The velocity interferometer system for any reflector(VISAR) coupled with a streaked optical pyrometer(SOP) system is used as a diagnostic tool in inertial confinement fusion(ICF) experiments involving equations of sta...The velocity interferometer system for any reflector(VISAR) coupled with a streaked optical pyrometer(SOP) system is used as a diagnostic tool in inertial confinement fusion(ICF) experiments involving equations of state and shock timing.To validate the process of adiabatically compressing the fuel shell through precise tuning of shocks in experimental campaigns for the double-cone ignition(DCI) scheme of ICF, a compact line-imaging VISAR with an SOP system is designed and implemented at the Shenguang-II upgrade laser facility. The temporal and spatial resolutions of the system are better than 30 ps and 7 μm, respectively. An illumination lens is used to adjust the lighting spot size matching with the target size. A polarization beam splitter and λ/4 waveplate are used to increase the transmission efficiency of our system. The VISAR and SOP work at 660 and 450 nm, respectively, to differentiate the signals from the scattered lights of the drive lasers. The VISAR can measure the shock velocity. At the same time, the SOP system can give the shock timing and relative strength. This system has been used in different DCI campaigns, where the generation and propagation processes of multi-shock are carefully diagnosed.展开更多
针对从基于压缩超快成像(Compressed Ultrafast Photography,CUP)的任意反射面速度干涉仪(Velocity Interferometer System for Any Reflector,VISAR)中获得的压缩图像中重构出冲击波二维条纹图像的问题,提出一种基于卡尔曼滤波的双约...针对从基于压缩超快成像(Compressed Ultrafast Photography,CUP)的任意反射面速度干涉仪(Velocity Interferometer System for Any Reflector,VISAR)中获得的压缩图像中重构出冲击波二维条纹图像的问题,提出一种基于卡尔曼滤波的双约束图像重构算法。该算法首先基于条纹图像具有的稀疏性和平滑性,将问题转化为基于小波与全变分双先验约束的优化问题,然后,考虑到实际成像的噪声问题,采用加权卡尔曼滤波对图像已有信息进行预测和调整,最后将卡尔曼滤波引入二步迭代阈值算法的迭代过程中,进而求解该双约束优化问题,实现压缩图像的精确重构。在大噪声仿真实验中,该算法重构图像的峰值信噪比和结构相似度分别提高了4.8 dB和14.81%,显著提高了图像重构质量。在实际实验中,该算法重构出了清晰的冲击波条纹图像,且将冲击波速度最大相对误差降低了9.57%和平均相对误差降低了2.2%,验证了该算法的可行性。展开更多
采用任意反射面激光位移干涉测试技术(Displacement Interferometer System for Any Reflector,DISAR)分别获得了聚酯薄膜飞片、铝/聚酯薄膜飞片及铜/聚酯薄膜飞片在金属箔电爆驱动下的速度历程。结果表明,在充电电压为25.4 kV时,聚酯...采用任意反射面激光位移干涉测试技术(Displacement Interferometer System for Any Reflector,DISAR)分别获得了聚酯薄膜飞片、铝/聚酯薄膜飞片及铜/聚酯薄膜飞片在金属箔电爆驱动下的速度历程。结果表明,在充电电压为25.4 kV时,聚酯薄膜飞片在加速腔中的有效加速时间为1.6μs,最高速度约4.4 km·s-1;铝/聚酯薄膜飞片和铜/聚酯薄膜飞片在加速腔中的有效加速时间均大于3.0μs,最高速度均小于4.0 km·s-1。电爆驱动时,飞片材料对其运动特性有较大影响。金属/聚酯薄膜飞片相对于聚酯薄膜飞片更利于保持飞片的运行姿态,但飞行同样距离时其速度要低。展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA25030500 and XDA25010300)the CAS Youth Interdisciplinary Team(Grant No.JCTD-2022-05)+2 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciencesthe National Natural Science Foundation of China(Grant Nos.11873061 and 12073043)the National Key R&D Program of China(Grant Nos.2022YFA1603200 and 2022YFA1603204)。
文摘The velocity interferometer system for any reflector(VISAR) coupled with a streaked optical pyrometer(SOP) system is used as a diagnostic tool in inertial confinement fusion(ICF) experiments involving equations of state and shock timing.To validate the process of adiabatically compressing the fuel shell through precise tuning of shocks in experimental campaigns for the double-cone ignition(DCI) scheme of ICF, a compact line-imaging VISAR with an SOP system is designed and implemented at the Shenguang-II upgrade laser facility. The temporal and spatial resolutions of the system are better than 30 ps and 7 μm, respectively. An illumination lens is used to adjust the lighting spot size matching with the target size. A polarization beam splitter and λ/4 waveplate are used to increase the transmission efficiency of our system. The VISAR and SOP work at 660 and 450 nm, respectively, to differentiate the signals from the scattered lights of the drive lasers. The VISAR can measure the shock velocity. At the same time, the SOP system can give the shock timing and relative strength. This system has been used in different DCI campaigns, where the generation and propagation processes of multi-shock are carefully diagnosed.
文摘针对从基于压缩超快成像(Compressed Ultrafast Photography,CUP)的任意反射面速度干涉仪(Velocity Interferometer System for Any Reflector,VISAR)中获得的压缩图像中重构出冲击波二维条纹图像的问题,提出一种基于卡尔曼滤波的双约束图像重构算法。该算法首先基于条纹图像具有的稀疏性和平滑性,将问题转化为基于小波与全变分双先验约束的优化问题,然后,考虑到实际成像的噪声问题,采用加权卡尔曼滤波对图像已有信息进行预测和调整,最后将卡尔曼滤波引入二步迭代阈值算法的迭代过程中,进而求解该双约束优化问题,实现压缩图像的精确重构。在大噪声仿真实验中,该算法重构图像的峰值信噪比和结构相似度分别提高了4.8 dB和14.81%,显著提高了图像重构质量。在实际实验中,该算法重构出了清晰的冲击波条纹图像,且将冲击波速度最大相对误差降低了9.57%和平均相对误差降低了2.2%,验证了该算法的可行性。
文摘采用任意反射面激光位移干涉测试技术(Displacement Interferometer System for Any Reflector,DISAR)分别获得了聚酯薄膜飞片、铝/聚酯薄膜飞片及铜/聚酯薄膜飞片在金属箔电爆驱动下的速度历程。结果表明,在充电电压为25.4 kV时,聚酯薄膜飞片在加速腔中的有效加速时间为1.6μs,最高速度约4.4 km·s-1;铝/聚酯薄膜飞片和铜/聚酯薄膜飞片在加速腔中的有效加速时间均大于3.0μs,最高速度均小于4.0 km·s-1。电爆驱动时,飞片材料对其运动特性有较大影响。金属/聚酯薄膜飞片相对于聚酯薄膜飞片更利于保持飞片的运行姿态,但飞行同样距离时其速度要低。
