CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT

Microwave drying modeling

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 8, 2010, 15:25
Default Microwave drying modeling
  #1
New Member
 
Join Date: Jun 2009
Posts: 11
Rep Power: 17
jpcfd is on a distinguished road
Hi,

Im trying to simulate the drying by microwave of different buildings material. A multiphysic problem with, electromagenetic, thermal and mass transfer coupled.
I treat the EM with a lambert law of energy penetration depending on the pemeabilty coupled with the moisture. The mass transfer i use a solid domain with liquid-vapour phases one attached and another (vapour) transported with a UDS diffusive equation.

I used a arrenious law to coupled the two phases ratio exchange and the traditional vapour saturation pressure with the desorption isotherm to calculate the quasistacionary equilibrium in each time step.

All is coupled in a multiple UDF schema.

I have detected from the diffusivity values obtained from the literature that i obtain overestimated drying times. The diffusivity value in the material pannel is in kg/m-s instead of m2/s, this mean that the diff coef is multiplied by the density?

I know that the transient term in the scalar transport equation is multiplied by the density but no the diffusive term.

I remake my calculations with the diffusive coefficent multiplied by the density and i obtain pretty close to the reality values. Also i check this on CFX that use traditional m2/s units.

Can any one explain this?

Thanks in advance.
jpcfd is offline   Reply With Quote

Reply

Tags
microwave


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
May Focus Area: Turbulence Modeling Jonas Larsson CFD-Wiki 0 May 2, 2006 12:48
Modeling drying in porous media Oliver Main CFD Forum 0 January 14, 2005 12:41
complex (?) drying modeling: diffusion/multiphase kilroy FLUENT 0 July 7, 2003 04:57
Modeling Flow/Saturation/Absorption in Fibers Gene Dougherty Main CFD Forum 0 June 6, 2003 15:49
CFD Modeling of Two-phase Flow in Small Dia.Tubes Eric Poindexter Main CFD Forum 2 September 22, 2000 10:21


All times are GMT -4. The time now is 18:44.