Numerical and Experimental Study of the Flow Field Behind a Permeable Parachute by a Five-hole Probe

Fakhri Etemadi ； Ramin Kamali Moghaddam ； Mahmoud Mani

《Journal of Aeronautics, Astronautics and Aviation》 53卷2期 Vol.53 No.2 ISSA 2020 Special Issue (2021/06) Pp. 201-216

https://doi.org/10.6125/JoAAA.202106_53(2).12

摘要

In this study, a five-hole probe was used for the complex three-dimensional flow field behind a parachute model. The five-hole probe was calibrated in a wind tunnel by employing the structured Bayesian neural network method. According to the calibration, for the conical probe angle of 0~30 degrees, the accuracy of pitch and yaw angles were found to be around ±0.45 and ±0.9 degrees, respectively. For conical angles higher than 30 degrees, the accuracy of pitch and yaw angles were measured to be around ±2.5 degrees. At the next step, the velocity, pressure and other characteristics of the flow field measurements at two middle and side planes were performed at different distances from the parachute model and for velocities of 15 and 20 m/s. Lastly, the experimental results were compared with the numerical simulations that were obtained through Fluent software with the assumption of parachute permeability. Moreover, the supporting bar effect on the experimental results was studied by comparing the numerical results. The results revealed that a pair of large counterclockwise vortices and a pair of secondary clockwise vortices were induced behind the parachute. Compared to the numerical simulations, the presence of a supporting bar weakens the secondary vortices in the side plane.

關鍵字

Hemispherical parachute ； Wind tunnel ； Five-hole probe ； Calibration ； Flow field characteristics

參考文獻

Cruz J, Mineck R, Keller D, Bobskill M, "Wind Tunnel Testing of Various Disk-Gap-Band Parachutes," 17th AIAA Aerodynamic Decelerator Systems Technology Conference and Seminar, AIAA 2003-2129, Monterey, California,2003.

Witkowski A, Kandis M, "Comparison of subscale versus full scale wind tunnel tests of MSL disk gap band parachutes," 20th AIAA Aerodynamic Decelerator Systems Technology Conference and Seminar, AIAA 2009-2914, Seattle, Washington, 2009.

Johari H, Levshin A, "Interaction of a line vortex with a round parachute canopy," Journal of Fluids and Structures, Vol. 25, No. 8, 2009, pp. 1258–1271.

Fingersh L, Robinson M, "Wind tunnel calibration of 5-hole pressure probes for application to wind turbines," 35th AIAA, Aerospace Sciences Meeting and Exhibit, Reno, Nevada, January 1997.

Kim SH, Kang YJ, Myong RS, Cho TH, Park YM, Choi IH, "Calibration of a Five-Hole Multi-Function Probe for Helicopter Air Data Sensors," International Journal of Aeronautical and Space Sciences, Vol. 10, No. 2, 2009, pp. 43-51.