双喷管运载火箭起飞阶段发射平台热环境研究

Investigations on thermal environment of launch pads during the two-nozzle launch vehicle launching

以双喷管运载火箭动力系统构成的发射平台为研究对象,采用数值模拟的方法对火箭起飞阶段发射平台的热环境展开研究。基于三维可压缩Navier-Stokes方程、k-ε方程湍流模型、2阶迎风TVD(total variation diminishing)离散格式,构建了双喷管运载火箭燃气射流模型。研究表明:喷管中心轴线与导流槽的交点处为导流面的冲击最大处,温度和压强极高,火箭尾焰射流冲击导流槽造成的反溅可能会进一步恶化发射台的热环境。火箭起飞过程中的漂移会加大射流对发射台的冲击,使其表面温度和压强迅速升高,减少其使用寿命。该研究为运载火箭起飞阶段发射平台的热环境评估提供了有效的方法,对热防护系统的安全设计具有重要的工程应用价值。

Taking the launch pads consisting of two-nozzle launch vehicle power system as the research object,the thermal environment of launch pads during the rocket launching was studied by numerical simulation method.Based on three-dimensional compressible Navier-Stokes equations,k-εturbulence model and second order TVD(total variation diminishing)upwind scheme were used to establish the gas jet model of two-nozzle launch vehicle.The research showed that the intersections of the nozzle central axis and the flame deflectors withstood the greatest impact of the guide surface,where the temperature and pressure were extremely high.The back splash caused by the rocket tail jet impinging on the flame deflectors may further deteriorate the thermal environment of the launch pad.The drift of the rocket during launching could increase the impact of the jet on the launch pad,rapidly increase its surface temperature and pressure,and reduce its service life.The research method provides an effective method for the thermal environment assessment of launch pads during launch vehicle takeoff and has important engineering application value for the safety design of thermal protection system.