固冲发动机补燃室内强迫对流条件下硼颗粒燃烧速率研究

摘要

In the secondary combustion chamber of ducted rocket, there always exists a relative speed between the boron particle and air stream. Hence, it is required to study the effect of forced convection on the burning rate of the boron particle. The analysis made use of the boundary layer and flame-sheet approximations to describe the reacting flow. The governing boundary layer equations were solved by expanding the velocity, temperature and species distributions into series of azimuthal angle. Profiles of these variables at several angular positions along the particle surface were presented. An explicit expression for the burning rate of the boron particle was developed in terms of the Reynolds and mass transfer numbers. The partial differential equations for the two-dimensional boundary layer were simplified into a set of ordinary differential equations by a similarity transformation and then their numerical solution can be easily obtained.%硼颗粒在通过固体火箭冲压发动机的燃气发生器喷管进入补燃室的过程中,颗粒通常都会受到高速气流的作用.此时,静止条件下硼颗粒的燃烧模型不再适应.对强迫对流条件下的硼颗粒燃烧的二维问题建立了数学模型,通过物理、数学简化,将偏微分方程组化为易于求解的常微分方程组,最后得到燃烧速率的显示表达式,并进行了求解,给出了硼颗粒周围边界层内温度场、浓度场及颗粒燃烧速率随雷诺数Re的变化规律.