[mukut]

This is a forum and place of discussion. But, most of the tread still blank and no comments. Please share your suggestion. I have submit some of my problem but response is not good. Please reply.

I wanna simulate the body force of a flow induced by plasma actuator. How is it possible in phoenics? Is there any sample q1 in the phoenics library??? Please help me

[Linh.Hoang]

Hi Mukut,
your Problem is very specific. What are your problems exactly? Be more specific. Have you problems by modelling the plasma or don´t you know how to calculate the forces on a body?
I´m not familiar with flow induced by plasma actuator, not even knowing what a plasma actuator is. Maybe the community can help by solving your problems step by step, when you ask more specific!

Linh

[mukut]

I have already started experiment and collects data using single Dielectric Barrier Discharge plasma actuator.Experimental setup looks like as follow. I need to make






setup in the phoenics domain and find out velocity, body force etc

[soumendu.banik]

Hi!!,
I am trying to model the effect of DBD based plasma actuator for my Thesis. Does anyone have any clue on how to accomplish this in Fluent or for that matter how to estimate the body force based on the specs of the DBD.

Regards

Soumendu

[mukut]

No one give idea or at least any suggestion. I am really surprised, what kind of discussion group is it? If the experts do not help or give suggestion to the newcomer, how can it be fruitful? Please give suggestion and advice.

[gallant77_cfd]

Originally Posted by mukut

No one give idea or at least any suggestion. I am really surprised, what kind of discussion group is it? If the experts do not help or give suggestion to the newcomer, how can it be fruitful? Please give suggestion and advice.

Hi MuKut,

How do you simulate the electrical field as well as plasma field in PHOENICS ? Do you use PHOENICS-CVD? What is the function formula of the body force ?

Best regards
Richard

[mukut]

Dear Richard!

Thanks for knocking. What is phoenics-CVD? I am trying to simulate both electrical and plasma field. [IMG]file:///C:/DOCUME%7E1/mukut/LOCALS%7E1/Temp/moz-screenshot.png[/IMG]
Above pic shows the solution domain (I am trying to make such type of domain in phoenics, I have taken it from a research paper and the author used FLUENT for simulation). The body force eqn. as stated in figure. According to figure, in the doamin I have to insert a bottom electrode in the dielectric material, but how can I make it??

Till now I am trying to make such domain....using a simple boundary condition to calculate electric potential(but I need 2nd order eqn as B. condition [check the thread link])....In my created domain there is only dielectric and upper domain contains air (like pic), but how can I define upper and bottom electrode.........still crawling...
Can you please give me some suggestion plz??

Thnx

Please check this thread also (http://www.cfd-online.com/Forums/pho...-phoenics.html)

[gallant77_cfd]

Hi Mukut,

The PHOENICS-CVD is the special purpose version of PHOENICS which is used for chemical vapor deposition process in semi-cond. or optoelectronics industries. It's function includes plasma simulation.(used for plasma enhanced CVD) You can directly use this module and should be easier rather than you develop the user subroutine for electrical field as well as plasma field (including electrons density, ions density as well as electrons temperature and ion temperature). You can see the introduction of PHOENICS-CVD from this link
http://www.cham.co.uk/DOCS/cham_product_update_CVD.pdf
And the body force is dependent on the electrical field, you shall calculate the electrical field at first and then set the momentum force as the function of electrical field.
Use the command
patch(bdfc, volume, 0, 0, 0, 0, 0, 0, 1, lstep)
(source of u1 at bdfc is f(e) with fixv)
(source of v1 at bdfc is f(e) with fixv)
(source of w1 at bdfc is f(e) with fixv)
where f(e) is the function of electrical field potential

[mukut]

Originally Posted by gallant77_cfd

Hi Mukut,

The PHOENICS-CVD is the special purpose version of PHOENICS which is used for chemical vapor deposition process in semi-cond. or optoelectronics industries. It's function includes plasma simulation.(used for plasma enhanced CVD) You can directly use this module and should be easier rather than you develop the user subroutine for electrical field as well as plasma field (including electrons density, ions density as well as electrons temperature and ion temperature). You can see the introduction of PHOENICS-CVD from this link
http://www.cham.co.uk/DOCS/cham_product_update_CVD.pdf
And the body force is dependent on the electrical field, you shall calculate the electrical field at first and then set the momentum force as the function of electrical field.
Use the command
patch(bdfc, volume, 0, 0, 0, 0, 0, 0, 1, lstep)
(source of u1 at bdfc is f(e) with fixv)
(source of v1 at bdfc is f(e) with fixv)
(source of w1 at bdfc is f(e) with fixv)
where f(e) is the function of electrical field potential

Dear Richard

thanks a lot for your every reply. In my university we use phoenics version 2007 I have to ask computer center that is it available or not.

mukut

[gallant77_cfd]

Hi Mukut,

(source of u1 at bdfc is f(e) with fixv)
(source of v1 at bdfc is f(e) with fixv)
(source of w1 at bdfc is f(e) with fixv)

It should be corrected as below.

(source of u1 at bdfc is f(e) with fixflu)
(source of v1 at bdfc is f(e) with fixflu)
(source of w1 at bdfc is f(e) with fixflu)

[gallant77_cfd]

Hi Mukut,

There are many information regarding PHOENICS in POLIS (PHOENICS On-Line Information System). You can launch it by
Starts in Windows--->Programs--->Phoenics 2007----> Polis

Regards
Richard

[mukut]

Thanks for your every advices. I always read POLIS from http://www.cham.co.uk/phoenics/d_polis/polis.htm because PHOENICS is not installed directly in my PC, I use ASTEC-X to use Phoenics from my University server PC.

I have made a q1 file,

1. use EPOT (http://www.cham.co.uk/phoenics/d_pol...e.htm#epot)for electric potential and also use a simple boundary condition sin(XG)*Sin(1) for inlet and Sin(ZG)*Sin(1) for outer boundary.

2. Upper part of solution domain contains air with permittivity 1 and bottom part as a dielectric by using PATCH command and permittivity is 2.3 for kapton. The domain looks like as follows-

To activate CVD, I followed the instruction as given here(http://www.cham.co.uk/phoenics/d_pol...oen/runcvd.htm) like: The CVD options are activated by setting NAMGRD=CVD; this line should therefore always be included.

but running earth, shows error, from result file:
Special GROUND CVD is in use
Unable to access file SPECIDAT: please
check that it is in the local directory

why SPECIDAT is unable? I can't understand it..............

waiting for your reply


according to

[mukut]

Dear rechard!

I need to use this eqn. because it has to be set on upper electrode to calculate electric potential. how can i define? omega is 2*pi*f and f can be taken from period of time. but how is about t? I mean PATCH(EPOT, CELL, ..........................1, lstep) ???

Another question, how can I make such domain (comments#7) that means bottom electrode is inserted to dielectric material? Is it possible to make in phoenics or any other geometry generator is needed??

[previous time i didn't get strong support like you, may be I have already made you bored , sorry for that]

[mukut]

DEAR Richard,

I have asked computer center of my university he said that Phoenices CVD is not available in my university

[gallant77_cfd]

Originally Posted by mukut

Dear rechard!

I need to use this eqn. because it has to be set on upper electrode to calculate electric potential. how can i define? omega is 2*pi*f and f can be taken from period of time. but how is about t? I mean PATCH(EPOT, CELL, ..........................1, lstep) ???

Another question, how can I make such domain (comments#7) that means bottom electrode is inserted to dielectric material? Is it possible to make in phoenics or any other geometry generator is needed??

[previous time i didn't get strong support like you, may be I have already made you bored , sorry for that]

Hello Mukut,

You can directly put the electrode objects in the domain and then set the object as the user defined and then use the patch name as elect and elect2
patch(elect2, cell, ..................,1, lstep)
coval(elect2,epot,fixval,0)

patch(elect, cell,..............,1,lstep)
real(epmax,omig)
epmax=...
omig=...
(source of epot at elect is epmax*sin(6.283184*omig*tim) with fixval)

Rigards
Richard

[mukut]

Dear Richard,

Thanks and grateful to you for your every advice. Previous reply I made a mistake as I defined PATCH as EPOT it was a type mistake.

I have tried with the following..

PATCH(UELEC,CELL,.............1,LSTEP)
(SOURCE of EPOT at UELEC is 4*SIN(31415.9*TIM))
PATCH(BELEC,CELL,..........,1,LSTEP)
(SOURCE of EPOT at BELEC is 0)

for both electrode I have used INFORM, but when I use patch for bottom electrode which is inside of DIELECTRIC show ERROR in RESULT file: Unknown l0f argument

now trying with your advises...let's see

[mukut]

Dear Richard,

Now the error has gone. But EPOT gives the value of order E-04, hope it will be solved very soon. One thing, when I run virtual reality viewer the VECTOR button shows only the velocity vector if I click on C then EPOT to view the contour and click on VECTOR button to check the EPOT vector... contour is ok for EPOT but VECTOR shows for VELOCITY. how can I solve it?

[IMG]file:///C:/DOCUME%7E1/mukut/LOCALS%7E1/Temp/moz-screenshot.png[/IMG] check this pic. same vector is showed for velocity but in also same for EPOT. The contour is for EPOT.

[mukut]

Originally Posted by gallant77_cfd

Hello Mukut,

You can directly put the electrode objects in the domain and then set the object as the user defined and then use the patch name as elect and elect2
patch(elect2, cell, ..................,1, lstep)
coval(elect2,epot,fixval,0)

patch(elect, cell,..............,1,lstep)
real(epmax,omig)
epmax=...
omig=...
(source of epot at elect is epmax*sin(6.283184*omig*tim) with fixval)

Rigards
Richard

Dear Richard,

Sorry I was busy with experiments and making a manuscript. I have tried the simulation with above mention statement. but EPOT didn't give any result at electrode :-( still trying. If you have any more suggestion, let me know plz :-(

[mukut]

Dear Richard, where are you? I have resolve some problem. Now problem is when I increase the NX then simulation result totally peculiar....

[gallant77_cfd]

Hello Mukut,
Could you please e-mail me the q1 file ?
Also regarding the electrical potential, have you set the electrical conductivity ? Prndtl(epot)=....
Where do you set the permittivity ? I have to check this problem.
Regards
Richard