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Convective Derivative

A Derivative taken with respect to a moving coordinate system, also called a Lagrangian Derivative. It is given by

\begin{displaymath}
{D\over Dt} = {\partial\over\partial t}+{\bf v}\cdot\nabla,
\end{displaymath}

where $\nabla$ is the Gradient operator and ${\bf v}$ is the Velocity of the fluid. This type of derivative is especially useful in the study of fluid mechanics. When applied to ${\bf v}$,

\begin{displaymath}
{D{\bf v}\over Dt}= {\partial {\bf v}\over\partial t}+(\nabl...
...\bf v})\times {\bf v}+\nabla({\textstyle{1\over 2}}{\bf v}^2).
\end{displaymath}

See also Convective Operator, Derivative, Velocity


References

Batchelor, G K. An Introduction to Fluid Dynamics. Cambridge, England: Cambridge University Press, p. 73, 1977.




© 1996-9 Eric W. Weisstein
1999-05-26