This is an Early Access feature that is still under development. View the Luminary Cloud Early Access Terms.

Specifying motion requires you to define a reference frame, the motion of that frame, and the volumes and surfaces that move with the reference frame.

When creating a new reference frame, you can choose from the following types:

Rotation to define rotational motion.
Translation to define translational motion.
Frame should be used when there is no relative motion to the parent frame. These frames can be useful for positioning and orienting child frames, or for outputs that require direction or point specifications.
‍Body Frame defines body orientation and is used to define far field flow angles and force direction for some Surface output quantities such as lift, drag, and sideforce. It is commonly used in aircraft and automotive aerodynamics simulations. See Defining Body Orientation for more information on using this frame type.

When specifying motion, the following properties need to be set to define the frame, its motion, and any attached geometry:

Parent	Select the parent frame. The default setting is Global and the dropdown will populate with frames you have created. Problems are always initialized with a Global frame whose Origin and Orientation are determined by the mesh or geometry package used to create the entity. If this is the first frame you are creating, Global will be the only option. The Global frame is the parent of all frames and may not have motion.
Origin	This property defines the origin (0,0,0) of the local frame in the parent frame coordinates system. You can quickly assign Origin to the centroid of the selected geometry by clicking the circle icon at the top of the Properties panel.
Orientation	This property is specified by a set of extrinsic Euler angles, first rotating about the x-, then y-, then z-axes of the parent frame.
Type	This property defines the type of motion (rotational or translational). For rotational motion, you will need to specify a Rotation Vector, where the three vector elements define the axis of rotation and the vector magnitude is the rotational velocity. For translational motion, you will need to specify a Translation Vector, where the three vector elements define the direction and the vector magnitude dictates the speed.
Formulation (transient simulations only)	This property defines how volumes move in transient simulations. Moving Mesh: Also known as the Sliding Mesh approach. The mesh position is updated at every time step. We recommend this setting if the timescales you are most interested in are smaller than the time it takes for one revolution to complete. Moving Frame: Also known as Moving Reference Frame (MRF) or Frozen Rotor approach. With this option, the mesh does not move and instead the governing equations are solved in a moving reference frame that mimics the intended motion. We recommend this setting if the timescales you're most interested in are larger than the time it takes to complete one revolution.
Geometry	Volumes and surfaces that move need to be assigned to a frame with motion.

Important: Both volumes and surfaces need to be assigned to a frame in order to identify if a surface moves in the same way as the volume it belongs to, or whether that surface should be treated as a Moving Wall.

When you create a frame, a representation of the frame's coordinate system axes will show on your model in the 3D Viewer. Changing Origin and Orientation will move the axes to help you place it in the correct location. When you create a frame that is the child of another frame, two sets of axes will show. The larger set is the one you are currently manipulating while the smaller set belongs to the parent frame.

Restrictions

The Global Frame cannot have an altered Origin or Orientation.
The Global Frame cannot have any motion.
The parent of the Body Frame must be the Global Frame.
Volumes and surfaces can only be members of one frame.
Only surfaces belonging to wall boundary conditions can be assigned to a different frame than the volume they belong to. All other surfaces must share a frame with the volume they enclose.

Basic Controls

Define Motion

Define Body Orientation

Boundary Condition Types