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A way to update groovyBC variables during the solution

hi
I was searching for the cause of not changing the results when I change groovyBC variables for all two days and nights!
I had run till a important time that a change in BC occurs but it need to change a variable for better simulation.i was changing related variables but nothing seem to change! I simplified it and deleted everything but surprisingly it was not fixed.
at last i found that it should be run from starting so that groovyBC can update its variables.
then i search for a way to update groovyBC variables and expressions after stopping the solution during a run.is such thing available?or i have to start from zero folder again and again?
thanks.

is any help available?is it possible by any of groovyBC or pyFOAM utilities?does such thing exist?

Quote:

Originally Posted by immortality (Post 404636)

I assume you're talking about the variables of groovyBC? These are evaluated at every timstep anew. For additional tests you can add these two settings to the groovyBC:

Code:

debugCommonDriver true;

debug true;

The first setting produces loads of output to the terminal. The second one should write the values of the variables into the outputfiles (but I haven't used that in a long time)

I forgot to put ; after valueExpression so far.but no error has shown.what may be the cause?
I add these expressions in all groovyBC boundary conditions and get a run?
thanks.

Quote:

Originally Posted by immortality (Post 405366)

I forgot to put ; after valueExpression so far.but no error has shown.what may be the cause?
I add these expressions in all groovyBC boundary conditions and get a run?
thanks.

OpenFOAM doesn't complain about the missing ; as it found the expected string. The next parameters until another ; are ignored because OF believes that they are part of valueExpression

thanks.
Should i add two expressions you told me to every groovyBC conditions?
I have the problem yet.i have run untill an important time(that moving shock faces to wall and reflects) before it happens i want to change a variable relating to time of opening of the wall(to find a proper value) but no change occurs unless i delete all time step folders and start from begining.is it a true situaion?
You mean groovyBC should read 0 folder in each time step again?
Thank you.

Quote:

Originally Posted by immortality (Post 405472)

thanks.
Should i add two expressions you told me to every groovyBC conditions?

No! Only the one you have problems with. They produce a lot of output and are only necessary if you can't spot the problem by looking at it

Quote:

Originally Posted by immortality (Post 405472)

I have the problem yet.i have run untill an important time(that moving shock faces to wall and reflects) before it happens i want to change a variable relating to time of opening of the wall(to find a proper value) but no change occurs unless i delete all time step folders and start from begining.is it a true situaion?
You mean groovyBC should read 0 folder in each time step again?
Thank you.

OpenFOAM only reads the fields once (according to startFrom/startTime) and then works with whatever is in memory. If you restart from t=100 then changes you made in t=0 are irrelevant (if that is what you mean)

If you have problems with implementing dynamic boundary conditions first test them on a tiny "toy-case" that is similar to the real case

thanks.yes I mean that you say.then changing groovyBC variables has no effect on the problem when we are at 100th time step.does it?
I have examined groovyBC by replayTransientBC.the trend seems ok.
but something takes place that i think must not be related to groovyBC,the BC is updated after 2 or 3 time steps.is it because time steps are lower than reaching the new condition(wall) to next cell?then i should decrease the size of cells more,shouldn't i?

1)I found this expression when I used replayTransientBC in my groovyBC's:

Code:

evaluateDuringConstruction 0;

can it be the answer of problem if i change it to 1?(then it updates during run and reads from 0 folder that groovyBC's have specified?)

2)after applying replayTransientBC my p in 0 folder look like this.is it ok?or i should set values for refValue and refGradient and valueFraction?

Code:

right

    {

        type            groovyBC;

        refValue        uniform 0;

        refGradient     uniform 0;

        valueFraction   uniform 1;

        value           uniform 1.02338e+06;

        valueExpression "p0_2*pow(par2,-3.5)";

        gradientExpression "0";

        fractionExpression "(t1<time()&&time()<t1+c1)||(t2<time()&&time()<t2+c1)||(t3<time()&&time()<t3+c1)||(t4<time()&&time()<t4+c1)||(t5<time()&&time()<t5+c1)||(t6<time()&&time()<t6+c1)||(t7<time()&&time()<t7+c1)||(t8<time()&&time()<t8+c1)||(t9<time()&&time()<t9+c1)||(t10<time()&&time()<t10+c1)||(t11<time()&&time()<t11+c1)?1:0";

        evaluateDuringConstruction 0;

        variables       

43

(

"ymax=max(pos().y);"

"ymin=min(pos().y);"

"r=0.02325;"

"rpm=32151;"

"omega=rpm*pi/30;"

"v_r=r*omega;"

"w_cell=.004;"

"n=1;"

"w_w0=n*w_cell;"

"w_w1=(115.63-46)*r*pi/180;"

"w_w2=(180-159.28)*r*pi/180;"

"w_w3=(21.6-0)*r*pi/180;"

"w_w4=(83-61.6)*r*pi/180;"

"w_w5=(180-128)*r*pi/180;"

"w_p1=(160.28-116.63)*r*pi/180;"

"w_p2=(71.1-21.6)*r*pi/180;"

"w_p3=(46-0)*r*pi/180;"

"w_p4=(129-84)*r*pi/180;"

"c1=w_p2/v_r;"

"c2=(w_p2+w_w4)/v_r;"

"c3=(w_p2+w_w4+w_p4)/v_r;"

"c4=(w_p2+w_w4+w_p4+w_w5+w_w3)/v_r;"

"t1=(w_w0+w_w3-pos().y)/v_r;"

"t2=t1+c4;"

"t3=t1+2*c4;"

"t4=t1+3*c4;"

"t5=t1+4*c4;"

"t6=t1+5*c4;"

"t7=t1+6*c4;"

"t8=t1+7*c4;"

"t9=t1+8*c4;"

"t10=t1+9*c4;"

"t11=t1+10*c4;"

"p0_1=303975;"

"T0_1=440;"

"p0_3=932190;"

"T0_3=1248;"

"p0_2=1023382.5;"

"T0_4=973;"

"gamma=1.4;"

"R=287.14;"

"par1=1-(gamma-1)*magSqr(internalField(U))/(2*gamma*R*T0_1);"

"par2=1+(gamma-1)/2*magSqr(internalField(U))/(gamma*R*internalField(T));"

)

;

        timelines       (

);

        lookuptables    (

);

    }

3)what does valueFraction means when i have set fractionExpession?whats its usage?
thanks.

any answer is thanked and appreciated.