随着光学遥感小卫星高分辨率、高集成度、高敏捷等需求提升,部分卫星同时配置可见红外一体化相机与控制力矩陀螺(control moment gyroscope,CMG),兼顾轻小型化与全天时、多目标、多模式成像要求。针对此类卫星存在CMG、红外相机制冷机...随着光学遥感小卫星高分辨率、高集成度、高敏捷等需求提升,部分卫星同时配置可见红外一体化相机与控制力矩陀螺(control moment gyroscope,CMG),兼顾轻小型化与全天时、多目标、多模式成像要求。针对此类卫星存在CMG、红外相机制冷机等多个扰振源,且对于相机成像质量影响大、抑制难等挑战,对基于上述扰振源的微振动综合抑制方法进行了研究,包括设计、安装CMG隔振器、将红外相机制冷机压缩机与相机光机主体隔振安装,设计、安装阻尼桁架实现相机主体与卫星平台舱结构之间的隔振等。通过综合应用上述扰源减振、终端隔离等措施,经分析计算与整星微振动及在轨实际测试与验证,能够有效降低微振动对图像质量的影响,即使对于可见红外一体化相机,分辨率为亚米级的可见光通道在轨动态调制传递函数(modulation transfer function,MTF)也能够达到0.1,微振动对可见相机MTF的影响因子可控制到0.991。展开更多
Early water breakthrough and a rapid increase in water cut are always observed in high- permeability completion intervals when perforations are uniformly distributed in the wellbore in heterogeneous reservoirs. Optimi...Early water breakthrough and a rapid increase in water cut are always observed in high- permeability completion intervals when perforations are uniformly distributed in the wellbore in heterogeneous reservoirs. Optimization of perforating parameters in partitioned sections in horizontal intervals helps homogenize the inflow from the reservoir and thus is critically important for enhanced oil recovery. This paper derives a coupled reservoir-wellbore flow model based on inflow controlling theory. Genetic algorithms are applied to solving the model as they excel in obtaining the global optimum of discrete functions. The optimized perforating strategy applies a low perforation density in high- permeability intervals and a high perforation density in low-permeability intervals. As a result, the inflow profile is homogenized and idealized.展开更多
文摘随着光学遥感小卫星高分辨率、高集成度、高敏捷等需求提升,部分卫星同时配置可见红外一体化相机与控制力矩陀螺(control moment gyroscope,CMG),兼顾轻小型化与全天时、多目标、多模式成像要求。针对此类卫星存在CMG、红外相机制冷机等多个扰振源,且对于相机成像质量影响大、抑制难等挑战,对基于上述扰振源的微振动综合抑制方法进行了研究,包括设计、安装CMG隔振器、将红外相机制冷机压缩机与相机光机主体隔振安装,设计、安装阻尼桁架实现相机主体与卫星平台舱结构之间的隔振等。通过综合应用上述扰源减振、终端隔离等措施,经分析计算与整星微振动及在轨实际测试与验证,能够有效降低微振动对图像质量的影响,即使对于可见红外一体化相机,分辨率为亚米级的可见光通道在轨动态调制传递函数(modulation transfer function,MTF)也能够达到0.1,微振动对可见相机MTF的影响因子可控制到0.991。
基金supported by National Scientific Project(No. 2008ZX05024-03)
文摘Early water breakthrough and a rapid increase in water cut are always observed in high- permeability completion intervals when perforations are uniformly distributed in the wellbore in heterogeneous reservoirs. Optimization of perforating parameters in partitioned sections in horizontal intervals helps homogenize the inflow from the reservoir and thus is critically important for enhanced oil recovery. This paper derives a coupled reservoir-wellbore flow model based on inflow controlling theory. Genetic algorithms are applied to solving the model as they excel in obtaining the global optimum of discrete functions. The optimized perforating strategy applies a low perforation density in high- permeability intervals and a high perforation density in low-permeability intervals. As a result, the inflow profile is homogenized and idealized.
