Momentum transfer and plasma formation above a surface with a high-power CO2 laser

Abstract

An experiment was performed to measure the total impulse transferred to a surface by a high-power pulsed 10.6-μ laser under atmospheric conditions, and also to determine the degree to which the observed plasma decouples the laser energy from the surface. Specific interest was directed toward conditions under which a ``radiation-driven detonation wave'' may form due to the presence of a surface. The momentum transferred in dyn sec/J decreases with an increase in the ratio of incident energy to spot area since a larger fraction of the energy is decoupled from the surface.

Momentum Transfer in a Surface with a Pulsed Laser

“…With more extensive data since the work of Ref. 3 In this expression, the bluntness ratio, B, and freestrearn Mach number are seen to weight the effective Mach number closer to the sharp cone surface value, M s , or the blunt cone surface value, M B , than a simple average. Physically, the expression may be explained with the aid of Fig.…”

State of the art in micro forming

“…Non-thermal laser forming is a fairly new process, which uses the optical low-threshold surface breakdown [17,18] and results in creation of a shock wave [19]. The laser induced shock wave can in principle be used for all micro sheet metal forming processes.…”

Laser Ablation Thrusters for Atmospheric Flight Applications

“…In an atmosphere, the physics of the initial interaction between a high-power laser beam and a surface is strongly influenced by the presence of air above the surface. Before a jet of absorbing vapor can be obtained, the air above the surface may break down, and a lasersupported detonation wave will be initiated 3,4 .…”