Velocity and Density Determination by the Electron Beam Technique

In aerothermodynamic gas flows the accurate knowledge of the flow velocity and the density is important as the Mach number is in the hypersonic range and relatively insensitive against real gas effects. This is true especially in the case of rarefied flows if the deviation of the continuum flow condition takes place, viscous effects have to be taken into account, and mixtures of gases have to be considered.