Importance of turbulence for space launchers -: art. no. 056

This paper will show how turbulence plays a leading role in the design of space launching systems. It presents several areas for which turbulent flows represent critical issues either for the reliability of the systems or for their operational performance. Turbulence is a leading physical phenomenon involved in both the external aerodynamics of space vehicles as well as in the operation of their propulsive systems. Physical issues concern, for instance, unsteady low-velocity and large-scale atmospheric aerodynamics, subsonic, trans-sonic and supersonic vehicle aerodynamics, re-entry aerothermodynamics, single- and multiple-phase mixing and combustion, aerodynamics and hydraulics of turbomachinery. The mastering of these complex phenomena is a critical challenge for the space industry if it is to propose, in the future, reliable and high-performance systems with ambitious low-cost objectives.