In order to find the combustion characteristic of PMMA in solid fuel ramjet combustor, the numerical simulation was carried out. The combustion flow was described with RNG k-ε turbulent model, Eddy Dissipation turbulent combustion model and first order upwind scheme, then the flow field structure, temperature and species distribution in solid fuel ramjet combustor were analyzed. By comparing the numerical calculation results and abroad test data, the reliabilities of the CFD were verified. The results show that as the axial distance increases, the local regression rate increases at first then decreases gradually. In addition, the increase of inlet air temperature and inlet air mass flow rate induces the increase of mean regression rate of PMMA approximately exponential increase and the combustor temperature. Compared with test data, the calculated value of fuel regression rate was slightly larger,caused possibly by the result that effective gasification heat was regarded as a constant and the two step irreversible reactions.%为了解PMMA在固体燃料冲压发动机燃烧室内的燃烧特性,采用RNG κ-ε模型、涡耗散湍流燃烧模型和一阶迎风格式,对以PMMA为燃料的固体燃料冲压发动机燃烧室进行了数值模拟,得到了燃烧室内的流场结构、温度及组分分布.通过比较数值计算结果与国外试验数据,验证了该数值方法的可靠性.研究表明,随着轴向位置的增大,燃料局部退移速率先增大后减小.增大入口空气温度和质量流率,均使平均退移速率近似指数关系增大,燃烧室温度随之增大.此外,与试验值相比,燃料退移速率计算值稍大,可能是有效气化热取常数及2步不可逆反应引起的结果.
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