Combined Surface Heating by Laser Beam and Subsonic Nitrogen Plasma Jet

Abstract

The paper describes new combined heating capability of the IPMech RAS inductively coupled plasma facility VGU-4. A 200 W ytterbium laser was added to the facility as a source of radiative heating. The cylindrical specimen made of the Buran orbital vehicle’s heat-shielding tile material with a black low catalytic coating was exposed to subsonic pure nitrogen plasma jet and laser radiation. The specimen surface temperature reached 1325 ∘C during combined radiative and convective heating. The maximum heat flux obtained in the combined mode for a laser incident power of 47 W and a VGU-4 HF-generator anode power of 22 kW was 32.1 W/cm2. The convective heat flux from the nitrogen plasma jet at the same anode power was 12.6 W/cm2. Adding a laser to an existing inductively coupled plasma facility gives the future opportunity to better simulate entry into the atmospheres of Mars, Venus, the outer planets and their moons.

Keywords

• induction HF-plasmatron
• pulsed fiber laser
• heat transfer
• plasma
• high-enthalpy gas flow
• combined heating