A combined experimental and numerical program was carried out to improve the flow uniformity and periodicity in the NASA transonic flutter cascade. The objectives of the program were to improve the periodicity of the cascade and to resolve discrepancies between measured and computed flow incidence angles and exit pressures. Previous experimental data and some of the discrepancies with computations are discussed. In the present work surface pressure taps, boundary layer probes, shadowgraphs, and pressure-sensitive paints were used to measure the effects of boundary layer bleed and tailboard settings on flowfield periodicity. These measurements are described in detail. Two numerical methods were used to analyze the cascade. A multibody panel code was used to analyze the entire cascade and a quasi-three-dimensional viscous code was used to analyze the isolated blades. The codes are described and the results are compared to the measurements. The measurements and computations both showed that the operation of the cascade was heavily dependent on the endwall configuration. The endwalls were redesigned to approximate the midpassage streamlines predicted using the viscous code, and the measurements were repeated. The results of the program were that: (1) Boundary layer bleed does not improve the cascade flow periodicity. (2) Tunnel endwalls must be shaped like predicted cascade streamlines. (3) The actual flow incidence must be measured for each cascade configuration rather than using the tunnel geometry. (4) The redesigned cascade exhibits excellent periodicity over six of the nine blades.

1.
Buffum
,
D. H.
,
Capece
,
V. R.
,
King
,
A. J.
, and
El-Aini
,
Y. M.
,
1998
, “
Oscillating Cascade Aerodynamics at Large Mean Incidence
,”
ASME J. Turbomach.
,
120
, pp.
122
130
;
2.
also NASA TM-107247.
1.
Buffum, D. H., Capece, V. R., King, A. J., and El-Aini, Y. M., 1996, “Experimental Investigation of Unsteady Flows at Large Incidence Angles in a Linear Oscillating Cascade,” AIAA Paper No. 96-2823;
2.
also NASA TM-107283.
1.
Lepicovsky, J., McFarland, E. R., Chima, R. V., and Wood, J. R., “On Flowfield Periodicity in the NASA Transonic Flutter Cascade: Part I—Experimental Study,” ASME Paper No. 2000-GT-572.
2.
Chima, R. V., McFarland, E. R., Wood, J. R., and Lepicovsky, J., 2000, “On Flowfield Periodicity in the NASA Transonic Flutter Cascade: Part II—Numerical Study,” ASME Paper No. 2000-GT-573.
3.
Boldman, D. R., and Buggele, A. E., 1978, “Wind Tunnel Tests of a Blade Subjected to Midchord Torsional Oscillations at High Subsonic Stall Flutter Conditions,” NASA TM-78998.
4.
Shaw
,
L. M.
,
Boldman
,
D. R.
,
Buggele
,
A. E.
, and
Buffum
,
D. H.
,
1986
, “
Unsteady Pressure Measurements on a Biconvex Airfoil in a Transonic Oscillating Cascade
,”
ASME J. Eng. Gas Turbines Power
,
108
, pp.
53
59
.
5.
Buffum, D. H., and Fleeter, S., 1991, “Wind Tunnel Wall Effects in a Linear Oscillating Cascade,” NASA TM-103690.
6.
Buffum, D. H., and Fleeter, S., 1988, “Investigation of Oscillating Cascade Aerodynamics by an Experimental Influence Coefficient Technique,” NASA TM-101313.
7.
Ott, P., Norryd, M., and Bo¨lcs, A., 1998, “The Influence of Tailboards on Unsteady Measurements in a Linear Cascade,” ASME Paper No. 98-GT-572.
8.
Boldman, D. R., and Buggele, A. E., 1983, “Experimental Evaluation of Shockless Supercritical Airfoils in Cascade,” AIAA Paper No. 83-0003.
9.
Bencic, T. J., 1995, “Experience Using Pressure Sensitive Paint in NASA Lewis Research Center Propulsion Test Facilities,” AIAA Paper No. 95-2831.
10.
Lepicovsky, J., Bencic, T. C., and Bruckner, R. J., 1997, “Application of Pressure Sensitive Paint to Confined Flow at Mach Number 2.5,” AIAA Paper No. 97-3214.
11.
McFarland, E. R., 1993, “An Integral Equation Solution for Multistage Turbomachinery Design Calculations,” ASME Paper No. 93-GT-41.
12.
McFarland, E. R., 1994, “Use of Preliminary Design Methods in the Analysis of Multi-Stage Turbomachinery,” NASA CP 3282, Vol. 2.
13.
Chima
,
R. V.
,
1987
, “
Explicit Multigrid Algorithm for Quasi-Three-Dimensional Viscous Flows in Turbomachinery
,”
J. Propul. Power
,
3
, No.
5
, pp.
397
405
.
14.
Chima, R. V., 1995, “A k-ω Turbulence Model for Quasi-Three-Dimensional Turbomachinery Flows,” AIAA Paper No. 96-0248; also NASA TM-107051.
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