C4_Isothermal_Equations_of_Change_1

# C4_Isothermal_Equations_of_Change_1 - Equations of Change...

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

Equations of Change for Isothermal Systems The equation of continuity Mass balance over a fixed elementary volume () xx x yy y zz z xyz t yz u u xz u u xy u u ρ ρρ ΔΔΔ ⎡⎤ =Δ Δ ⎣⎦ +Δ Δ ⎢⎥ ( ) . y u uu tx y z ⎛⎞ ∂∂ ⎜⎟ =− + + =− ∇ ⎝⎠ u ( ) is called divergence of , and for incompressible fluids .0 ∇∇ = Mass influx (inward arrows) Mass outflux (outward arrows) x y z x y z

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

View Full Document
Equations of Change for Isothermal Systems The equation of continuity Mass balance over a moving elementary volume () ( ) ( ) ( ) D .. . tD t t ρ ρρ ∂∂ =− ∇ =− ∇ + + ∇ =− ∇ ⎡⎤ ⎣⎦ uu u u u is called material (also, substantial/particle) derivative is called local rate of change of at a given point D/ / Dt t u is called convective (or advective ) derivative, which is the change of as a result of convection of the particle from one location to another where is different ( ) Df .
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 5

C4_Isothermal_Equations_of_Change_1 - Equations of Change...

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

View Full Document
Ask a homework question - tutors are online