Turbulence lecture 12

# Turbulence lecture 12 - Turbulence Lecture 12 Energetics...

This preview shows pages 1–3. Sign up to view the full content.

Turbulence Lecture 12 Energetics (of the mean flow) Multiply the mean momentum equation by U , and, contract . i i () 22 2 ii jj i i j UU P U S txx x ρρ µ ∂∂∂ ∂ j i j u u ρ += + − ∂∂∂ 2 2 i j j ij i i i j i j ij ij ij U U U P SU U uu uu S S S tx x ρµ   ∂∂ + +     ±²²²³²²²´ time rate of change of KE mean flow pressure work viscous of following the mean flow Note: i j i i j i j U u U u u u u Uu x xx =− symmetric j Note: 2 ji i j i i j UP US Uuu x µρ −+ ±²²²²²²³²²²²²²´ j Spatial distribution of mean flow KE due to pressure, viscosity, and Reynolds stresses iji j - loss (sometimes gain) of mean flow KE to turb KE 2 ij ij SS - rate of loss of mean flow KE to internal engery. Note: j i U µµ = i j S 2 i ij j U S x {} N 2 2 i j i i j j V i j i i j j A Uuu dV x Uuu ndP + of boundary Unit normal of C.V.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
0 = for most B.C.’s Except for example wind water waves where pressure can do work on surface.
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 06/07/2011 for the course EGM 6341 taught by Professor Mei during the Spring '09 term at University of Florida.

### Page1 / 5

Turbulence lecture 12 - Turbulence Lecture 12 Energetics...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online