[abhijeet]

sorry bro....i am not understand your problem....so please define it clearly....

[abhijeet]

Originally Posted by abir dz

thank you sir l tried and it worked .but I have another problem.when I draw the polarisation curve I have falling in curent density at the voltage 0.6v next it augment in 0.7 after that it work normally
it mean why the value of current density deacrease at 0.6 v after that increase
thank you sir

sorry bro ...i am not understand your problem...so define it clearly....

[abir dz]

Originally Posted by abhijeet

sorry bro ...i am not understand your problem...so define it clearly....

hello sir
l work on the three dimensional computational fluidic dynamics modeling of PEM fuel cell
I study the effect of the inlet pressure on the current density.and to draw the polarisation curve of fuel cell it should show the relation between the Vcell and current
my work is normally it work very good but I have problem in Vcell=0,6 the current density deacrease a lot and after that it work normally
I mean why the current density fall and deacrese a lot in V cell =0.
is the work correct and it work normally or the is a mistake
thank you

[abhijeet]

Originally Posted by abir dz

hello sir
l work on the three dimensional computational fluidic dynamics modeling of PEM fuel cell
I study the effect of the inlet pressure on the current density.and to draw the polarisation curve of fuel cell it should show the relation between the Vcell and current
my work is normally it work very good but I have problem in Vcell=0,6 the current density deacrease a lot and after that it work normally
I mean why the current density fall and deacrese a lot in V cell =0.
is the work correct and it work normally or the is a mistake
thank you

sorry bro...i have not much more idea in this area....but do one thing... if possible send me send me the details of your project related to icem and fluent ...and i am trying to solve your problem....

[abir dz]

Originally Posted by abhijeet

sorry bro...i have not much more idea in this area....but do one thing... if possible send me send me the details of your project related to icem and fluent ...and i am trying to solve your problem....

please sir tell me exactly where I can send you the work

[abhijeet]

Originally Posted by abir dz

please sir tell me exactly where I can send you the work

abhijeet190291@gmail.com

[rajann_786]

First, you should check your mesh. If the mesh is bad or ratio is too high, the solution will be divergent and you will get AMG error.

[abir dz]

the mesh is Good and all the parameters are perfect

Sent from my SM-J700H using CFD Online Forum mobile app

[Lokesh Raj]

Hey abir, how is it going?. I have had the same issue with amg solver: w-swirl. It does not matter how your mesh is but a little fine should be good enough. I have a question for you, how are you importing you geometry for analysis ?.

[hellsblade.91]

On what basis does one decide to reduce the value of which URF in Fluent for eg when using k epsilon should i resude trubulence or the dissipation rate or another parameter or the value of the equation which is diverging in the residuals .

Also how does this affect my results

[ViLaks]

Hi Everyone,

First of all sorry for restarting the thread.

I am working with simulation of air flow through an airconditioning outdoor unit panel, with condenser coil. Fan I have modelled using MRF. My mesh size is 4,000,000 cells and 0.97 skewness. My aim is to estimate the airflow (CFM) delivered by the fan.

The problem works fine. I got result matching within 5% wrt experiments.

The problem is, while running, I initially ran the problem in Fluent -13 using standard initilaization and the case completed. But, if I run the same case in Fluent-17 , I get AMG solver divergence: Temperature in the first iteration itself. But if I run in Fluent -17 using Hybrid initialisation, the case runs. Could someone explain what is the problem with Fluent -17??


Thanks

[iyidaniel@yahoo.co.uk]

Originally Posted by Sachin Kulkarni
;125190

Hi,

Try to change the multigrid cycle for pressure from "V" to "W".

Hi Sachin Kulkarni,

I am having a similar problem with the choice of the multigrid cycle. Please, why changing the multigrid cycle for pressure from "V" to "W" for the 3D ROTATING/ SWIRL flow inside the pipe?

[Rajan Bhandari]

When I used inlet BC's as velocity-inlet and outlet BC's as pressure outlet, no error takes place. But when I changed outlet BC's to velocity-inlet, the divergence error occured. Why is that so?

[ViLaks]

Originally Posted by Rajan Bhandari

When I used inlet BC's as velocity-inlet and outlet BC's as pressure outlet, no error takes place. But when I changed outlet BC's to velocity-inlet, the divergence error occured. Why is that so?

Are you sure you changed the outlet boundary condition to velocity intlet??? If ya, then obviously it will diverge because you had given an inlet at the outlet.

[inderjeet426]

Hello everyone, I am working vertical axis wind turbine. I have designed fine 2d model in SW and now trying analyse it's flow analysis. But I am facing convergence problem from many days. My solution residual is not going down to 10-3. My meshing skewness ratio 0.83, orthogonal quality 1., aspect ratio 93.