Abstract: Numerical simulation and direct connected test methods are used to study the influences of selected factors on the fuel surface regression rate of polymethylmethacrylate (PMMA) in a solid fuel ramjet. The influences of air mass flux and fuel internal diameter on the solid fuel average regression rate and local regression rate are studied. The results show that the temperature, heat flux and local regression rate of the solid fuel surface firstly increase and then decrease gradually along the axial direction, and reach the maximum values at the reattachment point in the end of the recirculation zone. The local regression rate of the fuel surface increases with the inner radius of fuel, but decreases with the mass flux of the air. The average regression rate of the fuel shows an increasing power function relation with air mass flux and a decreasing power function relation with fuel internal diameter. The numerical simulation results are coincident with the experimental results, and are slightly larger than experimental results. The maximum error is less than 10%.

Key words: ordnance science and technology, solid fuel ramjet, PMMA, regression rate