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Research Papers

The Influence of an Upstream Pylon on Open Rotor Aerodynamics at Angle of Attack

[+] Author and Article Information
Nishad G. Sohoni

Whittle Laboratory,
University of Cambridge,
Cambridge CB3 0DY, UK

Cesare A. Hall

Whittle Laboratory,
University of Cambridge,
Cambridge CB3 0DY, UK
e-mail: cah1003@cam.ac.uk

Anthony B. Parry

Rolls-Royce plc,
P.O. Box 31,
Derby DE24 8BJ, UK

1Corresponding author.

Manuscript received March 6, 2018; final manuscript received July 19, 2018; published online January 16, 2019. Assoc. Editor: Coutier-Delgosha Olivier.

J. Turbomach 141(2), 021006 (Jan 16, 2019) (9 pages) Paper No: TURBO-18-1052; doi: 10.1115/1.4041082 History: Received March 06, 2018; Revised July 19, 2018

The aerodynamic impact of installing a horizontal pylon in front of a contra-rotating open rotor engine, at take-off, was studied. The unsteady interactions of the pylon's wake and potential field with the rotor blades were predicted by full-annulus URANS CFD calculations at 0 deg and 12 deg angle of attack (AoA). Two pylon configurations were studied: one where the front rotor blades move down behind the pylon (DBP), and one where they move up behind the pylon (UBP). When operating at 12 deg AoA, the UBP orientation was shown to reduce the rear rotor tip vortex sizes and separated flow regions, whereas the front rotor wake and vortex sizes were increased. In contrast, the DBP orientation was found to reduce the incidence variations onto the front rotor, leading to smaller wakes and vortices. The engine flow was also time-averaged, and the variation in work done on average midspan streamlines was shown to depend strongly on variation in incidence, along with a smaller contribution related to change of radius.

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References

Ricouard, J. , Julliard, E. , Omaïs, M. , Regnier, V. , Parry, A. B. , and Baralon, S. , 2010, “ Installation Effects on Contra-Rotating Open Rotor Noise,” AIAA Paper No. 2010-3795.
Boisard, R. , Delattre, G. , and Falissard, F. , 2014, “ Computational Fluid Dynamics as a Support to Counter-Rotating Open-Rotor Wind-Tunnel Test Analysis,” J. Aircr., 51(2), pp. 614–628. [CrossRef]
Stürmer, A. , Yin, J. , and Akkermans, R. , 2014, “ Progress in Aerodynamic and Aeroacoustic Integration of CROR Propulsion Systems,” Aeronaut. J., 118(1208), pp. 1137–1158. [CrossRef]
Colin, Y. , Wlassow, F. , Caruelle, B. , Nodé-Langlois, T. , Omaïs, M. , Spiegel, P. , and Parry, A. B. , 2014, “ Installation Effects on Contra-Rotating Open Rotor Noise at High-Speed,” AIAA Paper No. 2014-2971.
Sohoni, N. G. , Hall, C. A. , Brandvik, T. , and Parry, A. B. , 2015, “ Prediction and Measurement of Unsteady Blade Surface Pressures on an Open Rotor,” ASME Paper No. GT2015-42334.
Paquet, C. , Julliard, E. , Ricouard, J. , and Spiegel, P. , 2014, “ Z08: Low-Speed Aero-Acoustic Experimental Characterization of Open Rotor Installation on Aircraft,” AIAA Paper No. 2014-2747.
Brandvik, T. , and Pullan, G. , 2011, “ An Accelerated 3D Navier–Stokes Solver for Flows in Turbomachines,” ASME J. Turbomach., 133(2), p. 021025. [CrossRef]
Denton, J. D. , 1983, “ An Improved Time-Marching Method for Turbomachinery Flow Calculation,” ASME J. Eng. Gas Turbines Power, 105(3), pp. 514–521. [CrossRef]
Jameson, A. , 1991, “ Time Dependent Calculations Using Multigrid, With Applications to Unsteady Flows past Airfoils and Wings,” AIAA Paper No. 91-1596.
Jameson, A. , Schmidt, W. , and Turkel, E. , 1981, “ Numerical Solutions of the Euler Equations by Finite Volume Methods Using Runge-Kutta Time-Stepping Schemes,” AIAA Paper No. 81-1259.
Spalart, P. R. , and Allmaras, S. R. , 1994, “ A One-Equation Turbulence Model for Aerodynamic Flows,” Rech. Aerosp., 1, pp. 5–21.
Loring, B. , 2013, “ Line Integral Convolution in ParaView,” Kitware, Inc., New York, accessed June 6, 2016, https://web.archive.org/web/20160606023821/http://www.paraview.org/Wiki/ParaView/Line_Integral_Convolution
Cabral, B. , and Leedom, L. C. , 1993, “ Imaging Vector Fields Using Line Integral Convolution,” 20th Annual Conference on Computer Graphics and Interactive Techniques—SIGGRAPH, Anaheim, CA, Aug. 2–6, pp. 263–270.
Laramee, R. , Jobard, B. , and Hauser, H. , 2003, “ Image Space Based Visualization of Unsteady Flow on Surfaces,” IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, pp. 131–138.
Gonzalez-Martino, I. , Francois, B. , and Rodriguez, B. , 2014, “ A Numerical Insight Into Contra-Rotating Open Rotor in-Plane Loads,” Mech. Ind., 15(1), pp. 19–28. [CrossRef]
Zachariadis, A. , Hall, C. A. , and Parry, A. B. , 2013, “ Contrarotating Open Rotor Operation for Improved Aerodynamics and Noise at Takeoff,” ASME J. Turbomach., 135(3), p. 031010. [CrossRef]

Figures

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Fig. 1

Definition of AoA; and pylon orientation relative to front rotor rotation: DBP and UBP

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Fig. 2

Computational domains for simulation and postprocessing: (a) computational domain showing pylon, rotors, and block boundaries and (b) relative domains and radial clustering of absolute-frame mesh

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Fig. 3

Engine performance parameters

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Fig. 4

Variation of CT and CP around the annulus

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Fig. 5

Contours of time-averaged flow: (a) front rotor inlet αloc and (b) rear rotor inlet whirl, at 12 deg AoA

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Fig. 6

Contours of time-averaged entropy function at (a) front rotor exit, and (b) rear rotor exit, at 12 deg AoA

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Fig. 7

Contours of instantaneous entropy function at rotor exits, and virtual tufts on rotor suction surface, colored by Vx, at 12 deg AoA. Flow is into the page.

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Fig. 8

Front rotor tip vortex characterization: (a) radial and axial variation of front rotor tip vortex cores. Cuts for all cases were made at the same axial locations, at 12 deg AoA, but are staggered for clarity. Rear rotor stagger change axis is marked and (b) circumferential variation of (b1) radial location of vortex core, and (b2) vortex circulation, at x′ 0:14DF, for 12 deg AoA.

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Fig. 9

Annular variation of incidence, inlet Mach number, and ζ at midspan: (a) front rotor mid-span and (b) rear rotor mid-span

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Fig. 10

Work and incidence on time-averaged streamlines, at 12 deg AoA: (a) streamlines at front rotor mid-span and (b) streamlines at rear rotor mid-span

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Fig. 11

Effect of change of radius on front rotor work: (a) components of front rotor work and (b) annular variation of Δθ (solid lines) and Δr (dashed lines), front rotor mid-span

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Fig. 12

Effect of change of radius on rear rotor work: (a) components of rear rotor work and (b) annular variation of Δθ (solid lines) and Δr (dashed lines), rearrotor mid-span

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Fig. 13

Fast Fourier transform of static pressure at front rotor midspan for 0 deg and 12 deg AoA, r/RF = 0.75, x/c = 0.1

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Fig. 14

Fast Fourier transform of static pressure at rear rotor midspan for 0 deg and 12 deg AoA, r/RR = 0.75, x/c = 0.1

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