Create and Edit Space

Space is a three-dimensional, acoustic element supporting acoustic modes.

  1. From the Model ribbon, click the Acoustic > Space tool.
    Figure 1.


  2. From the guide bar, select one of the following to create space.
    OptionDescription
    Bounding
    1. From the guide bar, select Bounding for properly closed entities, either surfaces or SEA entities like a plate or shell.
      Figure 2.


    2. Click a Surface, Plate, or Shell subsystem. If all subsystems or surfaces create a closed entity, then it creates a cavity.
    Drag
    1. From the guide bar, select Drag for extruding any surface/SEA structural 2D entities to create a cavity.
      Figure 3.


    2. Select the surfaces to drag.
    3. Use the Guides option or the microdialog to align the cavity's direction.
      Figure 4.


    4. From the guide bar, click to define advanced options.
    Projection
    1. From the guide bar, select Projection to extrude multiple subsystems to a fixed plane.
    2. From the drop-down menu, select Surfaces or SEA Subsystems to select multiple surfaces or subsystems that need to be dragged.
    3. Use the Guides option or the microdialog to align the cavity's direction.
      Figure 5.


    4. Click and select Merge cavities at shared surfaces to get a single cavity.
      Important: The cavity created through Projection cannot be reversed, as Undo is not an available option. You must delete and recreate it.
      Note: You may need to resolve some connection problems manually.
      Figure 6. Typical result
  3. Once you define a properly closed entity, a microdialog is displayed, which you can use to assign properties, , and damping, .
    Figure 7.


    Figure 8.


    Figure 9.


  4. Specify the space name in the field.
  5. Click and to assign properties and damping, respectively. Click when finished.
  6. Click Create to create space.
    Figure 10.


    The parameters required to create a space subsystem are updated.
  7. From the microdialog, click to edit the subsystem and update the parameters
    Figure 11.


    Figure 12. Space Entity Editor


    Name
    Specify unique name.
    ID
    Specify unique ID.
    Config
    Specify the element type.
    Property
    Specify the property parameter based on the element type.
    Damping
    Specify damping to the subsystem.
    Geometry
    Based on the element type, update the geometry parameters.
    Generally, the geometry is automatically updated from the user-defined geometry. You can modify the geometry information by clicking User Defined as shown below.
    Figure 13.


    Noise Control Treatments
    Define a Noise Control Treatment on cavity surfaces, which is further explained in NCT Application.
    Absorption
    Define or select the number of absorptions to be defined.
    There are two ways to define absorption:
    1. Global Absorption If you define Global Absorption, then absorption is applied to cavity faces for which either NCT or absorption definition is not defined, and the effective area is automatically calculated.
    2. Define the absorption for each face under the absorption option, define the number of absorptions to be defined apart from the global absorption using the Absorption Count.
    Absorption Faces
    Define or select the number of absorptions to be defined.
    Absorption Faces
    Define or select the absorption entity.
    Abs 1 Surface
    Select the surfaces of the cavity to which absorption needs to defined.
    Area 1
    Define the area to overwrite the area calculated from the surface, if needed.
    Realized NCT Absorptions
    Realized NCT absorptions are automatically added after solving. NCT absorption is added only when there are NCTs to SEA structural subsystems (plate and shell) connected to cavity.
    Subsystem Options
    For experienced users, expand the Subsystem Options to change the default choices for the SEA Subsystems for all element types. For certain structural element types, use these options to adjust the default bending stiffness or conductance of the element and add non-structural mass, component mass, or fluid loading to the element when the options have been changed.
    Damping
    Assign a damping model to the element. From the Damping field drop-down menu, select a damping model. This list contains all predefined models which apply to the current element type. Click to display advanced damping options that you can use to define additional damping models.
    Properties
    Assign a property model to the element. From the Property field drop-down menu, select a property model. The element materials and cross-sectional parameters defined in the selected Property record are displayed. Property records can be used to simplify the model definition in cases where many elements have the same properties. Click to display advanced property options that you can use to define additional property models.
    Figure 14.