Virtualwind Entities
Entities
Virtualwind incorporates various structural entities, such as Buildings, Canopies, and Terrain. These entities interact with the wind in the computational domain. The entity Atmospheric Condition is used to represent the wind and related settings necessary for a simulation study. The entity Domain is used to represent the computational domain within which the structures are processed and the physical equations are solved.
While entities of Building, Canopy, and Terrain are usually loaded from the input VWS file, other entities, such as Smokebombs* and Tracer Particle Generators*, can be directly generated from Virtualwind. A Smokebomb simulates a source of smoke whose properties can be specified and the way it disperses in the air can be monitored (by adding a Domain Fluid Species Monitor). A Tracer Particle Generator specifies a position in the Domain where you can release massless particles at a certain frequency and in a certain period of time. Then through its Monitor ( called Tracer Particle Monitor) you can watch their trajectories in the air flow. These two types of entities provide useful means for investigating the air flow and its interaction with the environment.
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Entities can be created and manipulated via the Entities menu which can be accessed through the main window as shown above. You can have multiple instances of Building, Canopy, Smokebomb, or Tracer Particle Generator within the same simulation study. However, the current version of Virtualwind allows only one instance of Terrain, Atmospheric Condition, and Domain, respectively, in one simulation study. In order to run the simulation, it is mandatory that you have entities of Atmospheric Condition and Domain in your study however, none of the other entities are required to be present.
Definitions and detailed explanations for each entity type can be accessed via the links located at the bottom of this page.
Managers
Within Virtualwind, entities of the same type are grouped together and managed by their corresponding managers. There are Building Manager to manage all the buildings, Canopy Manager to manage all the canopies, Terrain Manager to manage the terrain, Smokebomb Manager to manage all the Smokebombs, and TracerParticleGenerator Manager to manage all the Tracer Particle Generators. The following table lists the current Managers along with their managed entities.
Manager | Entities |
---|---|
Building Manager | Buildings |
Canopy Manager | Canopies |
Terrain Manager | Terrain |
Smokebomb Manager | Smokebombs |
TracerParticleGenerator Manager | Tracer Particle Generators |
Entities of Atmospheric Condition and Domain do not have managers, as there is only one instance allowed for each of them in a Virtualwind simulation.
The Entity Tree
Entities are organized in a tree structure under the Entities & Monitors tab in the main window. The figure below shows an example simulation that incoporates the supported of manager and entity types. As can be seen from the expanded view of the Building Manager item, both the manager and the entity (Building), have two children items: the Model and the Actor. In general, the model item represents the internal status of the instance and the actor item controls how the instance appears in the viewport. For example, the particular Building can be shaded (surface rendered), or shown as a wireframe, etc.
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Entities also consist of Parts as noted in the above figure. The example illustrated here has three Buildings in the study and the third Building consists of 10 Parts. At the Part level, there are also Model and Actor items in the tree associated with each Part.
Pop-up menus
Some of the items in the entity tree have a small green arrow next to them. This indicates that if you right-click on these items, a pop-up menu will appear allowing you to subsequently select operations that can be performed on the particular item.
Mouse over, selection, and wireframe
When you mouse over an item in the entity tree, it will be highlighted in red and if it has a corresponding representation in the viewport, its wireframe will be highlighted in green. Some items in the entity tree are also selectable. When selected, the item is highlighted with a blue background and the wireframe of its corresponding representation in the viewport will be highlighted in blue.
When an item is both mouse overed and selected in the entity tree, it will show as being mouse overed as the mouse over action takes priority over selection.
Generally, you also have the option to show an entity in the viewport by its wireframe (refer to the links below for a description of each entity type). If you choose to hide its wireframe (turn off its wireframe state) but you can still see it in the viewport, more than likely, this item is actually selected or mouse overed in the entity tree.