27.11.1 Manipulating Adaption Registers

You can manipulate, delete, and display adaption registers by marking cells for adaption. Since these registers are used to adapt the mesh, the ability to manipulate them provides additional control over the adaption process.

Management of adaption registers is performed in the Manage Adaption Registers dialog box (Figure  27.11.1). You can also open this dialog box by clicking on the Manage... button in any of the adaption dialog boxes.

Adapt $\rightarrow$ Manage...

Figure 27.11.1: The Manage Adaption Registers Dialog Box

You can modify and manipulate adaption registers by:

• changing the register types

• combining the registers

• deleting the registers

Changing Register Types

If the adaption register is converted to a mask, the cells marked for refinement are ACTIVE, and all other cells are INACTIVE (i.e., the cells marked for coarsening are ignored). Generally, the adaption registers converted to masks are those that are generated by adaption functions that mark cells exclusively for refinement, such as region or isovalue adaption functions. The other major difference between adaption and mask registers is the manner in which they are combined.

To change the type of one or more registers from adaption to mask, or vice versa, do the following:

1.   Choose the register(s) in the Registers list.

2.   Click on the Change Type button under Register Actions.

The new type of the register (if multiple registers are selected, the most recently selected or deselected register) will be shown as the Type under Register Info. Select each register individually to see what its current type is.

Combining Registers

After the individual adaption registers have been created and appropriately modified, they are combined to create hybrid adaption functions.

1.   Any number of registers can be combined in the following manner:

• All adaption registers are combined into a new adaption register.

• All mask registers are combined into a new mask register.

• The new adaption and mask registers are combined.

2.   Any number of adaption registers can be combined in the following manner:

• If the cell is marked for refinement in any of the registers, mark the cell for refinement in the new register (bitwise OR).

• If the cell is marked for coarsening in all of the registers, mark the cell for coarsening in the new register (bitwise AND).

3.   The mask registers are combined in a manner similar to the refinement marks. If any cell is marked ACTIVE, the cell in the new register is marked ACTIVE (bitwise OR).

4.   Finally, in the combination of an adaption and mask register, only cells that are marked in the mask register can have an adaption mark in the combined register (bitwise AND).

For example, creating an adaption function based on pressure gradient may generate cells marked for refinement and coarsening throughout the entire solution domain. If this register is then combined with a mask register created from cells marked inside a sphere, only the cells inside the sphere will be marked for refinement or coarsening in the new register.

Note:   The effect of masks depends on the order in which they are applied.

For example, consider two adjacent, circular masks. Applying one mask to the adaption register and then applying the other mask to the result of the first combination would give a much different result than applying the combination of the two masks to the initial adaption register. The second combination results in a greater possible number of marked cells.

To combine two or more registers, do the following:

1.   Choose the registers in the Registers list.

2.   Click on the Combine button under Register Actions.

The selected registers will remain intact, and the register(s) resulting from the combination will be added to the Registers list. In some instances, three new registers may be created:

• a combination of the adaption registers

• a combination of the mask registers

• a combination of the two combined registers

For more information about combining registers, see this section in the separate Theory Guide.

Deleting Registers

The primary reason for deleting registers is to discard unwanted adaption registers. This will reduce confusion and the possibility of generating undesired results by selecting these discarded registers. In addition, only 32 adaption registers can exist at one time. Therefore discard unwanted registers to make room for new ones. You can delete any number of adaption registers.

To permanently remove one or more registers, do the following:

1.   Choose the register(s) in the Registers list.

2.   Click on the Delete button under Register Actions.