# Property Editor

The Property Editor shows all the properties of a selected object and enables you to edit them.

The Property Editor can be opened and closed in the following ways:
• Clicking View > Property Editor from the menu bar
• Pressing F3
• Right-clicking on selected objects and choosing Properties/Hide Properties from the context menu
Properties that are not editable appear grayed out. Properties such as a name and color can be assigned to various objects, such as parts, or to an entire model. If multiple objects are selected, the values of properties which are the same for the selected objects are displayed in the Property Editor, and the values of properties which are not the same are left blank. If you change a value in the Property Editor, the new value is assigned to all of the selected objects.

## Supported Properties

The properties assigned to an object vary based on the type of object.

### General

Name
Object name. Objects can be renamed in the Model Browser or Property Editor, or by using the right-click context menu.
Identify As
Part type in terms of wind tunnel testing: body, heat exchanger in/out/wall, or wheel. This option is also set by means of the Identify Parts tool and the right-click context menu.
Baffle
Baffles are two dimensional surfaces that are surrounded by fluid on all sides but do not combine with other surfaces to form a fluid volume. They are used to represent thin regions of solid material that are too costly to explicitly resolve. This option is also set by means of the right-click context menu.
Scale
The scale factor of the part with respect to the original geometry that was imported into VWT. This option is also set by means of the Scale tool.
Group (heat exchanger, wheels)
Identifies which wheel or heat-exchanger group this part belongs to. You can select different groups from the drop down list.

### Appearance

Visible
Indicates whether the selected object is visible (shown or hidden) in the modeling window.
Color
Indicates the color assigned to the object when it is displayed in the modeling window.

Click to create and assign custom colors.

Transparency
Transparency of the selected object, according to a percentage. By default, objects are zero percent transparent.
Display Style
Indicates how parts and assemblies are displayed in the modeling window. In addition to the default smooth shading display style, each part can be displayed as mesh lines, or as smooth shading with mesh lines.

### Inflow Velocity (Wind Tunnel Only)

Inflow speed
The velocity of air at the inlet to the wind tunnel. This velocity is also used as the wall velocity of belts and moving ground if activated.

### Boundary Layer Suction (Wind Tunnel Only)

Active
Activates the modeling of a boundary layer suction upstream of the point at which the boundary layer begins to grow.
Delta X to inflow
The distance from the inflow for which the ground should be treated as a slip wall to model boundary layer suction. The boundary layer is allowed to grow naturally downstream of this distance.

### Tunnel Properties (Wind Tunnel Only)

Length
Total length of the wind tunnel, typically designated in meters.
Width
Total width of the wind tunnel, typically designated in meters.
Height
Total height of the wind tunnel, typically designated in meters.

### Tunnel Extents (Wind Tunnel Only)

X Min, X Max, Y Min, Y Max, Z Min, Z Max
This read-only value indicates the extension of the wind tunnel with respect to each coordinate axis.
This is different from the Length, Width and Height settings in that it can comprise positive and negative values. For example, a wind tunnel that is four meters wide across its Y axis, but centered on the coordinate origin, would have a Y Min of -2m and a Y Max of 2m.

### Heat Exchanger Properties (Heat Exchangers Only)

Inertial Resistance
The inertial resistance coefficient (${R}_{i}$) used to determine the pressure drop across the porous media per the following equation:
$-\frac{dp}{dx}=\rho ·{R}_{v}·u+\rho ·{R}_{i}·{u}^{2}$
Where,
$\rho$
Density
$u$
Velocity
$p$
Pressure
$x$
Location coordinate
Viscous Resistance
The viscous resistance coefficient (${R}_{v}$) used to determine the pressure drop across the porous media per the following equation:
$-\frac{dp}{dx}=\rho ·{R}_{v}·u+\rho ·{R}_{i}·{u}^{2}$
Where,
$\rho$
Density
$u$
Velocity
$p$
Pressure
$x$
Location coordinate

### Permeability Direction (Heat Exchanger Only)

Direction X,Y,Z
Defines the direction in which the permeability is applied.

### Wheel RPM (Wheels Only)

Auto Calculate
Automatically calculate the angular velocity of the wheel based on the wind speed and location of wind tunnel ground plane.
Angular Velocity
Rate of rotation of the wheel.

### Wheel Center (Wheels Only)

Wheel Center X, Wheel Center Y, Wheel Center Z
Location of the wheel's center in the global coordinate system. The default center is computed based on the oriented bounding box of the part.

### Wheel Axis (Wheels Only)

Wheel Axis X, Wheel Axis Y, Wheel Axis Z
Wheel's axis of rotation in the global coordinate system. The default axis is computed based on the oriented bounding box of the part.