爆轰波在弯管内传播过程数值分析

应用基元反应模型和频散可控耗散格式(DCD)对氢氧爆轰波在弯管内的传播过程进行了数值模拟.计算中氢氧混合物化学反应采用了8种组分20个反应方程式.在处理化学反应引起的刚性问题时采用了时间算子分裂的方法.计算结果表明,在弯管小曲率半径壁面附近,由于膨胀稀疏作用,爆轰波强度减弱,在局部出现前导激波与放热反应区的解藕以及二次起爆现象;在弯管大曲率半径壁面上爆轰波在马赫反射和正规反射之间相互转变,使爆轰波加强.弯管内的爆轰现象与弯管曲率半径有关.

Scheme Construction with Numerical Flux Residual Correction (NFRC) and Group Velocity Control (GVC)

For simulating multi-scale complex flow fields like turbulent flows, the high order accurate schemes are preferred. In this paper, a scheme construction with numerical flux residual correction (NFRC) is presented. Any order accurate difference approximation can be obtained with the NFRC. To improve the resolution of the shock, the constructed schemes are modified with group velocity control (GVC) and weighted group velocity control (WGVC). The method of scheme construction is simple, and it is used to solve practical problems.

自适应光学对大气扰动波前的补偿效果研究：I.理论推导

在采用冻结湍流假设和几何光学近似的条件下，得到了经自适应光学系统校正后的剩余波前相位扰动的结构函数，进而根据剩余相位结构函数与系统Ｓｔｒｅｈｌ比的关系，求出自适应光学系统的补偿效果受系统的时空传递函数，大气湍流，光波传播路径上的横向风，观察目标的旋转角速度以及系统时间延迟影响情况的解析表达式。

含热传导的冲击动力学有限元程序的研究与应用

从有限变形的基本框架出发，建立了含热传导的冲击动力学基本控制方程和合适的初边条件。应用变分原理和伽辽金方法得出了控制方程相应的有限元列式，并探讨了数值计算中的几个关键算法，主要包括构型转换、旋转张量的算法、本构算法以及计算流程和程序框图等。利用自行研制的程序，对长脉冲激光辐照下靶目标的变形和破坏、冲击压缩变形及变形局部化等问题进行了数值模拟和研究，所得结果与实验和理论分析相吻合。

固井工程中的流动问题

同井是油气在建过程中的重要工程，一般分下套管和注水泥两个过程．本文结合作者近年来的研究，着重阐述了钻井液、前置液、水泥浆在环形空间中流动的流体力学问题，包括：高温高压下的水泥浆流变性、偏心环形空间中浆液的流动特性、钻井液-前置液和前置液-水泥浆界面的稳定性等，介绍了国内外学者对这些问题的研究进展，提出了今后应深入研究的问题.

Serrated Plastic Flow in a Zr-Based Bulk Metallic Glass During Nanoindentation

We investigate plastic deformation of Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass using depth sensing nanoindentation. Numerous serrations in the load-displacement curves during indentation, shear bands and pile-ups around the indent were observed. The results revealed that the serrated plastic flow behaviour in this alloy depends strongly on the indentation strain rate.

相对性原理及其对自然界定律的协变性要求：机械能守恒定律协变性疑难的解

阐明狭义相对性原理的准确含义，批出它并不要求自然界每条定律都单独协变，但要求每条定律至少属于一个协变集合，给出最小协变集的求法。表明机械能守恒定律满足狭义相对性原理及其对自然界定律的协变性要求，还指出一切社会科学定律也都满足狭义相对性原理。

Thermal mismatch stress in SiC whisker reinforced aluminium composite: new measurement method by X-ray diffraction

A new X-ray diffraction method for characterising thermal mismatch stress (TMS) in SiC_w–Al composite has been developed. The TMS and thermal mismatch strain (TMSN) in SiC whiskers are considered to be axis symmetrical, and can be calculated by measuring the lattice distortion of the whiskers. Not only the average TMS in whiskers and matrix can be obtained, but the TMS components along longitudinal and radial directions in the SiC whiskers can also be deduced. Experimental results indicate that the TMS in SiC whiskers is compressive, and tensile in the aluminium matrix. The TMS and TMSN components along the longitudinal direction in the SiC whiskers are greater than those along the radial direction for a SiC_w–Al composite quenched at 500°C.

Optical fringe multiplication technique with TEM nano-moiré method

In this paper, a nano-moiré fringe multiplication method is proposed, which can be used to measure nano-deformation of single crystal materials. The lattice structure of Si (111) is recorded on a film at a given magnification under a transmission microscope, which acts as a specimen grating. A parallel grating (binary type) on glass or film is selected as a reference grating. A multiplied nano-moiré fringe pattern can be reproduced in a 4f optical filter system with the specimen grating and the prepared reference grating. The successful results illustrate that this method can be used to measure deformation in nanometre scale. The method is especially useful in the measurement of the inhomogeneous displacement field, and can be utilized to characterize nano-mechanical behaviour of materials such as dislocation and atomic bond failure.

Cu原子簇触发形核下的深过冷Ag-Ge合金组织演变研究

采用玻璃包覆的方法获得具有较大过冷度的亚共晶、共晶以及过共晶Ag-Ge合金熔体,并通过高能离子束轰击Cu箔产生Cu原子团簇溅射到过冷合金熔体中来触发非均质形核过程.凝固后合金显微组织的分析结果表明:在深过冷合金熔体中引入Cu原子团簇,它对亚共晶、共晶以及过共晶Ag-Ge合金的显微组织演变有着不同的影响效果,分析了显微组织的演变规律与形成机制. The Ag-Ge alloy melts with deeply undercooled hypoeutectic, eutectic and hypereutectic were obtained via glass fluxing technique. The nucleation of the deeply undercooled alloy melts were triggered by atoms cluster sputtering on the surface of the melts. The atoms clusters were generated by an ion beam bombarding on the Cu foil fixed above the alloy melts. The resultant microstructure reveals that the induced atom clusters exert great influence on the microstructural evolution of the highly undercooled eutectic and hypereutectic Ag-Ge alloys, but no obvious influence on the highly undercooled hypoeutectic alloy. The microstructural evolution and formation mechanism were analyzed and discussed.

湍流计算的多尺度模型与尺度间相互作用规律

湍流计算的多尺度模型把物理（空间）尺度分为大小尺度，大小尺度（LSS）运动微分积分方程组通过湍流应力项相耦合。利用该方程组计算了不可压槽道和平面混合层流动的三维时间演化，同时算出平均流速、最大和平均脉动速度。平均速度和平均脉动速度与NS计算结果一致，NS计算未能算出最大脉动速度。混合层最大脉动速度突增现象与流动转捩猝发现象相对应。LSS方程计算中，小尺度l_(2f)与大小涡分割尺度l_c之比约为1/2～1/4时，数值解很好收敛；l_(2f)/l_c = 1/5未能获得收敛解。解析分析证实：涡尺度介于l_c/3和l_c之间的小涡（称作近程小涡）及介于l_c/2和l_c之间的小涡（定义为共振小涡）分别提供了所有的小涡对大涡作用应力的90%和75%，给出近程小涡和共振小涡作用应力的微分表达式；获得微分形式的大小尺度封闭方程组及大尺度运动封闭方程组。对单向剪切湍流，共振作用应力公式简化为Prandtl混合长理论应力公式。给出初步数值计算结果及湍流多尺度模型基本方程组的一般形式。

A thermal-elastic analysis on laser-induced reverse bulging and plugging in circular brass foil

A new failure mode is observed in circular brass foils induced by laser beam. The new failure is based on the following experimental facts : (1) the peripheries of the circular brass foils are fixed and the surfaces of the foils are radiated by laser beam ; (2) the laser beam used is considered to be non-Gaussian spatially, actually an approximately uniform distribution limited in a certain size spot ; (3) the pulse on time of laser beam should be 250 μs, i.e. so called long duration pulse laser. The failure process consists of three stages ; i.e. thermal bulging, localized shear deformation and perforation by plugging. The word reverse in reverse bulging and plugging mode means that bulging and plugging occur in the direction of incident laser beam. To study the newly-discovered type of failure quantitatively, analytical solutions for the axisymmetric temperature field and deflection curve are derived. The calculated results show that the newly discovered failure mode is attributed to the spatial structure effect of laser beam indeed.

Stability of ZrTiCuNiBe Bulk Metallic Glass Upon Isothermal Annealing Near the Glass Transition Temperature

The stability of Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) upon isothermal annealing near the glass transition temperature has been investigated by using x-ray diffraction, differential scanning calorimetry, and the pulse echo overlap method. The density, elastic constants, and thermodynamic parameters as well as their annealing time dependence have been determined. The microstructural and properties changes of the annealed BMG were checked by acoustic measurement. Obvious structural and property changes were observed with prolonged annealing of the BMG near the glass transition temperature.

“神舟”四号中的流体物理实验

在多年地基研究的基础上，作为载人航天工程应用系统的有效载荷，在我国“神舟”四号飞船返回舱在轨飞行期间进行了大Marangoni数(Ma)液滴热毛细迁移空间微重力实验．实验中FC-75液和．5cst硅油分别为滴相和连续相实验流体介质，研究了在稳定、长时间的微重力环境中，不同温度梯度条件下液滴热毛细迁移的现象及特征．Marangoni数到达5500，很大地扩展了过去液滴热毛细迁移实验的Ma参数范围．实验结果表明，大Ma数液滴热毛细迁移特征规律复杂，迁移速度与YGB模型线性预测有明显的差别．文章介绍了液滴热毛细迁移研究进展，给出了此次空间实验的一些主要结果．讨论了大Ma液滴热毛细迁移的特征，并对自行研制的空间实验设备、实验过程进行了简要介绍．

气相爆轰波在障碍物上Mach反射后流场的分析

详细分析了气相爆轰波在斜劈上Mach反射后的流场。根据胞格结构的烟迹记录，得到了爆轰波Mach反射时三波点迹线与楔面的夹角X与楔角θ的定量关系，依此推算出爆轰波绕射楔块 时从规则反射向Mach反射转变的临界角范围。论文也分析了影响X角和Mach杆后压力的主要 因素。该结果有助于更深入了解爆轰波的本质，也为数值模拟气相爆轰波在障碍物上Mach反射现象提供了可靠的对照依据。