Rocket Engine Design and Analysis
An overview of rocket engine design, engineering and tools used by the EADS Astrium Ottobrunn team.
The expertise of Ottobrunn's rocket propulsion team is applied to the engineering, design, analysis and performance prediction of liquid propellant rocket engines and combustion chambers. This experience has been gathered over a period exceeding 40 years and has supported the well proven and successful design of rocket engines, rocket thrust chambers and associated systems covering a range of different propellants including monopropellants, earth storable hypergolic propellants, cryogenic propellants and more recently, alternative 'green' and hydrocarbon propellants.
Typical activities of the propulsion team include:
- Design and optimisation of rocket engine combustion chamber profile and nozzle cooling. Nozzle flow and performance analysis. Hydraulic characterisation of cooling channels (flow checks). Combustion chamber simulation and associated heat transfer analysis. Production monitoring and assessment of design deviations. Upgrade development and evolution of analytical and prediction models, software and tools. Characterisation of thrust chamber operating behaviour. Development of multiphase flow codes within national and international technology programmes under ESA/ESTEC contracts and R & D projects.
- Rocket engine test analysis of injection head and ignition, combustion chamber efficiency and cooling. Design of injection component set-up and configuration. Hydraulic flow check characterisation of elements. Hydraulic design of dome, distribution and manifolds. Design of ignition systems. Evaluation and assessment of flow checks for injection elements and cooling channels. Characterisation of thrust chamber operating behaviour. Definition of test requirements. Rocket engine flight test analysis and evaluation.
- Service life analyses. Improvement of service life model (database). Characterisation and analysis of crack propagation. Thrust chamber operating characterisation (Operating envelope programme).
A number of tools have been developed and are constantly being refined to support the design, analysis, modeling and performance prediction of rocket engines. These include tools for rocket engine combustion flow analysis, computation of thrust chamber flow phenomena, determination of heat transfer processes in rocket engine thrust chambers, characterisation of thrust chamber operational behaviour and the determination of heat transfer processes in rocket engine thrust chambers. The experienced use of these tools have repeatedly verified the accuracy of their predictions from the actual test and service life of rocket engines.
ROCFLAM: ROcket Combustion FLow Analysis Module. A Multiphase Navier-Stokes code for the computation of flow phenomena in thrust chambers using storable propellant combinations such as hydrazine/N2O4 and MMH/N2O4. Developed under ESA/ESTEC Contract for the simulation of film-cooled engines.
CryoROC: Cryogenic ROcket Combustion. A multiphase Navier-Stokes code for the computation of flow phenomena in thrust chambers using cryogenic oxygen and hydrogen. A derivative of the ROCFLAM code, linked with RFCS, the procedure allows the exact determination of heat transfer in regeneratively cooled thrust chambers. The code also enables an assessment of the impact of transpiration cooling and combustion chamber cracks on the performance of rocket engines and the prediction of solid particle acceleration in kinetically compacted cold gas injection nozzles as used for the Vulcain 2 and Vinci rocket engines.
RCFS: Regenerative Coolant Flow Simulation. A programme for the determination of heat transfer processes in rocket engine thrust chambers based on advanced Nusselt correlation's. Used for hypergolic and cryogenic propellant combinations, the programme is a partial module of CryoROC - for computation of heat transfer of the cooling agent, and partial module of Envelope - for the determination of heating-up. Used during the development of the Vulcain 2 and Vinci rocket engines.
A tool for the service life estimation of rocket combustion chambers, considering low cycle fatigue and creeping damage; used for RS-72, Vulcain 2 and Vinci developments.
A programme for the complete evaluation of rocket engine tests.