In order to investigate the heat transfer of solid fuel surface and regression rate of solid fuel ramjet (SFRJ) effect by swirl flow

high-density polyethylene (HDPE) was used as fuel of SFRJ

the experiments were conducted by using connected pipe facility. And a two-dimensional axisymmetric turbu1ent f1ow and combustion program was developed

the heat transfer between fluid and solid domains was considered

and unsteady time method was used to simulate the case of experiment. The results indicated that the heat transfer in recirculation zone and reattachment point was higher than that in redevelopment zone

and the heat transfer of fuel surface had an appreciable effect on regression rate. Due to the function of centrifugal force and tangential velocity provided by swirl flow

this can lead to the long residence of pyrolysis of HDPE

and has positive effect on the combustion efficiency near the fuel surface. Moreover

the swirl flow can also increase the ability of heat transfer of fuel surface

the heat transfer coefficient was 100% higher than that of non-swirl flow. Compared with non-swirl flow

the combustion achieved for stability could be faster with swirl flow. The experimental result indicate that the introduction of swirl flow has a positive effect on improving the regression rate of SFRJ about 26%

but it can also lead to periodic oscillation of the pressure after burning chamber.