【摘要】 根据气、固两相局部非热平衡假设,建立了RSCP系统的二维非稳态数学模型,对于固体能量方程中的辐射源项采用辐射传递的有限体积法求解,研究了当量比、换向半周期、混合气流速对温度分布、辐射热流量和放热率的影响,考察了最高温升和可燃极限与这些参数之间的关联.研究表明,燃烧室内温度呈梯形分布,高温区较宽;气体的最高温度明显高于绝热火焰温度;贫可燃极限显著扩展,对提高燃烧效率和节约能源有重要作用.更多还原

【Abstract】 Taking into account non-local thermodynamic equilibrium between the porous media and premixed gases by introducing separate energy equations for the gas and solid phases, two-dimensional unsteady mathematical model for reciprocating superadiabatic combustion of premixed gases (RSCP) in porous media has been developed in the present study.The finite volume method is applied to solve the radiative source term in the energy equation of solid phase. The influences of the dominating working parameters, such as equivalence ratio, half cycle and flow velocity, on the temperature distributions, radiation flux and heat release rate are discussed. The relationship between the maximum temperature difference and the parameters are examined and the influence of the parameters on combustible limit is ascertained. The results show that the temperature profile inside the combustor has a typical trapezoidal shape and the domain of the central plateau temperature almost covers half of the combustor; the maximum gas temperature is remarkably higher than the theoretical flame temperature and the combustible range can be extended obviously. It reveals that the RSCP can make an impact role on energy saving and combustion efficiency improving.更多还原