流速梯度

流速梯度对悬浮颗粒脉动强度的影响

Effect of Velocity Gradient on the Turbulent Intensity of Suspended Particles

理论与实验研究结果表明该方法可消除渡越时间效应、湍流和采样单元内流速梯度造成的频谱模糊。

Theoretical and experimental results show that this method can eliminate the Doppler ambiguity spectra produced by transit-time effect , turbulence and velocity gradient in sample volume .

对两种泥浆的剪切稀释能力究竟应该怎样比较，笔者提出了自己的看法，认为从相同的流速梯度出发比较两种泥浆的剪切稀释能力是没有可比性的。

The author believes , it is rational to compare shear dilution abilities of two kinds of mud identical apparent viscocity .

文章分析了与折冲流有关的因素，如压差、压力和流速梯度以及渥奇面参数，进而提出了修改方案，基本解决了该孔存在的折冲流问题。

The factors related to the oblique flow , such as pressure difference , pressure and velocity gradients and the parameter of Ogee surface are also analysed .

实验结果表明，该方法可消除湍流、渡越时间效应、采样单元内流速梯度和双采样单元内散射粒子互相关性等因素造成的湍谱模糊，实现无模糊湍流测量。

Experimental results indicate that this method can eliminate the Doppler ambiguity spectrum produced by turbulence , transit time effect , velocity gradient in sample volume and correlation of the scatterers in dual sample volume and measure turbulence flow unambiguously .

同时，切应力也不再仅由轴向流速梯度提供，径向流速梯度也将产生切应力，但是在计算管壁切向上的切应力时，径向流速梯度的贡献仍相当小。

Meantime , the shear stress is now caused by the radial velocity gradient as well as the axial velocity gradient , although the contribution to the wall shear stress along the flow directoin of the radial one is relatively small .

从模拟中得到，近岸波浪传播受沿岸流、离岸流的流速和梯度影响时，波高的变化规律。

As a result , the correlation between wave height and the velocity and the gradient of coastal currents was obtained .

从这样的近似解得出的Reynolds剪应力是和平均流速的坐标梯度成正此。

From this approximate solution the shearing component of the Reynolds stress is found to be directly proportional to the gradient of mean velocity .

本文求解局部缓慢扩张动脉管中血液振荡流的基本方程，得到血管内血液的流速与压力梯度的关系。

Through solving the fundamental equations of periodic oscillatory blood flow in local slow expansion artery , the relation between velocity and pressure gradient in the tube was obtained .

借助于提高流速和使用梯度洗脱在其上实现了快速手性分离。采用原位聚合法直接在毛细管柱中合成出具有大孔结构的整体毛细管分子印迹柱。

Rapid chiral separations were achieved on it by combining high flow rate with gradient elution . A cinchonine imprinted monolithic polymer was directly prepared in a fused capillary column by in-situ polymerization .

分析了井身压力、流速、温度梯度、流动阻力的变化，根据注入井、采油井举升结构及各部分的特点，建立了注入井和采油井举升优化模型；

Based on the well bore structure of injection well and production well and the characteristics of every part , the well bore optimization model of injection well and production well is established .

发现液体流速、速度梯度、气泡直径随釜内位置的变化分别可用一次、二次、三次曲线表征。

It has been found that the variation of flow rate , velocity gradient and bubble size with position can be characterized by equations of first degree , second degree and third degree polynomial , respectively .

为了使所得结果便于应用，文章通过管轴向中心线流速与压力梯度之间的关系式，进一步给出一种利用管轴向中心线流速计算管内切应力分布的简便方法。

For clinic application , a convenient method was proposed through the relationship between centerline velocity and pressure gradient that the distribution of blood flow shear stress could be obtained by measuring the centerline velocity in the tube .

蒸气流速对存在温度梯度的竖直壁面Marangoni凝结换热的影响研究

Effect of vapor velocity on Marangoni condensation heat transfer on vertical surface with temperature gradients

结果表明，由于纵向时均流速的垂线分布梯度的作用，颗粒在两个方向上的脉动强度均可能超过相应的流体脉动强度。

It shows that suspended particles exhibit a higher turbulent intensity in both directions than the carrier fluid when the velocity gradient is large .

环空螺旋流是钻井液在钻井作业中常见的一种流型，怎样方便、快速及高精度地计算其流速场与压力梯度是一个重要工程问题。

Helical flow in the annular is a common flow pattern in drilling , and it is an important engineering problem for fast and accurate calculating of the flow field and pressure gradient .

结果表明：洗脱剂浓度、柱操作流速、温度及梯度洗脱对洗脱曲线及回收率有不同程度的影响，果酸洗脱回收最佳条件为：2%NaOH、2BV/h、20℃；

It was shown that the eluant concentration , flow rate and temperature gradient elution influenced elution curves of fruit acid on LSI-1031 anion exchange resin and the reclaim efficiency of fruit acid ; The optimum parameters were : 2 % NaOH , 2BV / h and 20 ℃ .

脊坝及刺坝坝头处流速变化剧烈，形成较大的流速梯度；

Near the head of the fish back and the fish bones , the velocity changes greatly with large velocity gradient .