[chirag1993]

Hi,
I'm doing combustion of solid fuel particles bed. I have a cylinder pellet with atm temperature and at left plane temperature is constant as my boundary condition. In energy source option I gave volumetric heat source with field function($Temperature>= 933 ? 968500000000:0).So it will release the energy when temperature exceeds ignition temperature(933K).
But in reality after exceeding 933K at point, upto burning time(0.00008 s) heat is released, so how can I save the time(t_0) at every location so that I can use this condition in my field function t<t_0+0.00008 to release the heat?
Thanks in advance for your precious time

[fluid23]

I am confused. Are you asking how to use the time value from the previous time step or from the first time step?

[chirag1993]

First time step at every location.
Let me clear perfectly. Each point will release heat upto deltaT time after exceeding Ignition temperature(933K). I want to know the time (from beginning (0 sec)) at each cell when my particle reach the temperature 933K ,so that I can give the condition like from now upto deltaT time heat will be released.

If I can do this without knowing the time then it is also fine, means at one cell when I reach the temperature it will start releasing heat and stop it after deltaT(0.008 sec).

If you have solution or any new idea please share with me?
(Just for information -Here size of each particle will become mesh cell size, it means if i decrease the mesh cell size particles will become fine.)

[chirag1993]

It's weird that no one knows or limitation of star CCM+?
Help me if you know.

[mirSTS74]

If I understand correctly, you want to know which cells hit a specific temperature and the time they achieve that.

I think using threshold(under derived parts) or cell sets may help you.

[chirag1993]

these three things I want to do in star ccm.
1) increment {Temperature>933 ? tb+0.00067:tb}
2) tb {Temperature>933 ? increment:0}
3) Heatgeneration {Temperature>933 && increment<0.0067 ? 90000:0}

These can't be done by using field function because its cyclic .
I created macro for these field functions and trying to change it but I got many errors like can't find symbol, so I'm just attaching generated macro file with little bit changes, so you can guide me.

UserFieldFunction userFieldFunction_4 =
simulation_0.getFieldFunctionManager().createField Function();
userFieldFunction_4.getTypeOption().setSelected(Fi eldFunctionTypeOption.SCALAR);
userFieldFunction_4.setFunctionName("tb");
userFieldFunction_4.setDefinition("0");

UserFieldFunction userFieldFunction_5 =
simulation_0.getFieldFunctionManager().createField Function();
userFieldFunction_5.getTypeOption().setSelected(Fi eldFunctionTypeOption.SCALAR);
userFieldFunction_5.setFunctionName("incre");

UserFieldFunction userFieldFunction_6 =
simulation_0.getFieldFunctionManager().createField Function();
userFieldFunction_6.getTypeOption().setSelected(Fi eldFunctionTypeOption.SCALAR);
userFieldFunction_6.setFunctionName("main");

Units units_0 =
simulation_0.getUnitsManager().getPreferredUnits(n ew IntVector(new int[] {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}));

Units units_1 =
simulation_0.getUnitsManager().getPreferredUnits(n ew IntVector(new int[] {0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}));

PhysicalTimeStoppingCriterion physicalTimeStoppingCriterion_0 =
((PhysicalTimeStoppingCriterion) simulation_0.getSolverStoppingCriterionManager().g etSolverStoppingCriterion("Maximum Physical Time"));
physicalTimeStoppingCriterion_0.getMaximumTime().s etValue(0.1);


do {

if(simulation_0.getSolution().getPhysicalTime() > 0){

userFieldFunction_5.setDefinition("($Iteration>0)? ($Temperature > 933) ? ${tb}+0.000668:${tb}:0");
userFieldFunction_4.setDefinition("($Iteration>0)? ($Temperature > 933) ? ${incre}:0:0");
userFieldFunction_6.setDefinition("($Iteration>0)? ($Temperature > 933 && ${incre} < 0.0067) ? 968500000000:0:0");

Region region_0 =
simulation_0.getRegionManager().getRegion("half_cy linder.prt");

VolumetricHeatSourceProfile volumetricHeatSourceProfile_0 =
region_0.getValues().get(VolumetricHeatSourceProfi le.class);

volumetricHeatSourceProfile_0.getMethod(FunctionSc alarProfileMethod.class).setFieldFunction(userFiel dFunction_6);


}

simulation_0.getSimulationIterator().step(10);


} while (!physicalTimeStoppingCriterion_0.getIsSatisfied() );

}
}

By using these macro I'm getting cyclic error.
Help me out.
I'm thinking may be I need to change only three equations in do loops in some how.
Answer for earlier post-Threshold and cell set don't work in this case.

[chirag1993]

Can anyone know which function is used to store the values of field function in Macro(java script), means to store the scalar value we use setValue but don't know for a field function. May be problem can be solved I'm not sure. I will tell you later after checking it.

[mirSTS74]

Have you tried contacting Cd-Adapco about it?

[chirag1993]

No, Within few days I will. And tell you answer if I get.