To study the impact of radial cooling channel section characteristic length change on air cooled flameholder cooled flow field

the cooling performance and flow loss

and also provide reference for further optimization design

a numerical simulation was performed by using an experimentally validated CFD method. Within the range of the characteristic length

the results indicated that

increasing the characteristic length reduced the lower portion intake resistance of radial cooling channel

so the air pocket entraining rate caused an increase of 667%. Due to the impact of vortex

the mass flow of the vent holes at the lower portion was significantly lower than that at the upper portion. Changing characteristic length had little effect on the mass flow distribution. Increasing the characteristic length enhanced the outer wall cooling effect of radial flameholder adjacent to the ring flameholder

but weakened the outer wall cooling effect of radial flameholder close to the inner cone. Due to the increase of the characteristic length

outlet total pressure recovery coefficient decreased by 0086% and total pressure recovery coefficient distribution curve along the afterburner moved downward.