Determination of the Principal Directions of Composite Helicopter Rotor Blades with Arbitrary Cross Sections

  • Published : 2000.03.01

Abstract

Modern helicopter rotor blades with non-homogeneous cross sections, composed of anisotropic material, require highly sophisticated structural analysis because of various cross sectional geometry and material properties. They may be subjected by the combined axial, bending, and torsional loading, and the dynamic and static behaviors of rotor blades are seriously influenced by the structural coupling under rotating condition. To simplify the analysis procedure using one dimensional beam model, it is necessary to determine the principal coordinate of the rotor blade. In this study, a method for the determination of the principal coordinate including elastic and shear centers is presented, based upon continuum mechanics. The scheme is verified by comparing the results with confirmed experimental results.

Keywords

References

  1. Bauchau, O. A., and Hong, C., 1987, 'Finite-Element Approach to Rotor Blade Modeling,' Journal of the American Helicopter Society, pp. 60-67
  2. Chandra, R., and Chopra, I., 1992, 'Experimental- Theoretical Investigation of the Vibration Characteristics of Rotating Composite Box Beams,' Journal of Aircraft, Vol. 29, No.4, pp. 657-664
  3. Giavotto, V., Borri, M., Mantegazza, P., and Ghiringhelli, G., 1983, 'Anisotropy Beam Theory and Applications,' Computer & Structures, Vol. 16, No. 14, pp. 403-413 https://doi.org/10.1016/0045-7949(83)90179-7
  4. Hodges, D. H., 1979, 'An Aeromechanical Stability Analysis for Bearingless helicopter Rotor Blades,' Journal of the American Helicopter Society, Vol. 114, pp. 57-73
  5. Hodges, D. H., 1990, 'Review of Composite Rotor Blade Modeling,' AIAA Journal, pp. 561 -565
  6. Joo, J., 1993, 'An Experimental Study on the Dynamic Characteristics of a Hingeless Rotor in Hover,' Ph. D. Dissertation, Dept. of Aerospace Engineering, Seoul National University
  7. Jung, S. N., and Kim, S. J., 1996, 'Transverse Shear Behavior on the Aeroelastic Stability of Composite Rotor Blades,' KSME Journal, Vol. 10, No.1, pp. 12-21
  8. Jung, S. N., 1993, 'Finite Element Analysis in the Aeroelastic Stability of Composite Helicopter Rotor Blades,' Ph. D. Dissertation, Dept. of Aerospace Engineering, Seoul National University
  9. Kardestuncer, H., and Norrie, D. H., 1987, Finite Element Handbook, McGraw-Hill, pp. 4.183-4.189
  10. Pinkey, R. L., 1974, 'Helicopter Rotor Blade, Application of Composite Materials,' ASTM STP 524, pp. 57-60
  11. Rapp, H., and Wondle, R., 1992, 'Influence of Cross Section Variation on Structural Behavior of Composite Rotor Blades,' 48th Annual Forum of the American Helicopter Society, Washington D. C., pp. 3-10
  12. Wondle, R., 1982, 'Calculation of the Cross Section Properties and the Shear Stress of Composite Rotor Blades,' Vertica, Vol. 6, pp. 111-129
  13. Yoo, H. H., Pierre, C., and Ryan, R. R., 1997, 'A New Formulation for the Torsional vibration Analysis of Rotating Cantilever rods,' KSME International Journal, Vol. 11, No.2, pp. 143 -154
  14. Yu, Y., Chung, K., and Oh, T., 1995, 'Determination on the Cross Sectional Properties of Composite Rotor Blade,' Proceedings of the KSME Spring Annual Meeting '95, pp. 354-359
  15. Yu, Y., Oh, T., and Choi, M., 1996, 'Effect of Ply Angle on the Cross Sectional Properties of Composite Rotor Blade,' Proceedings of Asian Pacific Conference for Fracture and Strength' 96, pp. 621-624