Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30184
Design and Characteristics of New Test Facility for Flat Plate Boundary Layer Research

Authors: N. Patten, T. M. Young, P. Griffin

Abstract:

Preliminary results for a new flat plate test facility are presented here in the form of Computational Fluid Dynamics (CFD), flow visualisation, pressure measurements and thermal anemometry. The results from the CFD and flow visualisation show the effectiveness of the plate design, with the trailing edge flap anchoring the stagnation point on the working surface and reducing the extent of the leading edge separation. The flow visualization technique demonstrates the two-dimensionality of the flow in the location where the thermal anemometry measurements are obtained. Measurements of the boundary layer mean velocity profiles compare favourably with the Blasius solution, thereby allowing for comparison of future measurements with the wealth of data available on zero pressure gradient Blasius flows. Results for the skin friction, boundary layer thickness, frictional velocity and wall shear stress are shown to agree well with the Blasius theory, with a maximum experimental deviation from theory of 5%. Two turbulence generating grids have been designed and characterized and it is shown that the turbulence decay downstream of both grids agrees with established correlations. It is also demonstrated that there is little dependence of turbulence on the freestream velocity.

Keywords: CFD, Flow Visualisation, Thermal Anemometry, Turbulence Grids.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1072453

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1469

References:


[1] M. F. Blair, "Boundary Layer Transition in Accelerating Flows with Intense Freestream Turbulence: Part 1 - Disturbances Upstream of Transition Onset", J. Turbomachinary, Vol. 114, 1992, pp. 313 - 321.
[2] J. Fransson, M. Matsubara, and P. Alfredsson, "Transition Induced by Freestream Turbulence", J. Fluid Mechanics, Vol. 527, 2005, pp. 1-25.
[3] P. E. Roach, and D. H. Brierley, "The Influence of a Turbulent Free- Stream on Zero Pressure Gradient Transitional Boundary Layer Development", Part 1 test cases t3a and t3b: ERCOFTAC Workshop, Lausanne, France, 1990.
[4] M. Matsubara, and P. Alfredsson, "Disturbance Growth in Boundary Layers Subjected to Freestream Turbulence", J. Fluid Mechanics, Vol. 430, 2001, pp. 149-168.
[5] J. Wesin, "Laminar - Turbulent Boundary Layer Transition Influenced by Freestream Turbulence". PhD dissertation, Dept. Mechanics, KTH, Stockholm, Sweden, 1997.
[6] K. J. Westin, A. V. Boiko, B. G. Klingmann, V. V. Kozlov, and P. H. Alfredsson, "Experiments in a Boundary Layer Subjected to Free Stream Turbulence. Part 1. Boundary Layer Structure and Receptivity", J. Fluid Mechanics, Vol. 281, 1994, pp. 193-218.
[7] M. V. Morkovin, "Bypass Transition to Turbulence and Research Desiderata", Transition in Turbines, NASA-CP-2386, 1984, pp.161-294.
[8] W. Saric, H. Reed, and E. Kerschen, "Boundary-Layer Receptivity to Freestream Disturbances", Annual Rev. Fluid Mechanics, Vol. 34, 2002, pp. 291-319.
[9] T. Herbert, "Boundary Layer Transition - Analysis and Prediction Revisited", AIAA-91-0737, 29th Aerospace Sciences Meeting. Jan 7-10, Reno, Nevada, 1991.
[10] V. M. Filippov, "Influence of Plate Nose Heating on Boundary Layer Development", J. Fluid Dynamics , Vol. 37, No. 1, 2002, pp. 27-36.
[11] B. Abu-Ghannam, and R. Shaw, "Natural Transition of Boundary Layers - The Effects of Turbulence, Pressure Gradient, and Flow History", IMechE 22, 1980, pp 213-228.
[12] K. H. Sohn, J. E. O-Brien, and E. Reshotko, "Some Characteristics of Bypass Transition in a Heated Boundary Layer", NASA TM 102126,1989.
[13] J. P. Holman, Heat Transfer, 8th Edition, New-York; London: McGraw- Hill, USA, 1997.
[14] J. Cousteix, "Basic Concept on Boundary Layers", AGARD Report No. 786, Special Course on Skin Friction Drag Reduction, 1992.
[15] D. Zhou, and T. Wang, "Effects of Elevated Freestream Turbulence on Flow and Thermal Structures in Transitional Boundary Layers", J. Turbomach, Vol. 117, 1995, pp. 407 - 417.
[16] D. Hernon, E. J. Walsh, and D. M. McEligot, "Experimental Investigation into the Routes to Bypass Transition and Shear-Sheltering Phenomenon". J. Fluid Mechanics, Vol. 591, 2007, pp. 461-479.
[17] S. Becker, C. M. Stoots, K. G. Condie, F. Dursk, and D. M. McEligot, "LDA-Measurements of Transitional Flows Induced by a Square Rib", J. of Fluid Engineering, Vol. 124, Issue 1, 2002, pp. 108 - 118.
[18] W. Merzkirch, Flow Visualisation ΙΙ, New York: Academic Press, 1982.
[19] H. Schlichting, Boundary Layer Theory. 7th edition, McGraw-Hill, USA, 1979.
[20] J. C. Bhatia, F. Durst, and J. Jovanovic, "Correction of Hotwire Anemometry Measurements Near Walls". J. Fluid Mechanics, Vol. 122, 1982, pp. 411-431.
[21] J. Kim, and T. W. Simon, "Freestream Turbulence and Concave Effects on Heated, Transitional Boundary Layers". NASA CR 187150, Vol. 1, 1991.
[22] P. E. Roach, "The Generation of Nearly Isotropic Turbulence by means of Grids", Heat and Fluid Flow, Vol. 8, No. 2, 1987.