To demonstrate agreement within 10% between simulated and measured performance along the operation sequence of the propulsion system, including warm-up / child-own, start-up, throttle-up and shutdown.

System modelling tools allow analysis of the propellant chemical and fluid dynamic behaviour through the complete propulsion system, from the tanks through the connecting pipes, valves, manifolds, combustion elements and nozzles. These tools support the design and verification of rocket propulsion systems and troubleshoot anomalies during the utilisation phase.The appearance of new propulsion concepts necessitates extensions of these numerical tools. More specifically, the start-up of rocket engines is a very demanding process that constraints the hardware and is addressed in the early design phases. The system modelling tools allow the assessment of the transient response of rocket and rocket based propulsion systems during the complete sequence, i.e. including chill-down / warm-up, start-up, throttle-up/-down and shut-down.The increasing interest in new propellant combinations (LOX/CH4, solid propellant and green propellants) require both new and enhanced physical models to capture the relevant phenomena within the combustion and catalyst components. Additionally, the development of a new rocket engine requires detailed time resolved simulation of the system. The transient simulations shall capture each relevant phenomenon, namely chemical, thermal, fluid dynamic, and allow optimum design and control and stochastic simulation within an affordable run time. The availability of high fidelity system modelling tools is essential to enable model-based engineering and hence support FMEA as well as prognostic health management of rocket engines. This is especially relevant nowadays, when the interest in reusability and new rocket configurations is increasing.The activity encompasses the following tasks :- Use of the complete spectrum of simulation tools, from high to low fidelity as necessary, to support the development and validation of novel or improved numerical methodologies. The developed models shall perform with an affordable runtime and be accurate for the assessment at system level of the following phenomena: instabilities in the catalysts of mono-propellant thrusters; heat and mass transfer in novel injectors for LOX/CH4; pyrolysis and coking phenomena; finite rate chemistry; turbo-machinery thermal, mechanical and fluid dynamic transient.- Validation of the developed system-modelling tool with measured transient-data of a mono-propellant and a bi-propellant propulsion system along the operational sequence, comprising warm-up / chill-down, start-up, throttle-up and shutdown.