Pylon Fuel Injector Design for a Scramjet Combustor

Abstract

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Computational Simulation of Scramjet Combustors - A Comparison between Quasi-One Dimensional and 2-D Numerical Simulations

“…The parallel injection schemes have lower combustion efficiency due to poor mixing at supersonic speeds, but as per Dimotakis [61], the mixing efficiency can be enhanced using parallel injection scheme if it were accompanied with generation of axial vorticity [55]. These axial streamwise vortices produce turbulent fluctuations perpendicular to the flow, thus breaking down large 2-D flow structures into small turbulent vortices which enhance diffusion and mixing [62]. Wall injection techniques comprising of wedge-shaped geometrical structures, such as ramps or Hypermixers, can be used for inducing axial vorticity into the flowfield.…”

“…Low angled wall injection or ramp injection techniques require high fuel injection pressure for gaining deep fuel penetration within the core of the crossflow [62]. Instead the struts can be used for injecting fuel directly into the core of mainstream with lower injection pressures [62].…”

“…A strut spans across the entire width or height of the combustor and attaches to both the combustor walls [62]. Apart from injecting fuel into the core of the mainflow, a strut injector promotes uniform spreading of the fuel in the lateral direction [67].…”

“…Instead the struts can be used for injecting fuel directly into the core of mainstream with lower injection pressures [62].…”

“…Pylon injectors like strut injectors are used for injecting the fuel within the core of the mainflow with lower injection pressures [62]. Injecting the fuel within the core of mainflow, aids to utilize the fuel momentum for gaining higher thrust output from the propulsion system.…”