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rst1993 January 19, 2015 06:23
Entropy waves
 
Can anyone pls explain what are entropy and vorticity waves? how are they different from acoustic waves?

FMDenaro January 19, 2015 07:29
Quote:
Originally Posted by rst1993 (Post 528121)
Can anyone pls explain what are entropy and vorticity waves? how are they different from acoustic waves?

From the analysis of the Euler equations, the eigenvalues and eigenvectors analysis say that iso-entropic as well as omo-entropic flows have an entropy wave associated to the second eigenvalue u (convective velocity).
That means that along the characteristic curves dx/dt=u you have constant entropy

rst1993 April 23, 2015 03:50
Quote:
Originally Posted by FMDenaro (Post 528132)
From the analysis of the Euler equations, the eigenvalues and eigenvectors analysis say that iso-entropic as well as omo-entropic flows have an entropy wave associated to the second eigenvalue u (convective velocity).
That means that along the characteristic curves dx/dt=u you have constant entropy
But I don't understand that why is the first and second mode of LEE are called vorticity and entropy waves.

FMDenaro April 23, 2015 04:35
Quote:
Originally Posted by rst1993 (Post 543330)
But I don't understand that why is the first and second mode of LEE are called vorticity and entropy waves.

check for Riemann invariants in some textbooks (Zucrow or LeVeque for example)


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