What is in this Article?

1. Introduction

2. Rotary Acceleration Load

3. Condition of Rotary Acceleration Load

4. How to create Rotary Acceleration Load

1. Introduction

Create Load Case & Load is a main steps of Modeling process. This article provides information about a type of load: Rotary Acceleration load which represents for affection of angular velocity onto the structure. Following the topics, users will be prepared an overview about the Rotary Acceleration Load in Akselos Modeler, how to use it and control all the Rotary Acceleration Load parameters.

Add Load Cases is a part of the Modeling steps in Akselos Workflow to build any simulation model. 

Terminologies

2. Rotary Acceleration Load

Rotary acceleration is the rate of change of angular velocity, or how quickly a rotating object is speeding up or slowing down. It is caused by a net torque applied to the individual or complete structure.

* Firstly, see the article - How to add Loads to your simulation model.

Figure 1. Rotary Acceleration applied on a Floating Wind model

This type of load is used to apply rotary acceleration defined on the shell's subdomains or solid’s subdomains.

Figure 2. Shell Rotary Acceleration is applied on shell’s subdomain

Figure 3. Rotary Acceleration is applied on solid’s subdomain

Mesh importer default ID convention: Rotary Acceleration Operator is assigned for mesh blocks in any ID, with turning on the Rotary Acceleration for Shell and Solid option in the mesh Importer.

Figure 4. Turning on the Rotary Acceleration Load for Shell and Solid option when importing components

Rotary Acceleration Load Parameters

For the rotary factor, the parameters of load must contain the referent point and direction for rotating. The magnitude of load and the direction are combined in one parameter (rot_accel_x/y/z).

The parameters of the Rotary Acceleration are as shown in the figure below, including:

• Stored Selection: the stored selection of subdomains that the load applies on.
• Load Name: Shell Rotary Acceleration/ Material Rotary Acceleration.
• center_of_rotation_x : indicating the fixed position (in m) relative to the origin coordinate in global x-direction (users input the value).
• center_of_rotation_y : indicating the fixed position (in m) relative to the origin coordinate in global y-direction (users input the value).
• center_of_rotation_z : indicating the fixed position (in m) relative to the origin coordinate in global z-direction (users input the value).
• mass_density : indicating material density (in kg/m^3) (only available with Shell components)
• rot_accel_x : indicating the component's rotational velocity (in rad/s^2) in x-direction (users input the value).
• rot_accel_y : indicating the component's rotational velocity (in rad/s^2) in y-direction (users input the value).
• rot_accel_z : indicating the component's rotational velocity (in rad/s^2) in z-direction (users input the value).

Figure 5. Parameters of the Shell Rotary Acceleration applied on shell’s subdomain

Figure 6. Parameters of the Rotary Acceleration applied on solid’s subdomain

This formula is used for Rotary Acceleration Load:

Figure 7. Angular Velocity demonstration

3. Condition of Rotary Acceleration Load

For any load type, there must be an Operator on the Component to define the load type which will be applied on that component. The operator for Rotary Acceleration Load is material_acceleration_rotary and can be created while importing mesh file (the sidesets are already set) or directly created in Akselos Modeler.

Figure 8 & 9  will show these operator types:

Figure 8. Rotary Acceleration Operator when importing the solid component

Figure 10. Creating Rotary Acceleration Operator in Akselos Modeler

In Akselos Modeler, there must be a target that the load will be applied on. In this case, the targets for loads are stored selections. The stored selections for Rotary Acceleration Load are Subdomain selections. See a stored selection for Rotary Acceleration Load below.

Figure 11. Stored selections for Rotary Acceleration load

4. How to create Rotary Acceleration Load

Follow the steps to create and set up a Rotary Acceleration Load.

STEP 1: On the Model Tree, right-click on Load Cases → select Add Load Case.

Figure 12. Add Load Case

STEP 2: Right-click on New Load Case → select Add Load …

Figure 13. Add Load

STEP 3: On New Load Case / Load dialog, select Material Volume Load → Click on the Save button.

Figure 14. Add Material Acceleration Load

STEP 4: On the new Material Volume Load 1 → Set Stored Selection: All_components or All_subdomains which are already created.

STEP 5: On Other Properties → Set value(s) for parameters.

Figure 15. Set parameters for load

Some Related Articles:

• Stored Selections
• How to add Loads to your simulation model