces the flow separation length and the intensity of pair ("kidney") vortex.
Davidson, F. D., Kistenmacher, D. and Bogard, D. (2012), "Film cooling with a thermal barriercoating:roundholes,cratersandtrenches", Journal of Turbomachinery, Vol. 136 No. 4, pp. 1757–1768,doi:10.1115/GT2012-70029.
Lu, Y., Dhungel, A., Ekkad, V. and Bunker, R. S. (2009), "Effect of trench width and depth on film cooling from cylindricalholesembedded in trenches", Journal of Turbomachinery, Vol. 131 No. 1, pp. 011003–011013, doi:10.1115/1.2950057.
Colban, W. F., Thole, K. A. and Bogard, D. (2010), "A film-cooling correlation for shaped holes on a flat-platesurface",Journal of Turbomachinery. Vol. 133, pp. 011002-1–11002-11, doi:10.1115/1.4002064.
Khalatov, A. A., Borisov, I. I., Panchenko, N. A., Dashevskyy, Yu. J. and Kovalenko, A. S. (2014), "Flat plate film coolingfroma double jet holes: influence of free-stream turbulence and flow acceleration", ThermophysicsandAeromechanics,Vol.21No.5, pp. 545–552, ISSN 0869-8643, doi: 10.1134/S0869864314050023.
Petelchyts, V. Yu., Pysmennyi, D. N. and Dashevskyy, Yu. Ya. (2015), "Vliyanie orientatsii ryadov otverstiy natsilindricheskomuchastke vhodnoy kromki na effektivnost plenochnogo ohlazhdeniya [Influence ProducedbytheOrientationofSlotRows in the Cylindrical Section of the Entrance Edge on the Film Deposition Efficiency]²,BulletinofNTU"KhPI". Series: Powerandheat engineering processes and equipment, no. 15(1124), pp. 69–75.ISSN2078-774Х.
Khalatov, A. A., Varhanov, I. V. and Kovalenko, H. V., "Institute of engineering thermophysics (2004) "Sposibplivkovogooholodzhennya ta pristriy dlya yogo zdiysnennya [Method of film cooling and appliance foritsimplementation]",StateRegisterofPatents of Ukraine, Kiev, UA, Pat. No. 47749.
Khalatov, A. A., Borisov, I. I., Panchenko, N. A., Bezliudna, M. V. and Dashevskyy, Yu. J. (2014),²Eksperimentalnoeissledovanie dvuhryadnyih shem plenochnogo ohlazhdeniya [The experimental study of doublerowfilmcoolingschemes]²,Reportsof VI Russian National Conference on Heat Transfer, 27-31 Oct. [Electronic],MEIPublishingHouse,Moscow, Russian.
Khalatov А. А., Borisov I. I., Bezludna M. V., Panchenko N. A. and Dashevskyy Yu. J. (2015), ²Perspektivnyiesposobyiplenochnogo ohlazhdeniya: vliyanie uskoreniya osnovnogo potoka [Advanced Methods of theFilmDeposition:InfluenceoftheAcceleration of the Main Flow], Bulletin of NTU "KhPI". Series: Power andheatengineeringprocessesand equipment,No.15(1124), pp. 56–62. ISSN 2078-774Х.
Khalatov, A. A., Bezliudna, M. V., Dashevskyy, Yu. J., Severin, S. D. and Borisov, I. I. (2013), ²Plenochnoeohlazhdenieploskoy plastinyi pri vyiduve ohladitelya cherez kruglyie otverstiya v dvuhryadnoy sistemesfericheskihuglubleniy[Tapecoolingofthe flat plate of the cooler blow throught round opening in two-row systemofsphericaldeepenings]²,Pumps.Turbines.Systems, No. 4(9), pp. 47–55, ISSN 2226-177X.
Kovalenko, H. V. and Khalatov, A. A. (2008), ²Granitsyi rezhimov techeniya v uglubleniyah na ploskoypoverhnosti,imeyuschih formu sfericheskih segmentov [The boundaries of flow regimes in the pits on a flat surfaceintheshapeofsphericalsegments]², Applied Hydromechanics, Vol. 10(82) No 1, pp. 23–32, ISSN 1561-9087.