Aerothermal Analysis of Reusable Launcher Systems during Retro-Propulsion Reentry and Landing

Abstract

The structural and thermal loads during first stage reentry may impact significantly the structural and thermal design and thus influence the payload perfor- mance and launch service cost of expendable launch vehicles. Many studies have focused on the effect of counterflowing jets emanating from blunt capsules on drag and aerothermal fluxes. However, for slender rocket shape bodies the database is still sparse. For this purpose CFD studies of the flow fields around a reusable first stage during reentry at freestream Mach numbers between 9.45 and 5.09 were carried out in close conjunction with the system analysis and trajec- tory design of potential future European carrier sys- tems. The results of this study show that the inte- gral heat uptake with hot retro-propulsion is gener- ally higher than heat uptake at a ballistic state. How- ever, the supersonic retro-propulsion maneuver redis- tributes the high heat loads from the baseplate area to the entire vehicle surface, therefore reducing local thermal loads.