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Research Papers

Film Cooling Extraction Effects on the Aero-Thermal Characteristics of Rib Roughened Cooling Channel Flow

[+] Author and Article Information
Beni Cukurel

e-mail: cukurel@vki.ac.be

Claudio Selcan

e-mail: selcan@vki.ac.be

Tony Arts

e-mail: arts@vki.ac.be
von Karman Institute for Fluid Dynamics,
Chaussée de Waterloo, 72, B-1640,
Rhode-St-Genèse, Belgium

Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the Journal of Turbomachinery. Manuscript received June 28, 2012; final manuscript received August 5, 2012; published online November 2, 2012. Editor: David Wisler.

J. Turbomach 135(2), 021016 (Nov 02, 2012) (12 pages) Paper No: TURBO-12-1084; doi: 10.1115/1.4007501 History: Received June 28, 2012; Revised August 05, 2012

The present study is geared towards quantifying the effects of film cooling holes on turbine internal cooling passages. In this regard, tests are conducted in a generic stationary model, with evenly distributed rib-type perturbators at 90 deg, constituting a passage blockage ratio of H/Dh = 0.3 and pitch-to-height ratio of P/H = 10. The 1/3H diameter surface-perpendicular film cooling holes are employed at a distance of 5/3H downstream of the preceding rib. Through liquid crystal thermometry measurements, the aero-thermal effects of a change in suction ratio are contrasted for various configurations (Re = 40,000 SR = 0–6), and compared with the analogous aerodynamic literature, enabling heat transfer distributions to be associated with distinct flow structures. At increased suction ratio, the size of the separation bubble downstream of the rib is observed to diminish, triggering globally an earlier reattachment; in addition to low-momentum hot fluid extraction via film cooling suction. Hence, in the presence of active flow extraction, higher overall heat transfer characteristics are observed throughout the channel. Moreover, the findings are generalized via friction factor and Nusselt number correlations, along with an analytical 20-pitch passage model. SR ∼ 3.5 is observed to provide favorable characteristics of pitch-to-pitch uniform suction ratio, lack of hot fluid ingestion and to sustain the highest passage averaged heat transfer.

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References

Bunker, R. S., and Bailey, J. C., 2001, “Film Cooling Discharge Coefficient Measurements in a Turbulated Passage With Internal Crossflow,” ASME J. Turbomach., 123(4), pp. 774–780. [CrossRef]
Chanteloup, D., and Bölcs, A., 2002, “Flow Characteristics in Two-Leg Internal Coolant Passages of Gas Turbine Airfoils With Film-Cooling Hole Ejection,” ASME J. Turbomach., 124(3), pp. 499–507. [CrossRef]
Sheepers, G., and Morris, R. M., 2009, “Experimental Study of Heat Transfer Augmentation Near the Entrance to a Film Cooling Hole in a Turbine Blade Cooling Passage,” ASME J. Turbomach., 131, p. 4. [CrossRef]
Thurman, D., and Poinsatte, P., 2001, “Experimental Heat Transfer and Bulk Air Temperature Measurements for a Multipass Internal Cooling Model With Ribs and Bleed,” ASME J. Turbomach., 123(1), pp. 90–96. [CrossRef]
Shen, J. R., Wang, Z., Ireland, P. T., Jones, T. V., and Byerley, A. R., 1996, “Heat Transfer Enhancement Within a Turbine Blade Cooling Passage Using Ribs and Combinations of Ribs With Film Cooling Holes,” ASME J. Turbomach., 118, pp. 428–434. [CrossRef]
Taslim, M. E., Li, T., and Spring, S. D., 1995, “Experimental Study of the Effects of Bleed Holes on Heat Transfer and Pressure Drop in Trapezoidal Passages With Tapered Turbulators,” ASME J. Turbomach., 117, pp. 281–289. [CrossRef]
Han, J. C., 1984, “Heat Transfer and Friction in Channels With Two Opposite Rib-Roughened Walls,” ASME J. Heat Transfer, 106, pp. 774–781. [CrossRef]
Han, J. C., 1988, “Heat Transfer and Friction Characteristics in Rectangular Channels With Rib Turbulators,” ASME J. Heat Transfer, 110, pp. 321–328. [CrossRef]
Kim, K. M., Park, S. H., Jeon, Y. H., Lee, D. H., and Cho, H. H., 2008, “Heat/Mass Transfer Characteristics in Angled Ribbed Channels With Various Bleed Ratios and Rotation Numbers,” ASME J. Turbomach., 130(3), p. 031021. [CrossRef]
Casarsa, L., Cakan, M., and Arts, T., 2002, “Characterization of the Velocity and Heat Transfer Fields in an Internal Cooling Channel With High Blockage Ratio,” ASME Paper No. GT-2002-30207.
Casarsa, L., and Arts, T., 2005, “Experimental Investigation of the Aerothermal Performance of a High Blockage Rib-Roughened Cooling Channel,” ASME J. Turbomach., 127(3), pp. 580–588. [CrossRef]
Lohász, M. M., Rambaud, P., and Benocci, C., 2006, “Flow Features in a Fully Developed Ribbed Duct Flow as a Result of MILES,” Flow Turbulence Combust., 77(1–4), pp. 59–76. [CrossRef]
Soto, F. J. G., 2011, “Investigation of Interaction of Coherent Structures on Heat Transfer in Ribbed Duct,” von Karman Institute for Fluid Dynamics, Diploma Course Report.
Cukurel, B., Selcan, C., and Arts, T., 2012, “Color Theory Perception of Steady Wide Band Liquid Crystal Thermometry,” Exp. Therm. Fluid Sci. 2012, Vol. 39, pp. 112–122.
Kline, S. J., and McClintock, F. A., 1953, “Describing Uncertainties in Single-Sample Experiments,” Mech. Eng., 75, pp. 3–8.
Zukauskas, V. A., and Pedisius, K. A., 1987, “Heat Transfer to Reattached Fluid Flow Downstream of a Fence,” Wärme- und Stoffübertragung, 21, pp. 125–131. [CrossRef]
Eaton, J. K., and Johnston, J. P., 1981, “A Review on Subsonic Turbulent Flow Reattachment,” AIAA J., 19(9), pp. 1093–1100. [CrossRef]
Eaton, J. K., and Vogel, J. C., 1985, “Combined Heat Transfer and Fluid Dynamic Measurements Downstream of a Backward-Facing Step,” ASME J. Heat Transfer, 107, p. 922. [CrossRef]
Sparrow, E. M., Kang, S. S., and Chuck, W., 1987, “Relation Between the Points of Flow Reattachment and Maximum Heat Transfer for Regions of Flow Separation,” Int. J. Heat Mass Transfer, 30(7), pp. 1237–1246. [CrossRef]
Metzger, D. E., Chyu, M. K., and Bunker, R. S., 1988, “The Contribution of On-Rib Heat Transfer Coefficients to Total Heat Transfer From Rib-Roughened Surfaces,” Transport Phenomena in Rotating Machinery, J. H.Kim, ed., Hemisphere, Washington, D.C.

Figures

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Fig. 1

Schematic of the experimental setup

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Fig. 2

Typical hue temperature calibration curve

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Fig. 3

Convective ribbed wall perspective mapping

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Fig. 4

Normalized heat flux distribution around a hole

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Fig. 5

Normalized heat flux distribution around a rib

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Fig. 6

Visualization of the ribbed channel flow field [11]

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Fig. 7

Rib downstream flow (a) without film cooling hole (b) with film cooling hole [13]

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Fig. 8

Effects of suction ratio on EF distributions

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Fig. 9

Laterally averaged EF at various suction ratios

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Fig. 10

Generalized cooling hole setup—control volumes

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Fig. 11

Wall friction factor at various suction ratios

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Fig. 12

20 Blade model—local SR at each pitch

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Fig. 13

Blade model—Nusselt number average up until each pitch

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