
n. 紊流脉动;紊动
A numerical model for turbulent fluctuation and diffusion of gas-particle flows is presented.
本文提出了气固两相流动的湍流扩散数学模型。
The results show that, the influences of turbulent fluctuation on time-averaged infrared signal in different wave band are different.
分析结果表明,在不同的探测波长上,湍流脉动引起的时均辐射信号变化不同;
The statistical analysis of turbulent fluctuation signals can be divided into two categories, large amount sample analysis and local time-frequency analysis respectively.
湍流脉动信号的数理统计可分为大样本统计和局部时频分析。
Turbulent fluctuation affects flow field parametersremarkably in a relatively short distance after transition point, but the effects get weaker quickly downstream;
在转捩点后较近距离内湍流脉动影响较大,随着向下游流动脉动影响迅速减弱;
The dynamical basis of vortex motion solution is the set of equations of turbulent velocity fluctuation.
求涡旋运动解的动力学的基础是湍流速度涨落方程。
Using these formulas and a 1-D LDA, mean square value of 2-D turbulent velocity fluctuation and Reynolds shear stress have been measured for water flow in a square duct.
用这些公式和一台一维激光多普勒测速计,测量了方形管道中水流的二维湍流速度脉动的均方值和雷诺切应力。
The properties of turbulent effects including intensity fluctuation, beam spread, spot quiver, and pathlength fluctuation of laser propagating through a folded Path are discussed.
本文讨论激光在折叠光路上传输时强度起伏、光束扩展、光束抖动和光程长度起伏等湍流效应的性质。
A general expression of the scintillation index is proposed for optical wave propagating in turbulent atmosphere under arbitrary fluctuation conditions.
提出了任意起伏条件下湍流大气中光波闪烁方差的通用表达式。
The statistical characteristics of the laser log-intensity fluctuation and beam pattern in a turbulent atmosphere were stu***d systematically.
我们系统地研究了激光在湍流大气中的光强起伏与光斑统计特征。
Based on turbulent kinetic energy and the rate of turbulent dissipation transport equations, the equation to calculate variance of the refractivity fluctuation is modeled.
根据湍流的动能和动能耗散率输运方程,建立了折射率起伏方差的计算模型。
Measures the time mean velocity and velocity fluctuation using a hot film anemometer with different confinement ratio for the axisymmetric turbulent jet in a dead-end tunnel.
介绍了采用热膜流速仪量测堵头管中不同受限度轴对称射流的时均流速和流速脉动。
Results show that fluctuation amplitudes of all the measured parameters in laminar jets are much smaller than those in turbulent ones.
结果显示层流等离子体射流各参数的波动幅度远小于湍流射流的对应值;
n.|turblence;紊流脉动;紊动
“turbulent fluctuation”是由流体力学领域延伸至多学科的专业术语,其含义可从词源和学科应用两方面解析:
1. 词源解析
2. 学科应用
该术语的跨学科应用体现了其核心特征:非线性、不可预测性和能量传递特性。在工程领域,相关研究常涉及纳维-斯托克斯方程中的雷诺应力项: $$ frac{partial u_i}{partial t} + u_j frac{partial u_i}{partial x_j} = -frac{1}{rho}frac{partial p}{partial x_i} + u frac{partial u_i}{partial x_j} - frac{partial overline{u_i'u_j'}}{partial x_j} $$ 式中最后一项即为湍流脉动引起的动量输运。
“Turbulent fluctuation”是一个流体力学领域的术语,通常用于描述湍流(紊流)中流体物理量的随机、不规则变化。以下为详细解析:
Turbulent(湍流的/紊动的)
指流体运动中存在强烈涡旋、混合和不规则性的状态,常见于高速流动或复杂边界条件(如河流、大气湍流)。其物理特性包括能量级联和动量交换。
Fluctuation(脉动/波动)
表示物理量(如速度、压力、温度)随时间或空间的无规则随机变化。例如,电压波动或经济波动均属于此类现象。
该术语特指湍流中流体参数的瞬时随机变化,如速度、压力等物理量的高频振荡。这种脉动是湍流区别于层流的核心特征,通常通过统计方法(如均方根值)量化分析。
湍流脉动的能量分布符合Kolmogorov尺度律,数学上可通过纳维-斯托克斯方程描述: $$ frac{partial mathbf{u}}{partial t} + (mathbf{u} cdot abla)mathbf{u} = -frac{1}{rho} abla p + u abla mathbf{u} $$ 其中速度场$mathbf{u}$的瞬时值可分解为平均值$overline{mathbf{u}}$与脉动量$mathbf{u'}$之和($mathbf{u} = overline{mathbf{u}} + mathbf{u'}$)。
提到“紊流脉动是流体极不规则运动的体现”,而指出“电压波动与湍流脉动同属随机波动现象”。
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