For faster navigation, this Iframe is preloading the Wikiwand page for 雷诺传输定理.

雷诺传输定理

雷诺传输定理也称为莱布尼兹-雷诺传输定理雷诺输运定理,是以积分符号内取微分闻名的莱布尼兹积分的三维推广。

雷诺传输定理得名自奥斯鲍恩·雷诺(1842–1912),用来调整积分量的微分,用来推导连续介质力学的基础方程。

考虑在时变的区域积分,其边界为,考虑上式对时间的微分:

若要求上述积分的导数,会有两个问题,的时间相依性,及因动态的边界而增加或减少的空间,雷诺传输定理提供了必要的框架。

通用型式

雷诺传输定理可表为以下形式[1][2][3]是:

其中为向外的单位法向量,为区域中的一点,也是积分变数,是位于的体积元素及表面元素,为面积元素的速度而非流速。函数可以是张量向量标量函数[4]。注意等式左边的积分只是时间的函数,所以采用全微分符号。

针对流体块的形式

在连续介质力学中,此定理常用在没有物质进来或离开的流体块或固体中。若为一流体块,则存在速度函数及边界元素符合下式

上式在替代后,可以得到以下的定理[5]

错误的引用

此定理常被错误的引用为只针对物质体积(material volume)的形式,若将只针对物质体积应用于物质体积以外的区域中,就会出现问题。

特别形式

不随时间改变,则,且恒等式化简为以下的形式

不过若用了不正确的雷诺传输定理,无法进行上述的简化。

在一维下的诠释及简化

此定理是积分符号内取微分的高维延伸,有些情形下可以简化为积分符号内取微分。假设无关,且平面的单位方块,且有的极限,雷诺传输定理会简化为

上述是由积分符号内取微分来的表示式,但x及t变数已经对调。

相关条目

脚注

  1. ^ L. Gary Leal, 2007, p. 23.
  2. ^ O. Reynolds, 1903, Vol. 3, p. 12–13
  3. ^ J.E. Marsden and A. Tromba, 5th ed. 2003
  4. ^ H. Yamaguchi, Engineering Fluid Mechanics, Springer c2008 p23
  5. ^ T. Belytschko, W. K. Liu, and B. Moran, 2000, Nonlinear Finite Elements for Continua and Structures, John Wiley and Sons, Ltd., New York.
  6. ^ Gurtin M. E., 1981, An Introduction to Continuum Mechanics. Academic Press, New York, p. 77.

参考资料

  • L. G. Leal, 2007, Advanced transport phenomena: fluid mechanics and convective transport processes, Cambridge University Press, p. 912.
  • O. Reynolds, 1903, Papers on Mechanical and Physical Subjects, Vol. 3, The Sub-Mechanics of the Universe, Cambridge University Press, Cambridge.
  • J. E. Marsden and A. Tromba, 2003, Vector Calculus, 5th ed., W. H. Freeman .

外部链接

  • Osborne Reynolds, Collected Papers on Mechanical and Physical Subjects, in three volumes, published circa 1903, now fully and freely

available in digital format:Volume 1, Volume 2, Volume 3,

{{bottomLinkPreText}} {{bottomLinkText}}
雷诺传输定理
Listen to this article

This browser is not supported by Wikiwand :(
Wikiwand requires a browser with modern capabilities in order to provide you with the best reading experience.
Please download and use one of the following browsers:

This article was just edited, click to reload
This article has been deleted on Wikipedia (Why?)

Back to homepage

Please click Add in the dialog above
Please click Allow in the top-left corner,
then click Install Now in the dialog
Please click Open in the download dialog,
then click Install
Please click the "Downloads" icon in the Safari toolbar, open the first download in the list,
then click Install
{{::$root.activation.text}}

Install Wikiwand

Install on Chrome Install on Firefox
Don't forget to rate us

Tell your friends about Wikiwand!

Gmail Facebook Twitter Link

Enjoying Wikiwand?

Tell your friends and spread the love:
Share on Gmail Share on Facebook Share on Twitter Share on Buffer

Our magic isn't perfect

You can help our automatic cover photo selection by reporting an unsuitable photo.

This photo is visually disturbing This photo is not a good choice

Thank you for helping!


Your input will affect cover photo selection, along with input from other users.

X

Get ready for Wikiwand 2.0 🎉! the new version arrives on September 1st! Don't want to wait?