By reproducing the first 60 seconds of the ascent flight of the Shefex II rocket on the computer, researchers from the DLR Institute of Aerodynamics and Flow Technology provided for the first time an example of a numerical flight experiment from space transport.
The SHEFEX-II module called "Sharp Edge Flight Experiment", which measured 12.6 meters with rocket, was launched from the Norwegian rocket base Andøya in 2012. The researchers recalculated this hypersonic flight on the high-performance computer CASE in Braunschweig. 192 processor cores were used on the cluster for three months to simulate real flight with a highly accurate simulation environment. The researchers coupled the simulation methods DLR TAU (URANS), the orbit program REENT (atmosphere under consideration of the wind on launch day, with complete gravitational model of the rotating, elliptical Earth), ANSYS (FEM for the deformation of the fins) and the jet flow (the original exhaust gas jet of the solid fuel engine). A comparison of the simulation and measurement data revealed: Within the scope of expected error deviations on both sides and under the influence of all effects that occurred, numerical and real flight were in very close agreement. Individual investigations of different influences provided detailed insights into the flight experiment. The generated coupling environment can be used in further research and projects to develop future high-performance spacecraft in terms of flight altitude, flight speed, flight duration and maximum payload.
As seen in the video, the Shefex II rocket nods out of the launch pad after two seconds during launch and spins itself up for roll stabilization. The slightly transparent section through the field shows here the Mach number, which is a multiple of the local sound velocity. The pressure distribution is colored on the surface. The trajectory and the body's own axes are also displayed to illustrate the "spinning" movement.