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-   -   Fluidized Bed Simulation (http://www.cfd-online.com/Forums/cfx/22843-fluidized-bed-simulation.html)

Siaw Khur July 14, 2006 03:31

Fluidized Bed Simulation
 
Hi, I am facing problems in simulating the fluidized bed reactor. Please advise me if anyone has the experience in fluidized bed reactor simulation. Many thanks!

user July 14, 2006 09:10

Re: Fluidized Bed Simulation
 
hi khur,

are you doing gas /solid or liquid/solid fluidisation

with regards user

Siaw Khur July 14, 2006 20:51

Re: Fluidized Bed Simulation
 
Hi there, I am doing gas-solid fluidization. Do you have experience simulating this environment?

Regards, Khur

Info-guy July 16, 2006 16:22

Re: Fluidized Bed Simulation
 
ask star-cd support they have a lot of papers on this (www.cd-adpaco.com)


user July 17, 2006 08:43

Re: Fluidized Bed Simulation
 
hi can u post the problem u have in modeling of gas solid fluidsation

bye

Siaw Khur July 17, 2006 21:45

Re: Fluidized Bed Simulation
 
Hi there, I have failure in my solver. The solver couldn't be run. I defined 2 domains in my simulation in order to divide the solid phase (static bed) and gas phase (fluidizing agent). A separate region was self-generated in my reactor for defining the static bed, however i am not sure that whether the static bed was being defined properly.

By the way, what is your email address? if you wish to send me some CFD information, please send to wkhur@yahoo.com

Below are the messages that i obtained in the solver. +--------------------------------------------------------------------+ | Reference Pressure Information |+--------------------------------------------------------------------+ Domain Group: Domain 2

Pressure has not been set at any boundary conditions. The pressure will be set to 0.00000E+00 at the following location:

Domain : Domain 2

Node : 1 (equation 1)

Coordinates : ( 1.50000E-01, 1.50000E-01, 0.00000E+00).

+--------------------------------------------------------------------+ | Average Scale Information |+--------------------------------------------------------------------+ Domain Name : Domain 1

Global Length = 1.6543E-01

Minimum Extent = 1.5000E-01

Maximum Extent = 4.1000E-01

Density = 1.1850E+00

Dynamic Viscosity = 1.8310E-05

Velocity = 2.5000E-01

Advection Time = 6.6172E-01

Reynolds Number = 2.6766E+03

Domain Name : Domain 2

Global Length = 1.5000E-01

Minimum Extent = 1.5000E-01

Maximum Extent = 1.5000E-01

Density = 1.1850E+00

Dynamic Viscosity = 1.8310E-05

Velocity = 0.0000E+00

+--------------------------------------------------------------------+ | Checking for Isolated Fluid Regions |+--------------------------------------------------------------------+ 4 isolated fluid regions were found in domain Domain 1

If the isolated regions do not have the pressure level set either by the boundary conditions or using a reference pressure equation,you may encounter severe robustness problems.

This situation may have arisen because a domain interface was not properly defined during problem setup. Please carefully check the setup.

The solver will stop now and write a results file. The isolated regions can be visualised in CFX Post by making plots of the variable "Isolated Volumes".

If you are sure that the pressure level is set in each isolated fluid region then you can force the solver to turn off this check by setting the expert parameter "check isolated regions = f".


Siaw Khur July 17, 2006 21:52

Re: Fluidized Bed Simulation
 
Hi Info-guy,

Thanks for your information. I have checked on the website that you've given me. Now still pending for the reply from one of the person that i've contacted. Hope that star-cd's features are more or less similar to CFX's.

Do you have any published papers on how fluidized bed reactor is being simulated in CFD?

Thanks

Phil July 24, 2006 08:36

Re: Fluidized Bed Simulation
 
It sounds like you have some setup problems. There should not be any isolated regions... it means you have spurious walls set up in various places.

When you set up the problem, you should use a single domain rather than multidomains, and use the CEL 'step' function to initialize air/solid regions.

For further help, contacting your local support person is a good idea.

Phil

Siaw Khur July 25, 2006 01:56

Re: Fluidized Bed Simulation
 
Hi Phil,

Thanks. I think i have serious problem in the setup. I have contacted the local support person, but i got no reply from them. I need to get the problem sorted out soon as it affects my research progress. Do you have experience in simulating bubbling fluidized bed? Hope that you can advise me if possible. Many thanks.

Regards, Siaw Khur

germangsilva July 28, 2010 14:43

hello

I'm doing studies of fluidized bed (gas-solid), I'm using cfx11 or 12, and applying LES, but I have great difficulty setting the program cfx, I ask your help, please. my email is germangsilva@gmail.com.


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