The entry-glide guidance strategy for hypersonic vehicles that can satisfy both terminal and path constraints is investigated in this paper.We propose a quasi-equilibrium glide adaptive guidance methodology based on t...The entry-glide guidance strategy for hypersonic vehicles that can satisfy both terminal and path constraints is investigated in this paper.We propose a quasi-equilibrium glide adaptive guidance methodology based on the quasi-equilibrium glide condition(QEGC),which innovatively utilizes the quasi-equilibrium glide phenomenon in lifting entry.With the aid of QEGC,both range and terminal velocity can be predicted analytically with high precision.The path constraints are converted into angle of attack constraints,which has been difficult to realize by using traditional predictive guidance methods.The algorithm is independent of the standard trajectory.All the guidance commands,including the bank angle and the angle of attack,are calculated analytically in real time,which endows the algorithm with sufficient adapbility.The results of a CAV-H vehicle guidance test show that the algorithm leads the vehicle along a quasi-equilibrium glide trajectory satisfying both the terminal and path constraints and has sufficient flexibility for occasional mission changes.Furthermore,the robustness of the guidance algorithm under disturbances is validated through a Monte Carlo simulation.展开更多
Q&P钢的连续退火工艺是一种广泛采用的热处理办法,本文从热力学的角度讨论了连续退火工艺均热过程数种Q&P钢奥氏体化的程度。重新计算了Fe-Si-Mn-C四元系固溶相BCC_A2和FCC_A1的热力学性质。结合连续退火工艺均热段的快速加热,...Q&P钢的连续退火工艺是一种广泛采用的热处理办法,本文从热力学的角度讨论了连续退火工艺均热过程数种Q&P钢奥氏体化的程度。重新计算了Fe-Si-Mn-C四元系固溶相BCC_A2和FCC_A1的热力学性质。结合连续退火工艺均热段的快速加热,短时保温,快速冷却的热处理工艺特点,按照PLE(Partition local equilibrium)和NPLE(Negligible partition local equilibrium)局部平衡计算了当前几种Q&P钢成分的FCC相线和奥氏体体积分数,并根据试验观测结果,提出了一种符合连续退火生产Q&P钢实际需求的准平衡相图计算方法:“准PLE”(Quasi-partition local equilibrium)计算方法,实际观测结果与理论预测结果符合较好。展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 61104200)
文摘The entry-glide guidance strategy for hypersonic vehicles that can satisfy both terminal and path constraints is investigated in this paper.We propose a quasi-equilibrium glide adaptive guidance methodology based on the quasi-equilibrium glide condition(QEGC),which innovatively utilizes the quasi-equilibrium glide phenomenon in lifting entry.With the aid of QEGC,both range and terminal velocity can be predicted analytically with high precision.The path constraints are converted into angle of attack constraints,which has been difficult to realize by using traditional predictive guidance methods.The algorithm is independent of the standard trajectory.All the guidance commands,including the bank angle and the angle of attack,are calculated analytically in real time,which endows the algorithm with sufficient adapbility.The results of a CAV-H vehicle guidance test show that the algorithm leads the vehicle along a quasi-equilibrium glide trajectory satisfying both the terminal and path constraints and has sufficient flexibility for occasional mission changes.Furthermore,the robustness of the guidance algorithm under disturbances is validated through a Monte Carlo simulation.
文摘Q&P钢的连续退火工艺是一种广泛采用的热处理办法,本文从热力学的角度讨论了连续退火工艺均热过程数种Q&P钢奥氏体化的程度。重新计算了Fe-Si-Mn-C四元系固溶相BCC_A2和FCC_A1的热力学性质。结合连续退火工艺均热段的快速加热,短时保温,快速冷却的热处理工艺特点,按照PLE(Partition local equilibrium)和NPLE(Negligible partition local equilibrium)局部平衡计算了当前几种Q&P钢成分的FCC相线和奥氏体体积分数,并根据试验观测结果,提出了一种符合连续退火生产Q&P钢实际需求的准平衡相图计算方法:“准PLE”(Quasi-partition local equilibrium)计算方法,实际观测结果与理论预测结果符合较好。
