双燃烧室冲压发动机富油燃气超声速燃烧数值模拟

Numerical Simulation on Supersonic Combustion of Fuel-rich Gas for a Dual Combustor Ramjet

文中对双燃烧室冲压发动机主燃室中富油燃气超声速燃烧进行了数值模拟。在模拟飞行马赫数6情况下,研究了亚燃室出口燃气马赫数、压力及燃气与超燃进气道出口热空气的压力匹配程度等多种因素对流场的影响。结果表明,保持热空气马赫数不变,燃气马赫数越低,混合层增长越快;燃烧促进了混合层增长,燃气马赫数较高时,燃烧对混合层增长的促进作用受到抑制;来流压力不匹配程度越大,流场波系越强,混合层和激波相互作用后偏折越厉害;燃气/空气压力比小于1时,混合层和燃烧释热区均有所增大。

A numerical simulation is conducted for supersonic combustion of fuel-rich gas in DCR＇s main combustor in this paper. Many factors including the Math number and pressure of the gas from subsonic eombustor, the pressure matching relations between the heated air from scramjet inlet and the gas are explored at the flight condition of Mach number 6 to investigate their important influences on the flow field. The results show that at a fixed Maeh number of heated air, the lower roach number of the gas, the better mixing of the air and gas. The combustion promotes the growth of mixing layer, but the promoting effect is restrained at a higher Math number of gas. The bigger the nonmatching extent of pressure results in the stronger flow wa.ves, and the heavier deflection of mixing layer after affected by shock wave. When the ratio of the pressure is less than 1, the region of mixing layer and heat release is bigger.