About the Crane Hook Example

This example shows a more general optimization setup using sensitivity based algorithms for shape optimization. Thus, the volume can be minimized considering as well stress and frequency constraints.

About the Model

The component optimized in this example is a simple model of a crane hook. The model is generated by extrusion of a 2D contour into the z-direction. The hexahedral mesh is also generated by extrusion.



The model of the hook for static analysis is stressed by the forces of a cable. The crane hook is supported by the upper bore hole. To keep the model simple, no other contacts or swinging motions in the bore hole are taken into account. In the modal analysis the first 5 eigenvalues are to be considered.

Load Case 1:

Load Case 2:

The design area for this task consists of the nodes on the outer surfaces (front and rear) depicted in red in the figure (node set DESIGN_NODES ). The mesh smooth area (in blue) consists of all elements adjacent to the design nodes and their extrusion in the z-direction together with some additional layers of elements at the top (element set MESH_SMOOTH_ELEM ; see the figure).



Procedure Summary

Note: This example is only supported for Tosca Structure.gui and Tosca Structure 2016.

Model:

cranehook_static.ext

cranehook_modal.ext
Design Area:

Node set design_nodes
Design Variable Constraint: Maximum optimization displacement of the design nodes to 10
Design Variable Constraint: Boundary conditions as restrictions for the optimization displacement
Mesh Smooth:

Mesh smooth area: MESH_SMOOTH_ELEM
Objective: Minimize the volume
Constraint:

The fifth natural eigenfrequency must be increased by at least 110% compared to the initial value
Constraint:

The maximum Mises stress for the first load case (step) in the group STRESS_NODES must be decreased by at least 10% compared to the initial value
Stop Conditions: 15 iterations