Mach Number Effect on Supersonic Drag Reduction using Repetitive Laser Energy Depositions over a Blunt Body

作者：Iwakawa Akira^*; Shoda Tatsuro; Majima Ryosuke; Pham Son Hoang; Sasoh Akihiro

来源：Transactions of the Japan Society for Aeronautical and Space Sciences, 2017, 60(5): 303-311.

DOI：10.2322/tjsass.60.303

• Aerodynamics
• Shock-waves
• Wind Tunnel Testing
• Drag Reduction
• Energy Deposition

Supersonic drag reduction performance using repetitive pulse energy depositions over blunt bodies was experimentally studied under two Mach numbers. The normalized drag reduction and energy deposition efficiency of Mach-1.92 over a 10-mm-dia. blunt-cylinder model were 8% and 1.2 at most, respectively. On the other hand, these values at Mach-3.20 over the same model were 22% and 6.2, respectively. The shock-wave deformation period using single-pulse energy deposition at Mach-3.20 was 64 mu s. This duration was shorter than that of 80 mu s at Mach-1.92, but the deformation magnitude on the model center axis of 40% at Mach-3.20 was larger than that of 15% at Mach-1.92. These experimental characteristics were consistent as solutions of the Riemann problem. Moreover, a drag reduction performance was much improved with a larger model diameter of 20 mm. Therefore, it has been experimentally demonstrated that the drag reduction performance due to energy deposition improves much at a high Mach number and with large model dimensions.

• 出版日期2017