外侧面燃烧固体燃料冲压发动机燃烧室流场的数值研究

Numerical Simulation on Flow Field of Solid Fuel Ramjet Combustion Chamber with Outboard Burning

关键词:  固体燃料冲压发动机  外侧面燃烧  燃面退移速率

Key words:  Solid fuel ramjet  Outboard burning  Regression rate

摘要:

为研究外侧面燃烧固体燃料冲压发动机燃烧室流场及燃面退移速率的特点，在Fluent平台上完成了内孔、外侧面燃烧SFRJ的燃烧室内燃烧流场的数值计算。在所涉及的工况中，计算结果表明:外侧面燃烧的SFRJ中，再附着点之前，燃面退移速率较大，来流空气质量流率150g/s，总温600 K时，最大燃面退移速率比内孔燃烧增大43.5%；再附着点之后，燃面退移速率快速减小；随着来流空气总温的减小，固体燃料末端的燃面退移速率开始沿轴向增大；随着来流空气质量流率的增大，燃面退移速率开始增大的位置不断前移，而其增大速率不断减小；因大部分区域内燃面退移速率较小，导致其平均燃面退移速率比内孔燃烧减小21.9%至40.5%；外侧面燃烧的推力比内孔燃烧的小，但比冲相差不大；补燃室及喷管表面处流场温度比内孔燃烧低500~1000 K。

Abstract:

To study the flow field and regression rates of solid fuel ramjet combustion chamber with outboard burning，the flow field of solid fuel ramjet combustion chamber with inner hole and outboard burning were calculated using Fluent software. Results show that for solid fuel ramjet with outboard burning，the value of regression rates on the upper stream of reattachment point is larger，the maximum value of regression rate is 43.5% more than inner hole burning，when the mass flux and total temperature of air are 150g/s and 600K，respectively. Regression rates on the downstream of reattachment point decrease rapidly. With reducing the total air temperature，the regression rates in the fully developed zone increase along the axis. The point that the regression rates start to increase is moved forward，and the increasing rate decrease when the mass flux of air increases. The mean regression rates are smaller 21.9% to 40.5% than inner hole burning as a result of small regression rates in most region. The thrust of outboard burning is lower than that of inner hole burning，but the specific impulse are similar. Temperature of flow field on the surface of aft-mixing combustion chamber and nozzle are 500～1000K less than inner hole burning.