TOTAL CROSS SECTION MEASUREMENTS FORELECTRONSCATTERINGONMETHANEBETWEEN1AND50eV

ＴＯＴＡＬＣＲＯＳＳＳＥＣＴＩＯＮＭＥＡＳＵＲＥＭＥＮＴＳＦＯＲＥＬＥＣＴＲＯＮＳＣＡＴＴＥＲＩＮＧＯＮＭＥＴＨＡＮＥＢＥＴＷＥＥＮ１ＡＮＤ５０ｅＶＬｉＴａｉｈｕａＹｅＲｕｉｙｉｎｇＹａｎｇＹｏｎｇＣｅｎｔｅｒｆｏｒＲａｄｉａｔｉｏｎＰｈｙｓｉｃｓ...     

G2 PREDICTION OF THE ENTHALPIES OF FORMATION FOR SOME DIATOMIC CATIONS AND NEUTRALS

Ｇ２ＰＲＥＤＩＣＴＩＯＮＯＦＴＨＥＥＮＴＨＡＬＰＩＥＳＯＦＦＯＲＭＡＴＩＯＮＦＯＲＳＯＭＥＤＩＡＴＯＭＩＣＣＡＴＩＯＮＳＡＮＤＮＥＵＴＲＡＬＳＳｕＫｅｈｅＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｃａｌＥｎｇｉｎｅｒｉｎｇ，ＮｏｒｔｈｗｅｓｔｅｒｎＰｏｌｙ...     

THE EXCESS HEAT EXPERIMENTS ON COLD FUSION IN TITANIUM LATTICE

ＴＨＥ　ＥＸＣＥＳＳ　ＨＥＡＴ　ＥＸＰＥＲＩＭＥＮＴＳ　ＯＮ　ＣＯＬＤ　ＦＵＳＩＯＮ　ＩＮ　ＴＩＴＡＮＩＵＭ　ＬＡＴＴＩＣＥＴＨＥＥＸＣＥＳＳＨＥＡＴＥＸＰＥＲＩＭＥＮＴＳＯＮＣＯＬＤＦＵＳＩＯＮＩＮＴＩＴＡＮＩＵＭＬＡＴＴＩＣＥ￥ＺｈａｎｇＱｉｎｇ...     

RELATIVISTIC CALCULATION OF IONIZATION ENERGIES FOR TITANIUM IONS Ti Ⅰ TO Ti XXII

ＲＥＬＡＴＩＶＩＳＴＩＣＣＡＬＣＵＬＡＴＩＯＮＯＦＩＯＮＩＺＡＴＩＯＮＥＮＥＲＧＩＥＳＦＯＲＴＩＴＡＮＩＵＭＩＯＮＳＴｉⅠＴＯＴｉＣｈｅｎＢｏ１，２ＴａｎＭｉｎｇｌｉａｎｇ２ＪｉａｎｇＧａｎｇ２ＺｈｕＺｈｅｎｇｈｅ２ＺｈａｏＹｏｎｇｋｕａｎ３１Ｉｎ...     

MEASUREMENTS OF Fe AND Cu K-Shell IONIZATION CROSS SECTIONS BY SLOW ELECTRON IMPACT

ＭＥＡＳＵＲＥＭＥＮＴＳＯＦＦｅＡＮＤＣｕＫ－ＳｈｅｌＩＯＮＩＺＡＴＩＯＮＣＲＯＳＳＳＥＣＴＩＯＮＳＢＹＳＬＯＷＥＬＥＣＴＲＯＮＩＭＰＡＣＴＬｉＴａｉｈｕａＡｎＺｈｕＬｕｏＺｈｅｎｇｍｉｎｇＣｅｎｔｅｒｆｏｒＲａｄｉａｔｉｏｎＰｈｙｓｉｃｓ，Ｉｎｓ...     

EFFECT OF RADIAL ELECTRICAL FIELD ON NEOCLASSICAL TRANSPORT IN TOKAMAKS

ＥＦＦＥＣＴＯＦＲＡＤＩＡＬＥＬＥＣＴＲＩＣＡＬＦＩＥＬＤＯＮＮＥＯＣＬＡＳＳＩＣＡＬＴＲＡＮＳＰＯＲＴＩＮＴＯＫＡＭＡＫＳＥＦＦＥＣＴＯＦＲＡＤＩＡＬＥＬＥＣＴＲＩＣＡＬＦＩＥＬＤＯＮＮＥＯＣＬＡＳＳＩＣＡＬＴＲＡＮＳＰＯＲＴＩＮＴＯＫＡＭＡＫＳ￥...     

THE MACQM CALCULATION OF THE TOTAL ENERGY CURVE FOR THE ICOSAHEDRAL CENTRAL STRUCTURE OF THE CLUSTER H_13~-

ＴＨＥＭＡＣＱＭＣＡＬＣＵＬＡＴＩＯＮＯＦＴＨＥＴＯＴＡＬＥＮＥＲＧＹＣＵＲＶＥＦＯＲＴＨＥＩＣＯＳＡＨＥＤＲＡＬＣＥＮＴＲＡＬＳＴＲＵＣＴＵＲＥＯＦＴＨＥＣＬＵＳＴＥＲＨ－１３ＺｈａｎｇＪｉａｎｐｉｎｇ＊ＬｉＰｉｎｇＧｏｕＱｉｎｇｑｕａｎＩｎｓｔ...     

CALCULATION FOR STRETCHING VIBRATIONAL SPECTRUM OF CH_4

ＣＡＬＣＵＬＡＴＩＯＮＦＯＲＳＴＲＥＴＣＨＩＮＧＶＩＢＲＡＴＩＯＮＡＬＳＰＥＣＴＲＵＭＯＦＣＨ４ＣｈｅｎＸｉａｎｇｒｏｎｇＧｏｕＱｉｎｇｑｕａｎＰａｎｇＸｉａｏｆｅｎｇＩｎｓｔｉｔｕｔｅｏｆＡｔｏｍｉｃａｎｄＭｏｌｅｃｕｌａｒＳｃｉｅｎｃｅａｔＨｉｇ...     

会议消息

会议消息ＦＩＦＴＨＩＮＴＥＲＮＡＴＩＯＮＡＬＣＯＮＧＲＥＳＳＯＮＳＯＵＮＤＡＮＤＶＩＢＲＡＴＩＯＮ￥ＵｎｉｖｅｒｓｉｔｙｏｆＡｄｅｌａｉｄｅ，ＳｏｕｔｈＡｕｓｔｒａｌｉａＤｅｃ．１５～１８３１９９７第五届国际声和振动会议将于１９９７年１２月１５～１８...     

GIANT MAGNETO-IMPEDANCE IN Fe-BASED SOFT FERROMAGNETIC RIBBONS

ＧＩＡＮＴＭＡＧＮＥＴＯ－ＩＭＰＥＤＡＮＣＥＩＮＦｅ－ＢＡＳＥＤＳＯＦＴＦＥＲＲＯＭＡＧＮＥＴＩＣＲＩＢＢＯＮＳＣｈｅｎＣｈｅｎＭｅｉＬｉａｎｇｍｏＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＳｈａｎｄｏｎｇＵｎｉｖｅｒｓｉｔｙ，Ｊｉｎａｎ２５０１００...     

Wave-induced bed flows by a Lagrangian vortex scheme

Nominally 2-dimensional viscous flow induced by gravity waves over a spatially periodic bed is simulated by a Lagrangian vortex scheme. A vortex sheet is introduced on the surface at each time step to satisfy the zero velocity conditions. The sheet is discretised; the vortex-in-cell method is used to convect vorticity and random walks are added to effect viscous diffusion. Good agreement with analytical theory is obtained for velocity profiles in uniform sinusoidal flow and for mass transport due to linear waves. Mass transport for finite amplitude waves is also obtained. For separated flow over rippled beds, which is still liminar, a vortex decay factor is required to produce agreement with experiment and is thought to compensate for large scale 3-dimensional effects.     

Modulation of homogeneous shear turbulence laden with finite-size particles

The dynamics of homogeneous shear turbulence laden with spherical finite-size particles is investigated using fully resolved numerical simulations to understand how the presence of particles modulates turbulent shear flows. We focus on a dilute flow laden with non-sedimenting particles whose diameter is slightly smaller than or comparable with those of vortex cores in turbulence. An immersed boundary method is adopted to represent a spherical finite-size particle. Numerical results show that the presence of particles augments the viscous dissipation of turbulence kinetic energy, which leads to a slower increase in the turbulence energy. Although the augmentation of energy dissipation occurs predominantly inside viscous layers surrounding particles in an initial period, the contribution from their outside becomes more significant due to the modification of turbulence structures as turbulence develops. It is found that the particles exhibit weak tendency to accumulate in vortex layers. The particles approaching and colliding with vortex layers induce large velocity fluctuations, which leads to the generation and shedding of thin vortex tubes. Newly generated vortex tubes interact with developed vortex tubes and layers, and modify the entire structure of the vorticity field.     

矩形通道内层流对流换热的最优速度场

针对矩形通道内的层流对流换热问题,通过数值求解速度场协同方程,得到了给定黏性耗散条件下通道内的最优速度场为多纵向涡的流动结构,表明多纵向涡流型可在流阻增加不多的情况下使换热显著强化.通过在通道壁面布置不连续双斜肋,在通道内产生了接近于最优速度场的多纵向涡流动,数值计算结果表明,在Re=1000时,与光滑通道相比,不连续...     

Simulations of single and multiple swimmers with non-divergence free deforming geometries

We present a vortex particle method coupled with a penalization technique to simulate single and multiple swimmers in an incompressible, viscous flow in two and three dimensions. The proposed algorithm can handle arbitrarily deforming bodies and their corresponding non-divergence free deformation velocity fields. The method is validated on a number of benchmark problems with stationary and moving boundaries. Results include flows of tumbling objects and single and multiple self-propelled swimmers.     

Influence of the magnetoelastic anisotropy on the domain wall dynamics in bistable amorphous wires

We deal with the influence of the applied stress on the domain wall velocity in glass-coated magnetic microwires. In general, the domain wall velocity decreases with the applied tensile stress. Four regimes of the domain wall dynamics appear: (1)?diffusion-damped, (2)?a regime with variable domain wall width, (3)?a viscous and (4)?a vortex regime. Detailed analysis of domain wall parameters shows that the structural relaxation plays an important role even at ambient temperatures if high tensile stress is present. At higher fields (viscous regime), the most important damping arises from magnetic relaxation of magnetic moments. Finally, the domain wall velocity steeply increases (reaching a maximum at 7000?m?s(-1)) in the vortex regime and so does the domain wall mobility.     

A fast resurrected core-spreading vortex method with no-slip boundary conditions

To simulate two-dimensional viscous incompressible flows based on a scheme of blob splitting and merging, we developed a vortex method and employed a fast multipole method to speed the computation of velocities. The diffusion of the vortex sheet induced at a solid wall by the no-slip boundary conditions is first modeled according to the analytical solution of Koumoutsakos and then converted into discrete blobs in the vicinity of the wall. To prevent the vorticity from entering the solid body, we introduce a concept residual circulation in a sense that only a partial circulation of the vortex sheet is diffused into the flow field; the rest remains at the wall. Blobs near the wall are thus avoided. Blobs near the wall that might cause large fluctuations in the strength of the vortex sheet are handled similarly. The solver thus developed requires no grid-based remeshing. We applied this solver to simulate the flow induced with an impulsively initiated circular cylinder; the results agree satisfactorily with those of previous experimental and numerical investigations.     

Clustering of the low-inertia particle number density field in random divergence-free hydrodynamic flows

We consider the diffusion of the low-inertia particle number density field in random divergence-free hydrodynamic flows. The principal feature of this diffusion is the divergence of the particle velocity field, which results in clustering of the particle number density field. This phenomenon is coherent, occurs with a unit probability, and must show up in almost all realizations of the process dynamics. We calculate the statistical parameters that characterize clustering in three-dimensional and two-dimensional random fluid flows and in a rapidly rotating two-dimensional random flow. In the former case, the vortex component of the random divergence-free flow generates a vortex component of the low-inertia particle velocity field, which generates a potential component of the velocity field through advection. By contrast, in the case of rapid rotation, a potential component of the velocity field is generated directly by the vortex component of the random divergence-free flow (linear problem).     

涡方法中的粘性效应

涡方法中粘性效应可通过涡的随机移动或改变涡核尺寸两种途径并入。本文侧重讨论后者。用改变涡核尺寸并入粘性的方法计算了Blasius平板同题,并与Blasius解做了比较。     

Acoustic-excited vortex shedding and acoustic nonlinearity at a rectangular slit with bias flow

The acoustical response of a slit with a mean bias flow is numerically studied. By means of a potential flow model based on the discrete vortex method and a spanwise-averaged three-dimensional Green?s function, both unsteady vortical flow and slit impedance are obtained in a unified theoretical framework. The numerical simulation focuses on the acoustic-excited vortex structures of the slit flow while neglecting the viscous damping effect. Three representative flow features are demonstrated, which are the destabilized jet flow, the rolling up of vortex sheets and formation of vortex pairs, and the reversal flow with alternating vortex shedding on both sides of the slit. These features are corresponding to low, moderate, and high sound amplitude, respectively. The acoustic behavior of the slit can be divided into linear, transition, and nonlinear regimes. During its evolution through the three regimes, the resistance exhibits a constant value, a slight decrease, and a significant increase with the increasing sound amplitude. Correspondingly, the reactance first remains constant and then shows a modest decrease as the sound amplitude increases. The nonlinear effect also causes the gradual decrease of the mean bias velocity in company with the marked increase of the amplitude of the fluctuating velocity in the slit. The mean bias velocity decreases to about 80 percent of its linear value at the transition point where reversal flow begins to occur, and further decreases to only 10 percent in the highly nonlinear region. The slit impedance is also presented as a function of frequency and for different aspect ratios. And the effects of frequency and slit geometry are discussed.     

Dynamic behavior of diffusion flame interacting with a large-scale vortex by laser imaging techniques

Instantaneous and simultaneous measurements of two-dimensional temperature and OH-LIF profiles by combining Rayleigh scattering with laser induced fluorescence (LIF) were demonstrated in a nitrogen-diluted hydrogen (H₂ 30% + N₂ 70%) laminar normal diffusion flame interacting with a large-scale vortex by oscillating central fuel flow or in an inverse diffusion flame by oscillating central airflow. The dynamic behavior of the diffusion flame extinction and reignition during the flame–vortex interaction processes was investigated. The results obtained are described as follows. (1) The width of the reaction zone decreases remarkably, and a decrease in flame temperature and OH-LIF is seen with increasing central airflow in an inverse diffusion flame. OH-LIF increases, and temperature does not change with increasing central fuel flow in a normal diffusion flame. The computations predict the experimental results well, and it is revealed that flame temperature characteristics result from the preferential diffusion of heat and species, which induces excess enthalpy or on enthalpy deficit, and an increase or decrease in H₂ mole fraction in the flame. (2) When a large velocity fluctuation is given to the central flow, the temperature and the OH-LIF at the reaction zone become thin at the convex and circumferential part of the vortex where a high temperature layer exists, and the temperature at the reaction zone is lowered in the inverse flame and the normal flame. (3) The width and temperature of the reaction zone interacting with the vortex recover quickly to that of the laminar steady flame after the vortex passing in the normal flame, but the recovery to that of the steady flame after the vortex passing is delayed in the inverse flame. (4) When a remarkably large velocity fluctuation is given to the central airflow in the inverse flame, thinning of temperature and reaction zone starts at the convex and circumferential part of the vortex, resulting in a and flame extinction completely occurs at the tail part of the vortex and makes the pair of edge flames. The outside edge flame reignites and connects with the upstream reaction zone. The inside edge flame finally extinguishes as the supply of fuel is interrupted by the outside edge flame.