Test cases

Test case 11.1
Wall-mounted two-dimensional hump with oscillatory zero-mass-flux jet or suction through a slot

This is a carry-over test case from the recent (March 2004) NASA Langley workshop. Experimental data are available for three cases: the baseline without any control, the flow with steady suction, and the flow with a zero-efflux oscillatory slot jet.

This test case has been considered as the best defined of all three cases considered at the NASA Workshop. It is nominally two-dimensional, although the end plates bring some 3D effects. The hump is 420 mm long with the crest of 53.7 mm and is mounted on a splitter plate of thickness 12.7 mm, which extends 1935 mm upstream from the hump leading edge and 1129 mm downstream from the hump leading edge. The hump with the splitter plate are placed in a wind tunnel of 771 mm width and 508 mm height, but the nominal test section height (between the splitter plate and the top wall) is 382 mm and the nominal hump width (between the two end plates) is 584 mm. The characteristic Reynolds number based on the hump length, is about 10⁶ and the Mach number is 0.1. Results containing base plate pressure and friction factor, and PIV of mean U and V velocity components and of the uu, vv and uv stress components are available at different stations for the three cases: Baseline results (no control), suction control (steady suction rate through the slot of 0.01518 kg/s at Re=929000) and zero-efflux oscillatory forcing trough the slot, with nominal peak velocity of 26.6 m/s and frequency of 138.5 Hz (other cases are also available).

References:
Greenblatt, D., Paschal, K. B., Schaeffler, N. W., Washburn, A. E., Harris, J., and Yao, C. S., ”A Separation Control CFD Validation Test Case. Part 1: Baseline and Steady Suction”, AIAA Paper 2004-2220, June-July 2004.
Naughton, J., Viken, S., and Greenblatt, D., ”Wall Shear Stress Measurements on the NASA Hump Model for CFD Validation”, AIAA -2004-2607, 24th AIAA Aerodynamic Measurment Technology and Ground Testing Conference, Portand, OR, June 28 - July 1, 2004.
Rumsey, C. L., Gatski, T. B., Sellers III, W. L.,Vatsa, V. N., Viken, S. A., ”Summary of the 2004 CFD Validation Workshop on Synthetic Jets and Turbulent Separation Control”, AIAA Paper 2004-2217, 2nd AIAA Flow Control Conference, June 28 - July 1, 2004, Portland, OR.
Greenblatt, D., Paschal, K.B., Yao, C-S., Harris, J., ”A Separation Control CFD Validation Test Case Part 2. Zero Efflux Oscillatory Blowing”, 43rd AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, 10-13 Jan. 2005.

Contact person:
David Greenblatt, fn.d.greenblatt@larc.nasa.gov, phone: +1 757 864 8394

Detailed case description and experimental database:
http://cfdval2004.larc.nasa.gov/case3.html
Zero_Efflux_Paper_AIAA_Meeting_Reno_2005.pdf


Test case 11.2
Flow over an axisymmetric three-dimensional hill

Detailed three-component LDA measurements of velocity, surface mean pressure, oil-flow visualization in a flow field with challenging three-dimensional separation. The flow has served as a test case in the EU project FLOMANIA. LES based computations are also in progress.

References:
Simpson, R.L, Long, C.H., Byun, G.: ”Study of vortical separation from an axisymmetric hill”, Int. J. Heat and Fluid Flow, 23(5) 582-591, 2002.

Contact person:
L. Davidson, lada@tfd.chalmers.se, phone: +46 31 772 1404

You may also contact:
M. Leschzinger, mike.leschziner@imperial.ac.uk, phone: +44 207 594 5061

and the originator of the data:
R. Simpson, simpson@aoe.vt.edu, phone: +1 (540) 231-5989

Detailed case description and experimental database:
The case is described in the paper by Simpson, Long, and Byun referenced above.

The experimental data are most easily found on
http://www.tfd.chalmers.se/~gujo/WS11_2005/3D_Hill
For a description of the data format, see the info.txt document.

The data may also be sought on the originators web site (Case1). However, this web site does not open on all browsers.
http://www.aoe.vt.edu/~gbyun/

Mesh and previous results


Test case 11.3
Slanted jets in cross-flow

In a full coverage film cooling experiment a large number of jets were injected from a side wall into a main stream parallel to the wall. Measurements were performed on one of the jets located in the third row of cooling jets.
The measurements were done in about 35 000 points using a three-component laser-Doppler anemometer. In every point 5000 samples were collected. The LDA-system worked in hardware coincidence mode, i.e. all three velocity component were sampled simultaneously. Results are reported for all three mean velocity components, all Reynolds stresses, and all third order moments. The measurement volume of the LDA was nearly spherical in shape with a diameter of 45 µm (side-scatter mode). 

References:
Gustafsson, K. M. Bernhard, ”Experimental Studies of Effusion Cooling”, PhD Thesis, Department of Thermo and Fluid Dynamics, Chalmers University of Technology, SE-41296 Göteborg, Sweden. Available as pdf file here (15.9 MB).
Gustafsson, K. M. B., and Johansson, G. ”Turbulence and Velocity Fields of Slanted Jets in Crossflow - Measurements and CFD Simulations”, Turbulence, Heat and Mass Transfer 4, Oct 12-17, 2003, Antalya, Turkey.

Contact persons:
B. Gustafsson, bernhard.gustafsson@volvo.com, phone: +46 520 94955
T.G. Johansson, gujo@tfd.chalmers.se, phone: +46 31 772 1410

Detailed case description and experimental database:
http://www.tfd.chalmers.se/~gujo/WS11_2005/Slanted_jet/INDEX.HTM


Test case 11.4
Multiple-impinging jets: flow and heat transfer

PIV measurements of mean flow and turbulent second-moments, plus surface temperature and heat transfer for two jet array configurations available from Delft University of Technology.

The first case (mandatory) consists of 9 jets in an in-line arrangement. Only a quarter of the domain (90 deg sector) can be computed utilizing symmetry. RANS computations for this case have been reported by L. Thielen, K. Hanjalik, H. J.J, Jonker, and R. Manceau, ”Predictions of flow and heat transfer in multiple-impinging jets with an elliptic-blending second-moment closure”, Proc CHT-04, ICHMT International Symposium on Advances in Computational Heat Transfer, Norway, April, 2004.

The second case (optional) consists of 13 nozzles in a hexagonal arrangement. Both cases are characterized by full three-dimensionality, high anisotropy, and strong variation of heat transfer over the impingment plate.

References:

Geers LFG, Hanjalic K, Tummers MJ, "Wall imprint of turbulent structures and heat transfer in multiple impinging jet arrays," JOURNAL OF FLUID MECHANICS 546: 255-284 JAN 10 2006

Geers LFG, Tummers MJ, Hanjalic K, "Particle imaging velocimetry-based identification of coherent structures in normally impinging multiple jets," PHYSICS OF FLUIDS 17 (5): Art. No. 055105 MAY 2005

Geers LFG, Tummers MJ, Hanjalic K, "Experimental investigation of impinging jet arrays," EXPERIMENTS IN FLUIDS 36 (6): 946-958 JUN 2004
Contact person:
M. J. Tummers, mark@ws.tn.tudelft.nl, phone: +31 15 278 2477

Detailed case description and experimental database:
http://www.ercoftac.nl/workshop11/case11.4.html