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-   -   Gallalian Invariance -------Again (https://www.cfd-online.com/Forums/main/9344-gallalian-invariance-again.html)

 David Liu June 17, 2005 04:43

Gallalian Invariance -------Again

The first law of thermodynamics is a basic law. But it does NOT obey Gallalian Invariance.

This is because it deals with the kinetic energy which is not of Gallalian Invariance.

This law: W+Q=(K2+P2)-(K1+P1)

W: work; Q: Heat input/out to the system; K: kinetic energy; P: potential energy.

You will find that the work needed is different in two inertia frame if you increase the total energy in same amount for a system.

 versi June 17, 2005 08:07

Re: Gallalian Invariance -------Again

K, the kinetic energy, is interpreted as from random thermal motion of molecues, it does not = (thermal velocity + velocity of inertial frame)^2 /2. by this interpretation, work in two different inertia frame is the same.

 David Liu June 20, 2005 01:01

Re: Gallalian Invariance -------Again

Re: Gallalian Invariance

Posted By: David Liu Date: Sun, 19 Jun 2005, 10:58 p.m.

In Response To: Re: Gallalian Invariance (Tom) ================================================== == Is NS equation of Galilean Invariance? ================================================== ==

For steady flow, NS equation in Vector form: