[mahdi-united]

Originally Posted by vinerm

T_derivatives function is declared in pbns/sg.h, however, I do not think that it is relevant for you. You need to fetch gradients of mass fractions of species. That is accessible via C_YI_G or as stated earlier, using SV_Y_G, 0.

What error do you get if you use either C_YI_G or SV_Y_G? I would recommend the former since that is an easy wrapper for users.

this is modification code


DEFINE_ADJUST(gradient, domain)
{
Thread *t;
Thread **pt;
cell_t c;
Domain *pDomain = DOMAIN_SUB_DOMAIN(domain,P_PHASE);
real voidx, voidy, voidz=0.0;
{
Alloc_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_N ULL);
Scalar_Reconstruction(pDomain, SV_VOF,-1,SV_VOF_RG,NULL);
Scalar_Derivatives(pDomain,SV_VOF,-1,SV_VOF_G,SV_VOF_RG,Vof_Deriv_Accumulate);
}
{
Alloc_Storage_Vars(domain, SV_Y_RG, SV_Y_G, SV_NULL);
//Y_derivatives(domain);
Free_Storage_Vars(domain, SV_Y_RG, SV_NULL);
}
mp_thread_loop_c (t,domain,pt)
if (FLUID_THREAD_P(t))
{
Thread *tp = pt[P_PHASE];
begin_c_loop (c,t)
{
// (C_VOF_G(c,tp)[0]*C_T_G(c,t)[0]+C_VOF_G(c,tp)[1]*C_T_G(c,t)[1]+C_VOF_G(c,tp)[2]*C_T_G(c,t)[2]);
C_UDMI(c,t,0) = (C_VOF_G(c,tp)[0]*C_YI_G(c,tp,0)[0] + C_VOF_G(c,tp)[1]*C_YI_G(c,tp,0)[1] + C_VOF_G(c,tp)[2]*C_YI_G(c,tp,0)[2]);
}
end_c_loop (c,t)
}
Free_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_NU LL);
Free_Storage_Vars(domain, SV_Y_G, SV_NULL);
//Message("C_UDMI(cell,mix_air,0) = %g\n",C_UDMI(c,t,0));
}



without error and successful initializing but
when i running, appear this message 'the f1 process could not be started' and automatically FLUENT closed.

[mahdi-united]

Originally Posted by vinerm

T_derivatives function is declared in pbns/sg.h, however, I do not think that it is relevant for you. You need to fetch gradients of mass fractions of species. That is accessible via C_YI_G or as stated earlier, using SV_Y_G, 0.

What error do you get if you use either C_YI_G or SV_Y_G? I would recommend the former since that is an easy wrapper for users.

this is modified code


DEFINE_ADJUST(gradient, domain)
{
Thread *t;
Thread **pt;
cell_t c;
Domain *pDomain = DOMAIN_SUB_DOMAIN(domain,P_PHASE);
real voidx, voidy, voidz=0.0;
{
Alloc_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_N ULL);
Scalar_Reconstruction(pDomain, SV_VOF,-1,SV_VOF_RG,NULL);
Scalar_Derivatives(pDomain,SV_VOF,-1,SV_VOF_G,SV_VOF_RG,Vof_Deriv_Accumulate);
}
{
Alloc_Storage_Vars(domain, SV_Y_RG, SV_Y_G, SV_NULL);
//Y_derivatives(domain);
Free_Storage_Vars(domain, SV_Y_RG, SV_NULL);
}
mp_thread_loop_c (t,domain,pt)
if (FLUID_THREAD_P(t))
{
Thread *tp = pt[P_PHASE];
begin_c_loop (c,t)
{
// (C_VOF_G(c,tp)[0]*C_T_G(c,t)[0]+C_VOF_G(c,tp)[1]*C_T_G(c,t)[1]+C_VOF_G(c,tp)[2]*C_T_G(c,t)[2]);
C_UDMI(c,t,0) = (C_VOF_G(c,tp)[0]*C_YI_G(c,tp,0)[0] + C_VOF_G(c,tp)[1]*C_YI_G(c,tp,0)[1] + C_VOF_G(c,tp)[2]*C_YI_G(c,tp,0)[2]);
}
end_c_loop (c,t)
}
Free_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_NU LL);
Free_Storage_Vars(domain, SV_Y_G, SV_NULL);
//Message("C_UDMI(cell,mix_air,0) = %g\n",C_UDMI(c,t,0));
}


without error and successful initializing
but when i running appear this message
'the f1 process could not be started ' and automatically fluent closed

[mahdi-united]

Originally Posted by vinerm

T_derivatives function is declared in pbns/sg.h, however, I do not think that it is relevant for you. You need to fetch gradients of mass fractions of species. That is accessible via C_YI_G or as stated earlier, using SV_Y_G, 0.

What error do you get if you use either C_YI_G or SV_Y_G? I would recommend the former since that is an easy wrapper for users.

this is modification code


DEFINE_ADJUST(gradient, domain)
{
Thread *t;
Thread **pt;
cell_t c;
Domain *pDomain = DOMAIN_SUB_DOMAIN(domain,P_PHASE);
real voidx, voidy, voidz=0.0;
{
Alloc_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_N ULL);
Scalar_Reconstruction(pDomain, SV_VOF,-1,SV_VOF_RG,NULL);
Scalar_Derivatives(pDomain,SV_VOF,-1,SV_VOF_G,SV_VOF_RG,Vof_Deriv_Accumulate);
}
{
Alloc_Storage_Vars(domain, SV_Y_RG, SV_Y_G, SV_NULL);
//Y_derivatives(domain);
Free_Storage_Vars(domain, SV_Y_RG, SV_NULL);
}
mp_thread_loop_c (t,domain,pt)
if (FLUID_THREAD_P(t))
{
Thread *tp = pt[P_PHASE];
begin_c_loop (c,t)
{
// (C_VOF_G(c,tp)[0]*C_T_G(c,t)[0]+C_VOF_G(c,tp)[1]*C_T_G(c,t)[1]+C_VOF_G(c,tp)[2]*C_T_G(c,t)[2]);
C_UDMI(c,t,0) = (C_VOF_G(c,tp)[0]*C_YI_G(c,tp,0)[0] + C_VOF_G(c,tp)[1]*C_YI_G(c,tp,0)[1] + C_VOF_G(c,tp)[2]*C_YI_G(c,tp,0)[2]);
}
end_c_loop (c,t)
}
Free_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_NU LL);
Free_Storage_Vars(domain, SV_Y_G, SV_NULL);
//Message("C_UDMI(cell,mix_air,0) = %g\n",C_UDMI(c,t,0));
}



without error and successful initializing but
when i running, appear this message 'the f1 process could not be started' and automatically FLUENT closed.

[vinerm]

Are you using pressure based solver or density based? If it is pressure based, then you need to tell Fluent to specifically save gradients using the following command

(rpsetvar 'species/save-gradients? #t)

before using the UDF.

[mahdi-united]

Originally Posted by vinerm

Are you using pressure based solver or density based? If it is pressure based, then you need to tell Fluent to specifically save gradients using the following command

(rpsetvar 'species/save-gradients? #t)

before using the UDF.

thanks for helping


what is the answer for question 'species/save-gradients?'?

[vinerm]

It's not a question, rather a boolean. And the Vale is already given in my post as #t.

[mahdi-united]

Originally Posted by vinerm

It's not a question, rather a boolean. And the Vale is already given in my post as #t.

when i write the #t for answering
appear message "invalid command"

[mahdi-united]

Originally Posted by vinerm

Are you using pressure based solver or density based? If it is pressure based, then you need to tell Fluent to specifically save gradients using the following command

(rpsetvar 'species/save-gradients? #t)

before using the UDF.

when i using this message

appear message: Error: eval: unbound variable Error Object: args

[vinerm]

Whole of this command need to be given in one go, along with the parentheses.

[mahdi-united]

Originally Posted by vinerm

Whole of this command need to be given in one go, along with the parentheses.

is this message important when udf compiling?


""INFO from activate-context: context VOF: Implicit and Steady State not yet defined.

[mahdi-united]

Originally Posted by vinerm

Whole of this command need to be given in one go, along with the parentheses.

OMG i'm very tired

this command"(rpsetvar 'species/save-gradients? #t)" is ok
but still appear the message "the f1 process could not be started" and automatically FLUENT closed.

[vinerm]

Then possibly the issue is not with UDF. Does the case run without the UDF?

And are there still comments starting with // instead of contained in /* */? If yes, then you should either remove those comments or put those in /* */.

[mahdi-united]

Originally Posted by vinerm

Then possibly the issue is not with UDF. Does the case run without the UDF?

And are there still comments starting with // instead of contained in /* */? If yes, then you should either remove those comments or put those in /* */.

dear friend thanks a lot for helping



DEFINE_ADJUST(gradient, domain)
{
Thread *t;
Thread **pt;
cell_t c;
Domain *pDomain = DOMAIN_SUB_DOMAIN(domain,P_PHASE);
real voidx, voidy, voidz=0.0;
{
Alloc_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_N ULL);
Scalar_Reconstruction(pDomain, SV_VOF,-1,SV_VOF_RG,NULL);
Scalar_Derivatives(pDomain,SV_VOF,-1,SV_VOF_G,SV_VOF_RG,Vof_Deriv_Accumulate);
}
{
Alloc_Storage_Vars(domain, SV_Y_RG, SV_Y_G, SV_NULL);
Free_Storage_Vars(domain, SV_Y_RG, SV_NULL);
}
mp_thread_loop_c (t,domain,pt)
if (FLUID_THREAD_P(t))
{
Thread *tp = pt[P_PHASE];
begin_c_loop (c,t)
{

C_UDMI(c,t,0) = (C_VOF_G(c,tp)[0]*C_YI_G(c,tp,0)[0] + C_VOF_G(c,tp)[1]*C_YI_G(c,tp,0)[1] + C_VOF_G(c,tp)[2]*C_YI_G(c,tp,0)[2]);
}
end_c_loop (c,t)
}
Free_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_NU LL);
Free_Storage_Vars(domain, SV_Y_G, SV_NULL);

}

unfortunately still there is error
i think error coming from line "T_derivatives" that should be reform to mass fraction command

[vinerm]

Well, you have nothing to lose by trying T_derivatives in your code.

[mahdi-united]

Originally Posted by vinerm

Well, you have nothing to lose by trying T_derivatives in your code.

hi

do you know meaning of "-1" in command:
Scalar_Derivatives(pDomain,SV_VOF,-1,SV_VOF_G,SV_VOF_RG,Vof_Deriv_Accumulate);

[AlexanderZ]

probably it is Index that identifies the user-defined scalar,
however, index must be > -1, so I could be wrong

[mahdi-united]

Originally Posted by AlexanderZ

probably it is Index that identifies the user-defined scalar,
however, index must be > -1, so I could be wrong

thanks for helping
how to change this section :
Alloc_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_N ULL);
Scalar_Reconstruction(pDomain, SV_VOF,-1,SV_VOF_RG,NULL);
Scalar_Derivatives(pDomain,SV_VOF,-1,SV_VOF_G,SV_VOF_RG,Vof_Deriv_Accumulate);


for accessing the mass fraction gradients?

[mahdi-united]

Originally Posted by AlexanderZ

probably it is Index that identifies the user-defined scalar,
however, index must be > -1, so I could be wrong

and another question
is there identical command "Vector_Derivatives(pDomain,SV_Y,0,SV_Y_G,0,SV_Y_R G,0,yi_derivatives)"

in udf?

[vinerm]

-1 is actually SV_NULL and is a variable attribute defined in Fluent's variable structure. Anything more than that would be a goose chase.

For mass fractions, use Y in place of VOF. Vof_Deriv_Accumulate is to be replaced with NULL.

Yes, Vector_Derivatives, Vector_Reconstructionn, as well as Vector_Gradient_Reconstruction exist. This is when user wants a gradient but not spatial.

[mahdi-united]

Originally Posted by vinerm

-1 is actually SV_NULL and is a variable attribute defined in Fluent's variable structure. Anything more than that would be a goose chase.

For mass fractions, use Y in place of VOF. Vof_Deriv_Accumulate is to be replaced with NULL.

Yes, Vector_Derivatives, Vector_Reconstructionn, as well as Vector_Gradient_Reconstruction exist. This is when user wants a gradient but not spatial.

thanks for responding
do i should write the commands :

"Alloc_Storage_Vars(pDomain,SV_VOF_RG,SV_VOF_G,SV_ N ULL);
Scalar_Reconstruction(pDomain, SV_VOF,-1,SV_VOF_RG,NULL);
Scalar_Derivatives(pDomain,SV_VOF,-1,SV_VOF_G,SV_VOF_RG,Vof_Deriv_Accumulate);"


for mass fraction gradients?(modify ocde by replacing VOF with Y and etc)