C18_Time_Dependent___2D_Component_Transfer_2

C18_Time_Dependent_ - Time Dependent 2D Component Transfer Applications of isothermal equation of continuity of components Steady state gas

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Time Dependent & 2D Component Transfer Applications of isothermal equation of continuity of components Steady state gas absorption by diffusion into a falling liquid film - Assumption: constant diffusivity, diffusion is negligible in z - Non-zero components: u z , dc A /dz, dc A /dx, dc B /dz, dc B /dx - Balance for component A Recall that 2 max 1 z x uu δ ⎛⎞ =− ⎜⎟ ⎝⎠ 2 * 2 A A z cc uD z x ∂∂ = 2 2 max 2 1 A A x z x ⎡⎤ ⇒− = ⎢⎥ ⎣⎦ with boundary conditions 0 00 0 0 A AA A A A zx x c c N D x == = = =
Background image of page 1

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

View Full DocumentRight Arrow Icon
Time Dependent & 2D Component Transfer Applications of isothermal equation of continuity of components Steady state gas absorption by diffusion into a falling liquid film This equation could be solved using the method of variable combination 0 max 1 4/ A A c xx erf erfc c Dz u =− = The local flux of gas at a given z position on the gas-liquid interface 0 0 0 A AA x x uD c ND c x z π = = ⎛⎞ = ⎜⎟ ⎝⎠ called penetration model Total flux over the interface can also be calculated * . x x Dx t α ⎡⎤ + ∇= ⎣⎦ u
Background image of page 2
Time Dependent & 2D Component Transfer Applications of isothermal equation of continuity of components Dissolution and diffusion from solid surface into a falling liquid film - Assumption: constant diffusivity, diffusion is negligible in z - Non-zero components: u z , dc A /dz, dc A /dx, dc B /dz, dc B /dx - Balance for component A for a short exposure time Due to the coordinate change 2 2 2 2 z gy y xy u ρδ δ μδ ⎛⎞ =− = ⎜⎟ ⎝⎠ 2 2 AA cc ay D zy g a μ ∂∂ = = For the region very close to the surface () 2 2 2 z yy u a y δδ >> = =
Background image of page 3

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

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/01/2011 for the course PGE 312 taught by Professor Peters during the Fall '08 term at University of Texas at Austin.

Page1 / 12

C18_Time_Dependent_ - Time Dependent 2D Component Transfer Applications of isothermal equation of continuity of components Steady state gas

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online