Experimental Work on Unsteady Helicopter Rotor Hub Wakes

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences
Volume 65, No. 2, January 2020, Pages 314-323

Iskandar Shah Ishak1, Shuhaimi Mansor1,*, Tholudin Mat Lazim1, Shabudin Mat1, Mohd Zarhamdy Md. Zain1, Rizal Effendy Mohd Nasir2, Zurriati Mohd Ali2
1 School of Mechanical Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia
2 Faculty of Mechanical Engineering, Universiti Teknologi MARA, Malaysia
*Corresponding author: shuhaimi@utm.my

KEYWORDS

Dynamic analysis; helicopter; tail shake; unsteady aerodynamic; wake

ABSTRACT

Helicopter tail shake phenomenon is a topic of main distress for the rotorcraft industry since it adversely affects the overall performance, occupants’ comfort and handling qualities of helicopter. This research work is intended to investigate the unsteady aerodynamic wake characteristics induced by the helicopter rotor hub that lead to this tail shake phenomenon by executing a wind tunnel campaign. The experiments were carried out in the UTM wind tunnel with a test section of 2m (width) x 1.5m (height) x 5.8m (length) with the maximum wind speed of 80m/s. Dynamic pressure measurements inside the wake due to the effect of helicopter advance ratios and pylon configurations were performed. The dynamic analysis conducted through the power spectral density and root-mean-square methods, has successfully managed to quantify the frequency and the amplitude of unsteadiness of the hub wakes that lead to the tail shake problem. The analyses tell that by employing pylon to the rotor hub, it could significantly reduce the wake unsteadiness up to 99.31%. Subsequently the findings of this research have potential to minimize this long running problem that undoubtedly could benefit the entire growing helicopter industry.

CITE THIS ARTICLE

MLA
Iskandar Shah, Ishak, et al. “Experimental Work on Unsteady Helicopter Rotor Hub Wakes.” Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 65.2 (2020): 314-323.

APA
Iskandar Shah, I., Shuhaimi, M., Tholudin, M. L., Shabudin, M., Mohd Zarhamdy, M. Z., Rizal Effendy, M. N., & Zurriati M. A.(2020). Experimental Work on Unsteady Helicopter Rotor Hub Wakes. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 65(2), 314-323.

Chicago
Iskandar Shah Ishak, Shuhaimi Mansor, Tholudin Mat Lazim, Shabudin Mat, Mohd Zarhamdy Md. Zain, Rizal Effendy Mohd Nasir, and Zurriati Mohd Ali. “Experimental Work on Unsteady Helicopter Rotor Hub Wakes.” Journal of Advanced Research in Fluid Mechanics and Thermal Sciences. 65, no. 2 (2020): 314-323.

Harvard
Iskandar Shah, I., Shuhaimi, M., Tholudin, M.L., Shabudin, M., Mohd Zarhamdy, M.Z., Rizal Effendy, M.N., and Zurriati M.A., 2020. Experimental Work on Unsteady Helicopter Rotor Hub Wakes. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 65(2), pp. 314-323.

Vancouver
Iskandar Shah I, Shuhaimi M, Tholudin ML, Shabudin M, Mohd Zarhamdy MZ, Rizal Effendy MN, Zurriati MA. Experimental Work on Unsteady Helicopter Rotor Hub Wakes. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences. 2020;65(2): 314-323.

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