The parameters in this rollout control the size and resolution of the grid.



Cell size (MXS: cellsz) - the size of singe cell.

X,Y,Z size (MXS: xc, yc, zc ) - the grid size in cells. The real size is reported left of the cell size, just for information.


Increase/Decrease resolution (MXS: ) - changes the resolution of the grid while maintaining its size.


Boundary Condition


X,Y,Z (MXS: x_bound, y_bound, z_bound ) - select between different boundary conditions for the simulation grid.


Open - the simulation behaves as if there is infinite fluid beyond the boundary.

Jammed(-) - the simulation behaves as if there is a solid boundary in the negative direction.

Jammed(+) - the simulation behaves as if there is a solid boundary in the positive direction.

Jammed Both - the simulation behaves as if there is a solid boundary in both directions.

Wrap - the left and right boundaries are connected (toroidal topology).

Adaptive Grid (MXS: adaptive) - enables the adaptive grid mode and determines which channel to use (See Threshold parameter).

Threshold (MXS: grid_treshold) - in adaptive mode the change of grid's size is performed when the content of a cell near the borders crosses this value.


Extra Margin (MXS: adapt_margin) - the width of the belt of cells kept between the active zone and the end of the grid.


Limited by (MXS: limitby) - determines whether the grid's expansion is to be limited. If that is the case, it also determines the units in which the Limited to value is expressed in.


None - no limitation.

Memory - limit by the total consumed memory. The limit is specified in percentages.

Cells - limit by the cells count. The limit is specified in millions of cells.


Limited to (MXS: limit) - the limit of grid expansion (if active). The meaning of this value is given by the Limited by parameter.


Preallocate memory (MXS: prealloc_mem) - when the grid size is changed, a new grid is allocated and the old content is transferred into the new space. However, during this process, both grids, the new and the old one exist simultaneously and the RAM usage is doubled. This is a big problem because the doubled consumption limits the memory usage to 1/2 of those without adaptive grid. This option allocates all the possible RAM for a single huge grid, and simulates only in a part of it, allowing resize without doubling the memory usage.


Disabled - no preallocation is used.

When Adaptive - only when adaptive grid is enabled.

Always - even with no adaptive grid preallocation is used, this may be useful if you change the grid size by hand.


No below initial grid (MXS: nbigrid) - when checked the initial grid is always inside of the adaptive grid.