Interaction of Laser Energy with Bow Shock in Mach 5 Flow

Abstract:

In order to develop a potential way to reduce the stagnation pressure and heat flux of the blunt body in hypersonic flow, single pulsed and high rated laser energy are deposited respectively to control the bow shock in Mach 5 flow. Process of the interaction of 100mJ single pulsed laser energy with bow shock is studied by schlieren experiment in Mach 5 shock tunnel. The results indicate that the schlieren photographs and stagnation pressure at different times fit well with the simulation. Bow shock is distorted by the laser induced blast wave. During a single laser pulse, the average stagnation pressure and temperature are reduced by 6.5% and 3.4%. High rated laser energy is used to sustain the low pressure and heat flux region to increase the control efficiency. With the power of 6.6% of the enthalpy flux, when the distance of deposition point and blunt body is 1.1 times of the diameter of the blunt body, the pressure and heat flux of the stagnation point is reduced to 49% and 75%, respectively. The mechanism of interaction of laser and bow shock is disclosed.

• Periodical: Applied Mechanics and Materials (Volumes 313-314)
• Pages: 596-599
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.313-314.596
• Online since: March 2013
• Authors: Dian Kai Wang, Yan Ji Hong, Jiang Bo Li
• Keywords: Flow Control, Hypersonic, Laser Interaction, Schlieren, Shock Tunnel

References

[2] dimensional RANS equations are solved and high resolved schlieren technique are used to study the interaction of laser energy with bow shock in Mach 5 flow. Mechanisms of the reduction of pressure and flux are disclosed. The results indicate that: the bow shock is distorted during the interaction of laser induced blast wave with bow shock, by which the high pressure region detaches from the blunt body. Duration of the low pressure region generated by single pulsed region is short, so the efficiency is quite low. High rate laser with 80kHz frequency is studied. With the non-dimensional L=1.1, the pressure and heat flux reduced to 49% and 75%, respectively. References

DOI: 10.1007/978-3-642-78829-1_21