Fundamental and Experimental Aerodynamics

Viscous Interactions and Separation in Hypersonic Flow

A beam of electrons passing through a cylinder-skirt model
in order to measure a density profile in the model's
external boundary layer

The experiments carried out on a cylinder-skirt model in the R5Ch low Reynolds number wind tunnel allowed us to create an unequalled completely laminar test case that has been widely by the international community for validating the codes solving the Navier-Stokes equations, or those using the DSMC (Direct Simulation by Monte-Carlo) approach. Thus, at Onera's initiative, three Navier-Stokes codes (two from Onera and one from the University of Rome - La Sapienza) and a DSMC code (Nasa Langley) were evaluated.

This test case has been much enriched by density measurements obtained using a method based on the X radiation of nitrogen molecules excited by a beam of electrons, or Electron Beam Fluorescence (see the figures below). These measurements were taken in the framework of a collaborative project involving Onera (Physics, Instrumentation and Sensing Department - DMPH), the CNRS (Aerothermal Laboratory), and the Novosibirsk Institute of Thermophysics.

Successive density profiles measured by Electron Beam Fluorescence
in a laminar hypersonic interaction.
Tests at Mach 10 in the R5Ch wind tunnel

Last Update: 5 June 2006 - © ONERA 2009 - Terms of use