Hi!

I am investigating the drag on an evaporating sphere (as if it where an evaporating droplet) using the FLUINJ subroutine to simulate the mass injection from the sphere.

My problem is that the user subroutine ,FLUINJ, although it is being read in the analysis, nothing seems to happen. I have tried changing the FLUXI,UI,VI,WI,etc. variables to no avail. Does anyone know if the FLUINJ subroutine has an error and does not work properly? Any suggestions would really be helpful.

Thank you for your assistance.

The FLUINJ subroutine has no error and worked well in my case.

cell type of part with mass change = 10

= > IF(ICTID.EQ.10) THEN

FLUXI= XXXX

ENDIF

As with all user subroutines, there's more to activating and using FLUINJ than just wishing it would work. You need to activate it in PROSTAR, write a meaningful fluinj.f, put it in the ufile directory and compile it into the STAR executable. Usually it is the first or the last of these which you forget to do when you find nothing is happening.

As I mentioned in my message before, the FLUINJ subroutine has been activated via PROSTAR and through the STAR executable!

It seems that I am missing out something else. Any other suggestions would be great!

Thanks!

Did you see some warnings at the start of STAR? I think that you might set the wrong ICTID in your subroutine.

The best way to check is:

In prostar STARGUIde, =>Analysis Control => Output Controls => Monitor Numeric Behavior =>

select Print Iteration Residuals and Conservation Checks, then when you run STAR, you can check the .info file and for example, MATERIALWISE MASS BALANCE, if you have fluid injection, you should have non-zero value for term FLINJ

You can try whether your subroutine is considered in solution by adding some code into the subroutine. That code will print information given in subroutine to display. If the subroutine is correctly linked and used during a solution, the text "my subroutine is being used" and "expression IF passed" will be printed. If these texts will not be printed, the problem might be in the initialisation process at PROSTAR.

For example:

C

if (ip.eq.1) then

write(*,*) "my subroutine is being used"

endif

if(ictid.eq.something) then

if (ip.eq.1) then

write(*,*) "expression IF passed"

endif

your source FLUXI = ...

endif

RETURN

END

C

I normally do this sort of thing by default in my STAR user routines:

LOGICAL INIT DATA INIT /.TRUE./

IF (INIT) THEN WRITE(*,*) 'NAME OF USER ROUTINE' INIT = .FALSE. ENDIF

Otherwise you can never really be sure if your routine ever gets called.

Stupid bloody formatting buggered my previous message good and proper!