Title: NUMERICAL SOLUTIONS OF THE FLOW FIELD PRODUCED BY A PLANE SHOCK WAVE EMERGING INTO A CROSSFLOW

The phenomena of a shock wave propagating into a supersonic crossflow is described mathematically using a finite difference technique. The transient shock discontinuity was modelled by an artificial dissipative schema in the difference technique. The results of three special cases for the shock-crossflow interaction are presented, and show that numerical schema using artificial dissipative techniques seem to provide a means of solving more complex interaction phenomena. (auth)

An investigation was made of the interaction of a magnetic field and the flow of ionized and electrically conductive argon. The following three configurations are considered: (1) a magnetic field transverse to the axis of either a rectangular or a circular shock tube; (2) an axially symmetric magnetic field as produced by a coil concentric with a circular shock tube; and (3) a radial magnetic field in an annular shock tube. The shock tube walls are assumed to be non-conductive. The axial components of the ponderomotive forces that act on the gas as a result of its motion through themore » magnetic field are calculated for each of the three cases. The analysis is based on the assumption of a weakly conductive gas. The results show that the distribution of the axial ponderomotive forces over the tube cross section is basically non-uniform for the cases (1) and (2), whereas the uniformity is reasonably good for an annular tube with typical geometry. The behavior of the flow of an ionized gas under the action of the axial ponderomotive force components was determined by considering the flow to be one-dimensionai. The results indicate that the use of ideal gas flow equations is inadequate to give a correct picture of the flow of a gas with equilibrium ionization. The limiting conditions beyond which a shock wave cannot be reflected off the magnetic field are considered and the results of calculations to determine the choking conditions in the flow of an ionized gas are presented. The results for the limiting conditions for the occurrence of a reflected shock wave, which were evaluated for a couple of typical cases, show that: (1) at a given experimental presboth for very low and very high shock Mach numbers; and (2) at a given shock Mach number the reflected shock wave is not expected to occur above a certain pressure level. Comparative calculations for neon indicate that for this gas at a given pressure level and shock Mach number, the reflected shoek wave will occur at tower magnetic field strengths than would be required to produce reflected shock waves in argon. (auth)« less

Shock wave flows of speeds to 1 cm/ mu sec were observed to interact with a magnetic field of 5700 gauss. A reflected shock is observed and the deceleration of the flow is measured. Gas flows to Mach 63 in krypton are produced by an annular electric shock tube powered by a discharge of long time constunt. A radial magnetic fleld provides closed paths within the gas flow for the induced currents. The speed of the wave reflected off the magnetic field is found to increase with interaction strength. The flow momentum lost per particle as the flow traverses themore » field region, is calculated and compared to the impulse delivered each particle by the magnetic field. Agreement is found over a wide range of experimental conditions, validating the magnetohydrodynamic picture of the interaction and the use of the scalar gas conductivity. (auth)« less