Interaction of an optical pulsed discharge with a gas: conditions for stable generation and merging of shock waves

Theoretical and Experimental Investigations of Lightcraft/ Impulsar Related Problems

“…Works on refinement of scientific, engineering and technological solutions with respect to GDL were not discontinued till today. The transformation of pulsed periodic laser radiation into a quasistationary wave (QSW) under the conditions of an optical pulsating discharge (OPD) for the case of lightcraft engine was studied for the first time in our publications [1,2].…”

'Impulsar': New Application for High Power High Repetition Rate Pulse-Periodic Lasers

“…It was pointed out in papers [26] that the LAJE can find applications for launching space crafts if ~ 100-kJ repetitively pulsed lasers with pulse repetition rates of hundreds hertz are developed and the damage of the optical reflector under the action of shock waves and laser plasma is eliminated. These problems can be solved by using high pulse repetition rates (f~ 100 kHz), an optical pulsed discharge, and the merging of shock waves [12,13]. The efficiency of the use of laser radiation in the case of short pulses at high pulse repetition rates is considerably higher.…”

“…The third parameter can be determined from expression (6). The conditions l/f~t a and ∆ ≈ 1 -2 correspond to the merging of shock waves [12]. The important parameters are the ratio of t a to the propagation time t z = L/C m of sound over the entire rocket length L (C m is the sound speed in a metal) and the ratio of t z to 1/f.…”

“…For steel and aluminum, C m = 5.1 and 5.2 km s -1 , respectively. By using (10), we obtain: (12) Here, L is measured in cm and C m in cm s -1 . Expression (12) gives the energy:…”

“…Scheme of the experiment, side (a) and front (b) view: (1) OPD; (2) argon jet; (3) replaceable cylindrical attachment (reflector); (4) high-pressure chamber (rocket model); (5) elastic hose for argon supply; (6) model suspension wires; (7) laser radiation; (8) focusing lens; (9) block; (10) wire connecting cylinder (3) with weight (11); (12) balance; (13) shockwave pressure gauge.…”