可压缩算法在燃油冷却数值研究中的应用

Application of Compressible Algorithm in Numerical Simulation of Fuel-Active-Cooling

关键词:  燃油主动冷却  数值模拟  可压缩算法  预处理

Key words:  Fuel-active-cooling  Numerical simulation  Compressible algorithm  Precondition

摘要:

为深入研究超燃冲压发动机的燃油主动冷却过程，在可压缩算法框架下，引入预处理技术、低耗散数值离散格式、一般流体状态方程、高压物性模型、燃油裂解模型等，发展了一套适用于求解一般流体低速可压缩问题的数值模拟方法。利用电加热管试验对数值方法进行了验证，并定量研究了PR-3燃油的冷却需求量及平板面板冷却槽道布置的影响。结果表明，数值结果与试验符合很好，证明当前数值方法在燃油冷却数值模拟中是准确有效的。针对350mm×90mm×6mm的平板面板冷却过程，需要约10g/s的燃油可确保1WM/m2热流下的防热安全。槽道布置对温度场影响明显，两侧进油方式比单侧进油的最大温差低约150K，均温性更好，更有利于降低结构热应力。

Abstract:

In order to study the fuel-active-cooling of scramjet， a numerical simulation method suitable to solve the low-speed compressible problems of general fluid was developed. Based on the framework of compressible algorithm， the method introduced precondition technology， low dissipation numerical scheme， general fluid state equation， physical property model of high pressure and fuel pyrolysis model. The results of electrically heated tube test were adopted to verify the physical models and algorithms. The mass flow rate of RP-3 fuel for cooling process of flat panel was analyzed quantitatively and the effects of the cooling channel arrangement on cooling process were studied. The results show that the physical models and algorithms are effective on fuel cooling. The mass flow rate of RP-3 should be more than 10g/s to ensure the thermal protection safety under 1MW/m2 heat flux when the size of flat panel is 350mm×90mm×6mm. The channel arrangement has obvious influence on the temperature field. The maximum temperature difference when there are two oil inlets is 150K lower than that when there is only one oil inlet. Better isothermal performance means it is beneficial to the decrease of structure thermal stress.