查询词典 vortex flow

By using several thousands of point vortices and small space mesh, we obtain the large scale discrete vortices on the vortex sheet as result of the pairing of small point vortices, thus simulate the instability phenomena of the rolling-up vortex sheet.

由于使用了数千个点涡和较小的空间网格，获得了前缘涡层小涡配对出现的较大的离散涡，模拟了紧卷涡层的不稳定现象。

In present paper a three-dimensional discrete vortex filament method is put forward to simulate the motion and bubble entrainment of an inviscid,incompressible vortex ring .

本文发展了三维离散涡模型用于模拟无粘不可压缩涡环的发展及其与气泡的相互作用，涡环被离散为平均分布在其中心线上的球形涡元，由Biot-Sarvart定律叠加每个涡元的诱导速度得到涡环的运动速度。

The numerical results were in good agreement with the measured results. The experimental and numerical results show that the vortex ring was induced by baroclinic effect and Helmholtz instability in the vicinity of the thruster exit after the donation wave exhausted the tube. The intensity, shape and location of the suspended shock varied when the shape of the vortex ring changed.

爆轰波溢出爆轰管后，斜压效应和Helmholtz不稳定导致涡环的产生，同时在流场中形成止于涡环的悬吊激波，涡环形状的变化又引起悬吊激波的强度、形状和位置的变化。

The analysis shows that with given grid size higher accurate difference scheme can give higher resolutions with wider range of scales, or with given accuracy large grid size can be used for the higher accurate difference scheme. The second part is the numerical simulation of two-dimensional axisymmetric jet. The simulation results show the structure in the near field and the initial transition. In the near field, Kelvin-Helmholtz instability leads to the formation of vortex ring, and nonlinear growth leads to the merging of vortex ring. This is the main instability form. Under the assumption of axisymmetry and two-dimensional computing conditions, the results are applicable only in the near field.

第二部分采用高精度的差分格式对二维轴对称射流进行了数值模拟，模拟结果显示了射流流场结构和涡结构的发展过程，在射流流场近区，K-H失稳导致涡环的产生以及非线性效应的增长导致涡环的对并是射流失稳的主要形式；分析指出在轴对称假设下的射流数值模拟只适用于射流近区的分析。

Streamwise vorticity, which forms in the braid zones where small three-dimensional perturbations grow strongly because of the extensional strain formed by vortex ring, collapses into counter-rotating round vortex tube.

辫子区内小扰动在涡环形成的拉伸应力的作用下快速增长，形成流向涡结构，并不断增强形成流向涡管。

In some species, the leading edge vortex spirals out towards the tip of the wing, while in others there appears to be no spanwise movement of the vortex.

在一些物种，前缘涡的螺旋出对小机翼，而在其他国家似乎没有展运动的旋涡。

This source term model helps to predict the velocity and vortex fields in consistent with a full gridded vane vortex, hut the grid number reduces by 65%.

源项模型可以得到与全网格数值模拟基本一致的诱导速度场和涡量场，而网格量减少了65%。

WIG craft ; wingtip vortex ; downwash angle ; induced drag ; numerical simulation ; ideal vortex model

地效飞行器；翼尖涡；下洗角；诱导阻力；数值模拟；理想涡模型

Experiments of flow conductivity closure stress of typical propping agent are done, propping agent short-term flow conductivity alteration index is defined, by this, the relation between fissure short-term flow conductivity and closure stress, it is close to exponential relation. 4. Establishing the mathematical simulator of hydraulic fractured well's production in a steady state, finding the relation curve between dimensionless flow conductivity and fracture penetration coefficient by means of calculation and analyses, it is the basis of hydraulic fracture. 5. Expatiating the importance of optimized hydraulic fracturing design in reservoir engineering, advancing the optimizing design method, fracture dimension can be calculated easily when the physical parameters are known. 6. Production rate decline standard curve of vertical fractured wells is achieved by mathematical simulation, when the flow pressure is certain , by asymptotic analyze, this decline curve is close to exponential relation.

完成了国内外典型支撑剂的导流能力闭合应力影响实验，在数据分析中定义了支撑剂短期导流能力变异系数，并由此发现裂缝短期导流能力随闭合应力变化的近似符合指数关系式； 4 建立了一种水力压裂井稳态产能的数学模拟器，计算分析找到了最优无量纲导流能力与裂缝穿透比之间的新型关系曲线，它是水力压裂优化设计的基础； 5 阐述了水力压裂油藏工程优化设计的重要性，提出了优化设计方法，在已知支撑剂物性参数条件下可简洁计算最优裂缝尺寸； 6 数学模拟给出了垂直裂缝井产量递减标准曲线，在井底定压条件下通过渐近分析表明，该递减曲线满足指数关系式。

The paper conducts special analysis upon the current status of new product development in the Coco Palm Group, considering the characteristics and applicable conditions of three modes (sequent product development flow, stage-based product development flow and hopper-like product development flow) used in current product development flow, the paper establishes a new production development flow for the Coco Palm Group.

本文着重对椰树公司的新产品开发的现状进行了分析，并结合现今产品开发流程的三种模式（顺序式产品开发流程，阶段门式产品开发流程及漏斗式新产品开发流程）的特点和适用条件，构建了椰树公司新的产品开发流程。

Chinese traditional virtue is humility and wariness,the compliment and praise to the others should be declination

中国人的传统美德是谦虚谨慎，对别人的恭维和夸奖应是推辞。如

We bought this house on the never-never.

我们以分期付款的方式买下这座房子。