whats the cause of error?
 

i have written three pressure BC.and then tried to do by groovyBC.although it seems equivalent to others it don't work.
if this problem resolve i think the trouble is removed.
fixedValue p:OK
totalPressure:OK
but groovyBC:
results in:
why?
thanks for quick helps.

the whole p is:
the problem is in p(other variables are ok as i tested)
I have to write BC in groovyBC form because of more complicated main case I have to solve.
thanks very much.please answer rapidly.;)

There are several issues:

• Divide by Zero Error I am taking a guess that there is a divide by zero in there
  Code:

  ---

  Floating point exception

  ---

  If I were to start to track that one down, I would look where a divide by zero might be. Looking at what you have provided...I would say its near
  
  Code:

  ---

  valueExpression "1023382.5/pow(1+(1.41)*magSqr(U)/(2*1.4*287.14*T),3.5)";

  ---

  which is equivalent to
  
  
  
  I see a T in the denominator, and if there is a zero there....one will have a divide by zero issue....this could be the problem
  
• OpenFOAM Protip
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Your BC may be giving the error when a boundary condition is corrected and has a T == zero for some reason. Honestly, without more information this is the best i can do with solving your issue...but its an educated guess at this point.

#OFProtip

thanks.T isn't zero and also its same for all three tests.but only in groovy it occurs.

did you try another time integration scheme? I see a backwardDdtScheme in your error message and there may be something happening there. Also, just to prove that its not the T in the denominator, change your value expression to

and give it a try.

i changed time scheme to Euler and changed T but error persists.initial U is zero and i changed it but the error didn't change
these are variable BC's:
p:
U:
T:
fvSolution is:
fvScheme:
and at last controlDict:

thanks for your effort to help dear Daniel.
It was because of new groovyBC.I changed to old version and it answer now.

OK, it is indeed your BC setup. I don't have the time to set this up for you, but i have some suggestions.

• go and look through the groovyBC examples, they will cover what you want. If you dont have them, google for them...they are out there :D
• Start with a simpler groovyBC that will be easier to debug.

Good luck

EDIT: read your new post that just mystically appeared....glad you figured it out :)

a question occur to me that I'm curious about.
when I set BC for U to zeroGradient or:
it answers without any error
but when I set it to:
it falls to an error on T(energy equation probably) as so:
I thought that internalField(U) or vector(internalField(U).x,0,0) do the same way as zeroGradient(or in groovyBC gradientExpression"0" does).
why?

Hi Ehsan,

Did you find any clue for above warning to fix?

Regards,
CFDUser_

Hi, yes I did it ! if I remember truely, it was because of the BC. when we use zeroGradient BC it solves the equations implicitly but when use internalField the equations are solved explicitly and may be unstable although in both cases the values on the boundary and internal value is the same but in zeroGradient case we say to OpenFOAM that solve these equations so that the values on the boundary be at last equal as the value on neighbor cells but in internalField case we say put the value on the neighbor cells on the boundaries now and then solve the equations!
besides that, the velocity on outward flow should be read from inside implicitly and only pressure should be set there as a known value otherwise error will arise due to instability.
I hope these explanations be what you asked about.

Wow, This is more than expected. Thanks a lot Ehsan. :)

Regards,
CFDUser_

Hi,
I also have this problem. But I don't know how to fix it.

--> FOAM Warning :
From function Foam::scalar Foam::janafThermo<EquationOfState>::limit(Foam::sc alar) const [with EquationOfState = Foam::perfectGas<Foam::specie>; Foam::scalar = double]
in file /home/pawan/OpenFOAM/OpenFOAM-v1812/src/thermophysicalModels/specie/lnInclude/janafThermoI.H at line 117
attempt to use janafThermo<EquationOfState> out of temperature range 200 -> 5000; T = -388.868
--> FOAM Warning :
From function Foam::scalar Foam::janafThermo<EquationOfState>::limit(Foam::sc alar) const [with EquationOfState = Foam::perfectGas<Foam::specie>; Foam::scalar = double]
in file /home/pawan/OpenFOAM/OpenFOAM-v1812/src/thermophysicalModels/specie/lnInclude/janafThermoI.H at line 117
attempt to use janafThermo<EquationOfState> out of temperature range 200 -> 5000; T = -111.631
min/max(T) = 200, 1742.55

Any suggestion?

I read that the problem could be about different values in BC in the Internal Field and in the neighbor cells, but i did not understand exactly what it means!

Hi, I have a same problem when using reactingFoamLTS

Do you have any idea about this issue?