Laser Induced Fluorescence in High Enthalpy Facilities in the Tsniimach Center (Moscow Russia)

Abstract

The requirements for accurate measurements, the higher sophistication in the design, the need for monitoring, control and diagnostics in difficult circumstances and the request for data bases to validate numerical codes have incited the advanced measurement techniques to the investigation of ground test facilities. This lecture presents an experimental work and the results obtained by Laser Induced Fluorescence (LIF) in continuous high enthalpy supersonic airflow. The test campaign is performed at the Central Research Institute of Machine Building (Tsniimach, Moscow region) in ground experimental facilities designed for aerodynamics and heat transfer studies of supersonic and hypersonic aircrafts. The main objective of this test campaign was to perform measurements of species concentrations, temperature and velocity in the incoming flow, and in the boundary and shock layers over a Thermal Protection System (TPS) model simulating a misalignment of tiles, by means of techniques developed by the plasma team from the University of Rouen. So, an original method using LIF diagnostic has been implemented to measure simultaneously the three parameters. Fluorescence of NO was induced in the high enthalpy air plasma flow by a tunable ArF-excimer laser via the epsilonband system D2Sigma(+)(v1=0 <-x2Pi(v11=1) Measurements of the rotational temperature and NO number density have been performed. The spatial resolution of the LIF technique permitted accurate characterization of the boundary and shock layer, as well as shock thickness. Finally, flow velocity is deduced from the Doppler-shift measurements of excited rovibrational NOepsilon band. Analysis of me results will allow to assess the validity of the computational tools in order to control the representativity of future industrial tests devoted to local aerodynamic studies.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 2000
Accession Number
ADP010743

Entities

People

  • L. Robin

Tags

Communities of Interest

  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • Absorption Cross Sections
  • Air Flow
  • Boundary Layer
  • Chemical Reactions
  • Detection
  • Doppler Effect
  • Energy Transfer
  • Flow Visualization
  • Frequency
  • Gas Flow
  • Ground State
  • Laser Beams
  • Laser Induced Fluorescence
  • Measurement
  • Repetition Rate
  • Test Facilities
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Molecular Photonics/Laser Physics

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Hypersonics
  • Hypersonics - Hypersonic Flow