Computational analysis of novel cavity-based flameholder designs for supersonic combustion engines

Abstract

Computational analysis for novel cavity-based flameholder designs with different fore-wall and aft-wall inclinations has been presented. The flameholder performance has been evaluated based on the following key parameters: pressure distribution, temperature distribution, recirculation zones and drag force. On comparing the different cavity designs, it has been found that both the fore-wall and aft-wall angles affect the flameholder performance. It was observed that an obtuse fore-wall angle gave favourable results numerically. Further studies can analyze cavities with different obtuse fore-wall ramp angles for optimum flameholder performance.

Effect of a Pylon Mounted Cavity-Based Flameholder on ‎the Combustor Flow Characteristics

“…Steady-State Two-dimensional Computations have been performed at a supersonic freestream Mach number of 3.0 over a fore-wall inclined (110°) cavity flameholder with a pylon mounted in the upstream of the cavity. The flow field developed over the cavity is captured and compared with that obtained over a cavity (fore-wall inclined by 110°) without a pylon as reported by the authors' previous work (Nayal et al 2020). The effect of mounting a pylon at the upstream of the fore-wall inclined cavity is investigated using qualitative as well as quantitative analysis.…”

“…The effect of mounting a pylon at the upstream of the fore-wall inclined cavity is investigated using qualitative as well as quantitative analysis. In order to analyze the effect qualitatively, the contour of normalized pressure, normalized temperature (ratio of static temperature to freestream temperature) and eddy formations captured from the present computations over a pylon based cavity are compared with those obtained over a cavity without a pylon as reported in Nayal et al (2020). Further, the pressure distribution, temperature distribution, turbulence kinetic energy distribution and drag coefficients generated over these models are also obtained and compared to quantitatively analyze the effect of mounting a pylon on the upstream of the The results obtained from the present computations and their comparisons with the reported results (Nayal et al 2020) are discussed in the following sub-sections.…”

“…An explicit density-based solver, with Green-Gauss cell-based scheme for spatial discretization, and Roe-FDS scheme for the inviscid fluxes has been adopted for the present computations. Turbulence model is set to k-ω, similar to the one adopted in the authors' previous work (Nayal et al 2020).…”

“…Figure 7 shows the normalized temperature contour for the cavity-only configuration as reported in Nayal et al (2020). In the case of cavity-only configuration, the shear layer is completely visible and the temperature is found to increase towards the negative Y axis (downward) from the freestream flow.…”

“…Other studies related to cavities have also been reported in open literature. In the authors' previous work (Nayal et al 2020), they introduced novel cavity designs by modification of the fore-wall ramp angles. The novel designs were computationally tested and it was identified that a cavity with a fore-wall inclination angle of 110 degrees was an ideal flameholder design amongst other cavities that were tested.…”