相对粗糙度

另外，在计算内螺纹管的压降时，应用了Churchill模型得出的摩擦系数及一个合适的相对粗糙度来修正光管的压降关联式。

In addition , Pressure drop correlations for plain tubes were applied to micro-fin tubes by using a friction factor calculated by the Churchill model and a suitable relative roughness .

结果表明：FRP材料与粒状材料界面的剪切性能，与法向应力的大小、相对粗糙度（表面粗糙度/颗粒的平均粒径）、砂体的初始密度、颗粒的棱角度有关；

Tests showed that the interface shear behavior between FRP composites and granular materials depended on the relative roughness ( surface roughness / particle mean size ), the normal stress level , the initial density of the soil mass , and the angularity of the particles .

管内湍动流体摩擦因数是雷诺数和相对粗糙度的二元非线性函数，由Colebrook隐式方程计算摩擦因数要用迭代的方法求解，很不方便。

The friction factor for the turbulent flow in pipes is the binary nonlinear function of Reynolds number and relative roughness . Calculating friction factor by implicit Colebrook equation have to use iterative algorithm , which is discommodious .

而且由于尺度的减小使得微细通道通常具有较大的相对粗糙度，且其中的流动一般为层流。

Microchannels are commonly characterized by higher relative surface roughness and inner laminar flow .

相似通风机流道表面相对粗糙度对其流动效率的影响

The Influence to Hydraulic Efficiency by Relative Roughness on Surface of Flow Channel in Similar Fans

截面流速随着相对粗糙度的增加非线性减小，但减小趋势变缓。

Section speed of flow reduces along with the relative roughness increase non-linearity and the tendency to change reduces .

渗流量与相对粗糙度也存在两种相反的关系：正相关和负相关关系。

Similarly , there are also two opposite relations between seepage discharge and relative roughness : positive and negative relations .

实验同时发现，壁面相对粗糙度对流动的影响程度随着雷诺数、截面尺寸的增大而有减小的趋势。

It was also found that the effect of the relative roughness was reduced when the size and Re increased .

提出了最大潮流速铅直分布与相对粗糙度参量的关系。

The relationship between the vertical distribution of the maximum tidal current and the relative roughness parameter and its applications have also been studied .

计算结果表明：影响流场结构的主要因素为相对粗糙度和粗糙曲线的空间波数。

The computing results show that the main factors affecting the flow pattern are relative roughness and spatial wave number of wall rough curve .

若流线型物体表面的摩擦阻力系数仅为相对粗糙度的函数，则形状阻力系数与雷诺数无关。

Since if the frictional resistance coefficient is a function of relative roughness , then the form resistance coefficient is independent of the Reynolds number .

相对粗糙度增加时压力与截面流速线的斜率减小，截面流速不易受压力变化的影响。

The line slope of pressure to the section speed reduces which means section speed of flow is not easily influenced by the pressure as relative roughness increases .

当保持相对粗糙度不变，减小空间波数时，流函数扰动峰值和流场受扰区域都将增大；

If the relative roughness keeps constant and the spatial wave number decreases , both the peak of disturbed stream function and disturbed area in flow field increase simultaneously .

利用改进的直剪仪进行了砂土与结构物的接触面剪切试验，研究了不同接触面相对粗糙度对接触面物理力学性质的影响；

A series of soil-structure shear tests was performed by improved direct shear apparatus , and the effect of different relative roughness on mechanical characteristics of interface was studied .

计算结果表明，壁面相对粗糙度、壁面波数（或粗糙元间距）以及Re数是影响流动和摩擦阻力的三个主要因素。

The computing results show that the main factors affecting the flow regime are relative roughness , spatial wave number ( rough element interval ) of wall rough curve and the Reynolds number .

从众多文献研究来看，微通道内的流动与传热与常规尺度通道有很大不同，一个很重要的原因来自于壁面相对粗糙度对流动和换热的影响。

However , existing published results of flow and heat transfer in microchannels show that there is a great deal of discrepancies between classical values and experimental data , surface relative roughness is a main factor account for these differences .

实验结果表明，即使在较小的相对粗糙度高度下，由于微通道中的粗糙度分布密集，会极大地增加流动阻力，这是导致文献中微通道流动阻力系数实验值相互偏差的主要原因之一；

The experimental results show that the surface roughness increases the flow resistance significantly even though the relative height is rather small . This is one of the major factors which causes the disagreements on the friction factor of microchannel flow in the literature ;

具有减反性质的粗糙表面具有两个主要特征：表面具有相对较大的粗糙度；经表面反射后能流分布在较宽广的角度范围。

It is indicated that surfaces with lower reflectance possess two major features : larger roughness and scattering into a wide angle range .

模拟分析了大气稳定度等级、空气相对湿度及地表粗糙度对LNG泄漏事故后果的影响。

Simulation research focused on how the consequence of LNG leakage accidents will be influenced by the atmospheric stability , relative humidity ( RH ) of the atmosphere , and surface roughness .

研究结果表明，冰盖下水流的纵向流速在流动核心区并不遵循对数分布规律，同时揭示了冰盖底部与河床的相对粗糙比、河床相对粗糙度及雷诺数对流速分布规律的影响。

The results reveal that the sectional velocity distribution deviates from the logarithmic law in the core flow area . Meanwhile , the influence of roughness ratio of ice-cover bottom to bed , bed relative roughness and Reynold number on velocity distribution pattern is indicated .