A design method based on tip to tail streamline tracing and osculating inward cone methods is discussed for designing the integrated Osculating Inward Cone Waverider Inlet（OICWI）. A practical geometrical constrained...A design method based on tip to tail streamline tracing and osculating inward cone methods is discussed for designing the integrated Osculating Inward Cone Waverider Inlet（OICWI）. A practical geometrical constrained experimental model of OICWI is designed based on the validated design method. It has a total contraction ratio of 4.61 and inner contraction ratio is 2.0. Wind-tunnel tests have been conducted for the OICWI model at free stream Mach number（Ma） of 4.0, 3.5 and 3.0 respectively. The experimental results show that the OICWI has high flow capture ratio and compression abilities. It can self-start at Ma= 3.5 and 4.0 and its flow capture ratio is 0.73 at Ma= 4.0, and Angle of Attack（AOA） 0°. The research results show that the OICWI has advantages of inward cone waverider and streamline tracing inlet. Present OICWI is a novel approach for waverider inlet integration studies and it will promote the use of waverider inlet integration configuration in the studies of airbreathing hypersonic vehicles.展开更多
The scramjet,which is the propulsion of hypersonic vehicle,has become the focus in many military developed countries.The ground tests play an important role in the research of scramjet.There is defect of test medium c...The scramjet,which is the propulsion of hypersonic vehicle,has become the focus in many military developed countries.The ground tests play an important role in the research of scramjet.There is defect of test medium contamination(the thermochemical characteristic of the ground test medium is different from that of the flight medium)in existing ground test facilities for scramjet combustor experiment.To solve the problem of test medium contamination,the first clean air heated facility of China for scramjet combustor experiment is designed.The key technology of designing the clean air heated facility is summarized.By using bypass duct,combustor model is protected from high temperature.To reduce the switching time between main duct and bypass duct,solenoid valve and water-cooled system were used.Having centrosymmetric structure,the heat radiating area of the facility and heat loss of the facility are much lower than others.Clean air heated facility is adopted to conduct experiment,which is the first experiment of China in clean air inflow,research on hydrogen-fueled and ethylene-fueled ignition and combustion for scramjet combustor at different equivalence ratio.Successful ignition and sustained combustion of hydrogen has been achieved.Successful ethylene ignition and sustained main stream combustion is achieved with normal fuel injection and taking hydrogen as pilot flame.Experiment result shows that the wall pressure of combustor model rises when the equivalence ratio of hydrogen rises.As the wall pressure of combustor model rises,the pressure disturbance influences the shock train in the upstream.展开更多
高精度气动优化是改善高超声速飞行器气动性能的必要途径。基于Navier-Stokes方程推导了连续伴随方程以及与气动力目标函数对应的边界条件和壁面灵敏度公式,考虑了层流输运系数变分对伴随方程的贡献,采用基于二阶熵修正Roe格式的伴随对...高精度气动优化是改善高超声速飞行器气动性能的必要途径。基于Navier-Stokes方程推导了连续伴随方程以及与气动力目标函数对应的边界条件和壁面灵敏度公式,考虑了层流输运系数变分对伴随方程的贡献,采用基于二阶熵修正Roe格式的伴随对流项离散形式,构造了适用于高超声速流动的连续伴随求解器;结合FFD(Free Form Deformation)参数化方法和SQP(Sequential Quadratic Programming)优化算法构建了高精度梯度优化框架;在高超声速来流条件下对二维翼型和Sanger飞行器机翼优化开展了验证和应用。结果显示,在高超声速流动条件下所采用的伴随对流项离散形式具有较好的鲁棒性和低耗散性;连续伴随求解器能够较好地给出气动力目标函数梯度;优化后Sanger机翼构型通过二次激波压缩实现了减阻增升,升阻比提高5.0%;验证了连续伴随优化作为高超声速飞行器高精度气动优化方法的可行性。展开更多
基金supported by the National Natural Science Foundation of China (Nos. 51376192 and 91216303)
文摘A design method based on tip to tail streamline tracing and osculating inward cone methods is discussed for designing the integrated Osculating Inward Cone Waverider Inlet（OICWI）. A practical geometrical constrained experimental model of OICWI is designed based on the validated design method. It has a total contraction ratio of 4.61 and inner contraction ratio is 2.0. Wind-tunnel tests have been conducted for the OICWI model at free stream Mach number（Ma） of 4.0, 3.5 and 3.0 respectively. The experimental results show that the OICWI has high flow capture ratio and compression abilities. It can self-start at Ma= 3.5 and 4.0 and its flow capture ratio is 0.73 at Ma= 4.0, and Angle of Attack（AOA） 0°. The research results show that the OICWI has advantages of inward cone waverider and streamline tracing inlet. Present OICWI is a novel approach for waverider inlet integration studies and it will promote the use of waverider inlet integration configuration in the studies of airbreathing hypersonic vehicles.
基金supported by National Hi-tech Research and Development Program of China(863 Program,Grant No.2003AA723072)
文摘The scramjet,which is the propulsion of hypersonic vehicle,has become the focus in many military developed countries.The ground tests play an important role in the research of scramjet.There is defect of test medium contamination(the thermochemical characteristic of the ground test medium is different from that of the flight medium)in existing ground test facilities for scramjet combustor experiment.To solve the problem of test medium contamination,the first clean air heated facility of China for scramjet combustor experiment is designed.The key technology of designing the clean air heated facility is summarized.By using bypass duct,combustor model is protected from high temperature.To reduce the switching time between main duct and bypass duct,solenoid valve and water-cooled system were used.Having centrosymmetric structure,the heat radiating area of the facility and heat loss of the facility are much lower than others.Clean air heated facility is adopted to conduct experiment,which is the first experiment of China in clean air inflow,research on hydrogen-fueled and ethylene-fueled ignition and combustion for scramjet combustor at different equivalence ratio.Successful ignition and sustained combustion of hydrogen has been achieved.Successful ethylene ignition and sustained main stream combustion is achieved with normal fuel injection and taking hydrogen as pilot flame.Experiment result shows that the wall pressure of combustor model rises when the equivalence ratio of hydrogen rises.As the wall pressure of combustor model rises,the pressure disturbance influences the shock train in the upstream.
文摘高精度气动优化是改善高超声速飞行器气动性能的必要途径。基于Navier-Stokes方程推导了连续伴随方程以及与气动力目标函数对应的边界条件和壁面灵敏度公式,考虑了层流输运系数变分对伴随方程的贡献,采用基于二阶熵修正Roe格式的伴随对流项离散形式,构造了适用于高超声速流动的连续伴随求解器;结合FFD(Free Form Deformation)参数化方法和SQP(Sequential Quadratic Programming)优化算法构建了高精度梯度优化框架;在高超声速来流条件下对二维翼型和Sanger飞行器机翼优化开展了验证和应用。结果显示,在高超声速流动条件下所采用的伴随对流项离散形式具有较好的鲁棒性和低耗散性;连续伴随求解器能够较好地给出气动力目标函数梯度;优化后Sanger机翼构型通过二次激波压缩实现了减阻增升,升阻比提高5.0%;验证了连续伴随优化作为高超声速飞行器高精度气动优化方法的可行性。
