Consolidated Laser-Induced Fluorescence Diagnostic Systems for the NASA Ames Arc Jet Facilities

Abstract

The spectroscopic diagnostic technique of two photon absorption laser-induced fluorescence (TALIF) of atomic species for non-intrusive arc jet flow property measurement was first implemented at NASA Ames in the mid-1990s. Use of TALIF expanded at NASA Ames and to NASA Johnson's arc jet facility in the late 2000s. In 2013-2014, NASA combined the agency's large-scale arc jet test capabilities at NASA Ames. Concurrent with that effort, the agency also sponsored a project to establish two comprehensive LIF diagnostic systems for the Aerodynamic Heating Facility (AHF) and Interaction Heating Facility (IHF) arc jets. The scope of the project enabled further engineering development of the existing IHF LIF system as well as the complete reconstruction of the original AHF LIF system. The updated LIF systems are identical in design and capability. They represent the culmination of over 20 years of development experience in transitioning a specialized laboratory research tool into a measurement system for large-scale, high-demand test facilities. This paper documents the overall system design from measurement requirements to implementation. Representative data from the redeveloped AHF and IHF LIF systems are also presented.

WITHDRAWN: Visualization of Görtler vortices in high–enthalpy plasma flow using planar laser-induced fluorescence

“…Simulating these conditions in a quiet wind tunnel becomes challenging [20]. Therefore, to simulate entry conditions into the atmosphere, various facilities have been developed, including inductively coupled plasma wind tunnel, [21,22] arc-heated wind tunnel, [23][24][25] and others. The arc-heated wind tunnel has become one of the most excellent facilities for generating high-enthalpy non-equilibrium flow due to its high flux density as well as its high particle speed, high temperature and large flow area [26,27].…”