The unsteady, compressible Navier-Stokes equations in mass averaged variables are solved for flow past a bulbous shroud. For the freestream Mach number 0.8 and Reynolds number 3.37xl0/m, a time-dependent computation is performed, using MacC or mack's explicit finite-difference scheme with 64 X 30 grid points. The entire flowfield along the shroud is analyzed to capture a terminal shock and the separation zones. A comparison with available experimental results is reported and evaluation of the unsteady data for surface pressure fluctuations is presented.

A Navier-Stokes Solution for a Bulbous Payload Shroud

An analytical approach for stand-off distance of detached shock waves

Flowfield over bulbous heat shield in transonic and low supersonic speeds

Conclusions A numerical experiment of axisymmetric turbulent viscous flow over a bulbous heat shield is performed by employing a three-stage Runge-Kutta time-stepping scheme. Turbulence closure is achieved using the Baldwin-Lomax turbulence model. The flowfield visualization of the terminal shock and the separated region helps in a systematic understanding of flow structure under various freestream Mach numbers. The following observations are made based on the described numerical simulations. 1) The terminal shock moves downstream with increasing freestream Mach number. The strength of the terminal shock initially increases with Mach number and later decreases. The location of the terminal shock is found as a nonlinear function of the freestream Mach number. 2) The separation zone in the boat-tail region is found as a function of the freestream Mach number. The flowfield features of the separated region are found to be different in the transonic and supersonic Mach number ranges.

Euler solution of axisymmetric jets in supersonic external flow

Flowfield study over a bulbous payload shroud in transonic and low supersonic Mach number

The flow past a blunt cone-cylinder at transonic speeds and at moderate angles of incidence has been studied experimentally by recording (1) the longitudinal and circumferential pressure distribution, (2) the surface oil flow patterns using a suspension of titanium dioxide in oleic acid. The results indicate some interesting three-dimensional flow separation phenomenon at transonic speeds.

G Rajendra

Papers

Experimental investigation of transonic flow past a blunt cone-cylinder