DRIVER GAS CONTAMINATION IN SHOCK TUNNELS
Abstract
Shock tunnels are normally operated with flow times of many milliseconds, as indicated by an approximately constant reservoir pressure. This testing time is at a maximum under conditions of contact surface tailoring. It is shown how considerable amounts of driver gas can penetrate far into the test gas and contaminate the latter much sooner than the arrival of the bulk of the driver gas. Under certain conditions, this process can drastically shorten the constant properties testing time, without materially affecting the pressure. High speed gas sampling results confirm this phenomenon in a shock tunnel, and indicate the arrival of large concentrations of driver gas in less than half the time indicated by pressure records. A possible mechanism for premature arrival of driver gas, by bifurcation of the reflected shock, is described.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1968
- Accession Number
- AD0682129
Entities
People
- J. K. Richmond
- R. J. Parsons
Organizations
- Boeing