Control Volume¶

Introduction¶

A control volume is an analysis tool that computes local particle and fluid properties within user-defined regions. The control volume can be specified as either a cylinder or a cuboid. For each region, the tool reports descriptive statistics with the control volume and fluid volume fluxes across all faces. The tool also reports particle residence time metrics, including mean and maximum residence times.

Property Grid¶

`General`¶

Shape

The shape of the control volume zone can be defined using either a box or a cylinder. Both geometry are grid-aligned.

Box

Box control volumes are three-dimensional cuboids defined by a box center and box side length. Control volume boxes cannot be rotated. As such, the sides of the box are always aligned with the basis X, Y, and Z unit vectors defining the main lattice.

Center: m | The center of the shape.
Box Length X: m | X-side length of the control volume box.
Box Length Y: m | Y-side length of the control volume box.
Box Length Z: m | Z-side length of the control volume box.

Cylinder

Cylinder control volumes are three-dimensional cylinders defined by a cylinder center, cylinder radius, and cylinder length. Control volume cylinders can be rotated. As such, the cylinder axis will be aligned with the basis X, Y, and Z unit vectors defining the main lattice.

Center: m | The center of the shape.
Cylinder Diameter: m | Cylinder diameter.
Cylinder Length: m | Cylinder length.
Cylinder Axis Vector: Vector that orients the cylinder.

`Display Attributes`¶

Visible

This controls whether the object is displayed in the 3D viewing panel.

Hidden

The object is not displayed in the 3D view.

Shown

The object is displayed in the 3D view.

Mode

This controls how the object is rendered.

Wire

This renders the object as a wireframe.

Color: This sets the color of the wireframe.
Width: This adjusts the line width used to render the wireframe.

Shaded

This renders the object as a shaded surface.

Material: This sets the surface material. Available options are Aluminum, Steel, Chrome, Plastic, and Glass.
Color: This sets the surface color.
Opacity: When glass is selected, this sets surface opacity.

Control Volume Output Data¶

The time-evolving data from control volume will be recorded in tab-separated ASCII .txt files. Each control volume will have a unique output file with a file name linked to its dynamic name.

The data printed to the ASCII data files will be the combined selections of the Probes/Planes Output Controls and Volume Output Controls. A preview of the data printed to each control volume output file is listed in the Statistics Output Data preview panel. The ASCII .txt are appended with updated data at the Statistics Output Write Interval.

In addition to the ASCII files, the current residence time of each particle within each control volume is printed as supplementary data to each particle .vtp file. This particle data can be used for rendering, visualization, and analysis within M-Star Post. These visualization files are printed at both the Plane/Probe Output Write Interval and the Volume Output Write Interval, allowing for concurrent animation of local residence times in both 2D and 3D renderings.

For more information about the .vtp file structure, see the Visualization Toolkit.

Control Volume Toolbar¶

Context-Specific Toolbar Forms	Description
Move	The Move form enables three-dimensional rigid body transform of object through free drag or point-to-point snapping.
Rotate	The Rotate form enables three-dimensional rotation of geometry.
Scale	The Scale form enables volumetric scaling of a geometry about a set anchor point.
Help	The Help command launches the M-Star reference documentation in your web browser.

For a full description of each selection on the Context-Specific Toolbar, see Toolbar Selections.