[odellar]

Hi,

I want to implement a time varying boundary condition which simply varies the velocity magnitude as a function of some measurement - i.e. closed-loop control.

So whilst running a solver (PIMPLE in my case) I want a probe to save a value (for example a pressure measurement) at each time step, then the ability to perform some mathematical operation on this value, determining the velocity magnitude of my particular boundary for the next time step, then to set this velocity for the next time step.

Can anyone help me out with this?

Thanks a lot, Olie

[olivierG]

hello,
GroovyBC can do this, check the wiki.

Regards,
Olivier

[odellar]

Thanks Olivier, this looks promising.

Regards,
Olie

Originally Posted by olivierG

hello,
GroovyBC can do this, check the wiki.

Regards,
Olivier

[odellar]

Hi,

I've now got (I think) swak4FOAM properly installed and wish to have a go with this.

If I have a boundary (let's call it actuator) whose velocity I want to set using groovyBC based on an expression involving the pressure recorded by a probe (let's call it probe1), how can I do this?

My thinking is in the file case/0/U change the actuator boundary field to something like:

actuator
    {
    type                     groovyBC;
    valueExpression        "0.5*(probeReading)"; // Some function of the probe recording
    variables                "probeReading *** NOT SURE HOW TO DO THIS? ***
    value                     uniform (0 0 0);
    }

and it needs to use the current time step's probeReading value such that it updates the boundary condition based on the mathematical function of this value for the next timestep.

Can anyone help me with this?

Thanks a lot in advance,
Olie

[haolee0928]

Originally Posted by odellar

Hi,

I want to implement a time varying boundary condition which simply varies the velocity magnitude as a function of some measurement - i.e. closed-loop control.

So whilst running a solver (PIMPLE in my case) I want a probe to save a value (for example a pressure measurement) at each time step, then the ability to perform some mathematical operation on this value, determining the velocity magnitude of my particular boundary for the next time step, then to set this velocity for the next time step.

Can anyone help me out with this?

Thanks a lot, Olie

Hi, have you finishe it? I am doing the same simulations.