Transient helicopter rotor wakes in response to time-dependent blade pitch inputs

Journal of Aircraft

Volumn 41, Issue 5, 2004, Pages 1025-1041

  Ananthan, Shreyas ^a,b   Leishman, J Gordon ^a,b  

^a UNIVERSITY OF MARYLAND   (United States)

^b UNIVERSITY OF MARYLAND   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

AERODYNAMICS; DIFFUSION; KINEMATICS; MATHEMATICAL MODELS; NAVIER STOKES EQUATIONS; STRAIN; TIME VARYING SYSTEMS; TURBULENCE; VISCOSITY;

HELMHOLTZ'S SECOND LAW STATES; KINEMATIC VISCOSITY; ROTOR AERODYNAMICS; ROTOR AIRLOADS;

HELICOPTER ROTORS;

EID: 7544232850     PISSN: 00218669     EISSN: 15333868     Source Type: Journal    
DOI: 10.2514/1.3561     Document Type: Article

References (31)

1. Leishman, J. G., Principles of Helicopter Aerodynamics, Cambridge Univ. Press, New York, 2000, Chap. 1.
2. Schnritz, E H., "Rotor Noise," Aeraacoustics if Flight Vehicles: Theory and Practice, edited by H. H. Hubbard, Vol. 1, NASA Reference Publication 1258, Washington, DC, Aug. 1991, Chap. 2.
3. Leishman, J. G., and Bagi, A., "Challenges hi Understanding the Vortex Dynamics of Helicopter Rotor Wakes," AIM Journal, Vol. 36, No. 7, 1998, pp. 1130-1140.
4. Martin, P. B., Pugliese, G., and Leishman, J. G., "High Resolution 'Bailing Vortex Measurements in the Wake of a Hovering Rotor," Proceedings of the American Helicopter Society 57th Aimual National forum, American Helicopter Society, Alexandria, VA, 2001.
5. Leistanan, J. G., Bhagwat, M., and Bagai, A., "Free-Vortex Methods for Helicopter Rotor Wake Analyses," Journal of Aircraft, Special Ed. on Rotorcraft Wakes, Vol. 39, No. 5, 2002, pp. 759-775.
6. Theodore, C., and Celi, R., "Flight Dynamic Simulation of Hingdess Rowr Helicopters Including a Manemring Free Wake Model," Proceedings of the American Helicopter Society 54th Annual National Forum, American Helicopter Society, Alexandria, VA, 1998.
7. Bagai, A., Leishman, J. G., and Park, J., "Aerodynamic Analysis of a Helicopter in Steady Maneuvering Flight Using a Free-Vortex Rotor Wake Model," Journal of the American Helicopter Society, Vol. 44 No. 2, 1999, pp. 109-120.
8. Quackenbush, T. R., Seller, J. D., Wachspress, D. A., and Boscntrseh, A. H., "Reduced Order Free Wake Modeling for Near Real Time Simulation of Rotorcraft Flight Mechanics" Proceedings of the American Helicopter Society 55th Annual National Forum, American Helicopter Society, Alexandria, VA, May 1999.
9. Barocela, E., Peters, D. A., Krothapaffi, K. R., and Prasad, J. V. R., "The Effect of Wake Distortion on Rotor Inflow Gradients and Off-Axis Coupling," AIAA-97-3579, 1997.
10. Keller, J. D., and Cnrtiss, H. C., "Modeling the Induced Velocity of a Maneuvering Helicopter," Proceedings of the American Helicopter Society 52nd Annual National Forum, American Helicopter Society, Alexandria, VA, 1996.
11. Rosen, A., and Isser, A., "A New Model of Rotor Dynamics During Pitch and Roll of a Hovering Helicopter," Journal ofthe American Helicopter Society, Vol. 30, No. 3, 1995, pp. 17-28.
12. Taylor, M. K., "A Balsa-Dust Technique for Air-Flow Visualization and Its Application to Flow Through Model Helicopter Rotors in Static Thrmst." NACA TN-2220, Nov. 1950.
13. Saffman, P. G., Vortex Dynamics, Cambridge Univ. Press, Cambridge, England, U.K., 1992.
14. Carpenter, P. J., and Friedovich, B., "Effect of A Rapid Blade-Pitch Increase on the Thrust and Induced-Velocity Response of a Full-Scale Helicopter Rotor," NACA TN 3044, Nov. 1953.
15. Jessurun, K. P., Pavel, M. D., and Toet, S., "Apparent Mass Effects on a Stiff-Hinged Rotor Model After Raid Cyclic and/or Collective Inputs-A Flow Visualization Study," Proceedings of the European Rotorcraft Forum, Moscow, Sept. 2001.
16. Tang, L., and Baeder, J. D., "Improved Euler Simulation of Hovering Rotor Tip Vortices with Validation," Proceedings of the American Helicopter Society 5th Annual Forum, American Helicopter Society, Alexandria, VA, 1999.
17. Bhagwat, M. J., and Leishman, J. G., "Time-Accurate Modeling of Rotor Wakes Using a Free-Vortex Wake Method," AIAA-2000-4120, 2000.
18. Bhagwat, M. J., and Leishman, J. G., "Stability, Consistency and Convergence of Time-Marching Free-Vortex Rotor Wake Algorithms," Journal of the American Helicopter Society, Vol. 46, No. 1, 2001, pp. 59-71.
19. Ananthan, S., Leishman, J. G., and Ramasamy, M., 'The Role of Filament Stretching in the Free-Vortex Modeling of Rotor Wakes," Proceedings of the American Helicopter Society 58th Annual Forum, American Helicopter Society, Alexandria, VA, 2002.
20. Bhagwat, M. J., and Leishman, J. G., "Generalized Viscous Vortex Core Models for Application to Free-Vortex Wake and Aeroacoustic Calculations," Proceedings of the American Helicopter Society 58th Annual Forum, American Helicopter Society, Alexandria, VA, 2002.
21. Ramasamy, M., and Leishman, J. G., "The Interdependence of Straining and Viscous Diffusion Effects on Vorticity in Rotor Flow Fields, " Proceedings of the American Helicopter Society 59th Annual Forum, American Helicopter Society, Alexandria, VA, 2003.
22. Rossow, V. J., "Convective Merging of Vortex Cores in Lift-Generated Wakes," Journal of Aircraft, Vol. 14, No. 3, 1977, pp. 283-290.
23. Johnson, W., Helicopter Theory, Princeton Univ. Press, NJ, 1980, Chap. 9.
24. Bhagwat, M. J., and Leishman, J. G., "Stability Analysis of Helicopter Rotor Wakes in Axial Flight," Journal of the American Helicopter Society, Vol. 45, No. 3, 2000, pp. 165-178.
25. Ormiston, R. A., and Peters, D. A., "Hingeless Rotor Response with Nonuniform Inflow and Elastic Blade Bending," Journal of Aircraft, Vol. 9, No. 10, 1972, pp. 730-736.
26. Gaonkar, G. H., and Peters, D. A., "Effectiveness of Current Dynamic Inflow Models in Hover and Forward Flight," Journal of the American Helicopter Society, Vol. 31, No. 2, 1986, pp. 47-57.
27. Ellenrieder, T. J., and Brinson, P. R., "The Dynamic Induced Velocity Field of a Model Rotor in Hover Conditions," The Aeronautical Journal, Vol. 102, June/July 1998, pp. 331-335.
28. Drees, J. M., andHendal, W. P., "The Field of Flow Through a Helicopter Rotor Obtained from Wind Tunnel Smoke Tests," Versl. Nat. Luchtvlab, Rept. A. 1205, Feb. 1950; also Journal of Aircraft Engineering, Vol. 23, No. 266, April 1951, pp. 107-111.
29. Drees, J. M., andHendal, W. P., "The Field of Flow Through a Helicopter Rotor Obtained from Wind Tunnel Smoke Tests," Versl. Nat. Luchtvlab, Rept. A. 1205, Feb. 1950; also Journal of Aircraft Engineering, Vol. 23, No. 266, April 1951, pp. 107-111.
30. Leishman, J. G., Bhagwat, M. I, and Ananthan, S, "Predictions of the Vortex Ring State for Single-Rotor and Multi-Rotor Configurations," Proceedings of the American Helicopter Society 58th Annual Forum, American Helicopter Society, Alexandria, VA, 2002.
31. JanakiRam, R. D., and Khan, H., "Prediction and Validation of Helicopter Descent Flyover Noise," Proceedings of the American Helicopter Society 56th Annual Forum, American Helicopter Society, Alexandria, VA, 2000.