Power Regulation Infrastructure

[gsgall]

Proposed Label - Enhancement

Motivation

It is often the case that experiments will hold power deposition into the plasma constant. Currently the power deposition in an RF system primarily affected by the amplitude of the applied voltage boundary condition. In order to facilitate better comparisons with experiments there is a need to be able to regulate the power deposition in the plasma. In order to do this the average periodic power deposition in the plasma should be used. We should also give the ability to average the power deposition over multiple periods and start updating the voltage amplitude after the firs n, user defined, periods and only update the voltage BC amplitude after m ,user defined, periods so the system has some time to relax.

Design

Several Postprocessors that feed into each other can give more general functionality for other potential use cases as well enable this specific use case.

• A time integrated post processor which allows for the integration of another post processor while also multiplying that post processor value by a constant value. This is important for multiplication by the domain scaling as well as the assumed cross sectional area for 1D simulation and the assumed length/width/depth for a 2D simulation
• A periodic time integrator which inherits from the above post processor and resets this integral at the start of each period
• A multi period average. Which will allows us to average the value of a periodic integral over multiple periods
• A voltage amplitude regulator which allows us to modify the amplitude of a voltage BC starting after a user specific number of periods have occurred, and wait n periods between updating the value of the voltage boundary condition amplitude.
• Created a linear combination aux kernel to add multiple variables that have the '+' character in their name. Currently we can calculate the total power deposition in each species in the plasma with the PowerDep. The total power could be calculated with the ParsedAux, AuxKernel if their name does not contain the + or - character. But I would like to automate power regulation later with an action and have that action create Auxkernels in a naming convention that is consistent with user defined names and we may have names like Ar+_PowerDep which cannot be properly parsed by ParsedAux