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Hypersonic flight vehicles have potential applications in strategic defence, space missions, and future civilian high-speed transportation systems. ...Scramjet-powered air-breathing hypersonic vehicles experience extreme heat loads induced by combustion, shock waves and viscous heat dissipation.

The urgent need to combat global warming has spurred legislative efforts within the transport sector to transition away from fossil fuels. Hydrogen is increasingly being utilised as a green energy vector, which can aid the decarbonisation of transport, including internal combustion engines. Computational fluid dynamics (CFD) is widely used as a tool to study and optimise combustion systems especially in combination with new fuels like hydrogen. Since the behaviour of the injection event significantly impacts combustion and emissions formation especially in direct injection applications, the accurate modelling of H2 injection is imperative for effective design of hydrogen combustion systems. This work aims to evaluate unsteady Reynolds-Averaged Navier Stokes (URANS) modelling of the advective transport process and related numerical methods.

Actual research activities are focused on the development of advanced HVOF sprayed coating systems on cylinder liners, the coating optimization and the cost effective implementation of this technology in an automated series production process. In hypersonic flame spraying (HVOF), the coating is deposited by an elliptically moving HVOF gun, whereas the cylinder liner is rotating.

The used thermal spray processes are high-energetic (Atmospheric Plasma Spraying) and high-energetic hypersonic deposition methods (High Velocity Oxygen Fuel Spraying). The knowledge of the mechanical and thermophysical properties of coatings is a key requirement for an optimized stable and repeatable manufacturing process as well as for reproducible high quality composites.

Plasma-sprayed coatings of Cr2O3 and hypersonic flame-sprayed coatings of cobalt-bonded WC performed particularly well as ring coatings.

The high Mach number supersonic bomber and its commercial transport version represent a challenge not only to designers but to fuel suppliers. Opinions differ on the relative importance of speed, structure and power plant but most designers are agreed that, compared to today's jet aircraft, the supersonic jet is far more fuel dependent in terms of both quality and cost. Fuel represents about 50% of gross take-off weight and accounts for over 50% of direct operating costs in the supersonic transport. The higher fuel consumption of supersonic jet engines means that the SST consumes more fuel to move the same traffic over a given route than the subsonic jet. As a consequence, a significantly greater demand for jet fuel will exist if some portion of world traffic moves supersonically rather than by conventional aircraft. Economic analysis indicates that fuel costs significantly greater than current fuel might wipe out the incentive for airlines to acquire a SST instead of a subsonic jet.