Ansys Mechanical Nonlinear Structural Simulation

Workshop 2a – Nonlinear Contact Analysis of a Ring Gear and Housing Assembly with Interference

This model involves calculating stresses in the housing and ring gear due to initial interference. The initial interference in combination with friction holds the ring gear securely in the housing. This workshop provides additional practice on setting up, solving, and postprocessing nonlinear contact problems.

Workshop 2b – Nonlinear Contact Analysis of a Cell Phone Antenna Snap Fit 

The problem initially does not converge, and the student adjusts nonlinear model parameters to make it converge. The model then gives incorrect answers, and the student resolves that problem. The student also uses a commands object to control whether the symmetric or unsymmetric solver is used in order to improve solution performance. In this workshop the student uses a nonlinear contact solution with friction to simulate a cell phone antenna snap fit problem.   

Workshop 3a – Nonlinear Contact Analysis of a Ring Gear and Housing Assembly with Plasticity

This model involves calculating stresses in the housing and ring gear due to initial interference. This model expands upon workshop 2b and introduces plasticity to the model. Students post-process total strain to determine if the interference specification satisfies the design criteria of maximum 1% total strain.

Workshop 3b – 2D Plasticity Analysis of a Threaded Connection including Nonlinear Contact and Elastic-Plastic Behavior

This model represents a four part threaded connection assembly. Nonlinear contact is used to model interaction of the threads and the mating surfaces of the other parts. Students define a multilinear elastic-plastic model and calculate plastic and total strains.

Workshop 4a – Linear and Nonlinear Buckling Analysis of a Steel Column

This assembly is a C-channel shaped column with a cap and a base, all composed of A36 steel. A downward vertical load is applied at the top of the column that will cause it to buckle. DRD introduces the methodology of solving a buckling problem: from a simple Eigenvalue, or linear buckling analysis to a nonlinear buckling analysis where an elastic-plastic material model is employed to simulate permanent deflection and local instability. Students will learn the workflow analysts typically use to solve buckling problems.

Workshop 4b – Snap Through Analysis of a Spherical Tank Section Using Stabilization

A section of a curved tank needs to be analyzed to check deflections and stress. This geometry will buckle when a sufficient load magnitude is applied. Solution restarts and the stabilization feature is utilized in this workshop.

Workshop 5a – 2D Axisymmetric Analysis of a Hyperelastic Rubber Seal with Nonlinear Contact

This four part assembly model has two rubber parts modeled using a hyperelastic material model. Students import experimental data into the Workbench Engineering Data module and curve fit it to create Mooney-Rivlin constants. Initially the model does not converge, and students must modify the model to get it to converge. The model also provides an opportunity for students to experiment with different nonlinear contact formulations including pure penalty, augmented Lagrange, and normal Lagrange.

Workshop 5b – 2D Axisymmetric Analysis of a Hyperelastic O-ring with Fluid Pressure Penetration Loading

This model is comprised of three parts – a cylinder, ring, and seal. The cylinder enters the bore and contacts the seal to produce pressure between the cylinder and ring. Ideally this pressure would be great enough to keep fluids from breaking the seal. The second step applies fluid pressure to the exposed portion of the seal and continues to be applied to the portions of the seal that ‘peel away’ from the cylinder or ring. This fluid pressure penetration capability in Ansys is critical in determining seal performance.

Workshop 5c – 2D Axisymmetric Analysis of a Hyperelastic O-ring with Nonlinear Contact, Using Nonlinear Adaptive Remeshing (NLAD)

This model contains a tube, sleeve, o-ring and swaging body. The swaging body is pushed down, causing the tube to be plastically deformed into the seal, which is a hyperelastic body. A pressure is applied to the inside of the tube at a subsequent time. The o-ring undergoes severe deformation; the Nonlinear Adaptive Remeshing technique is used to remesh the model during the solve process automatically to get a completed solution, rather than the user remeshing manually if the model fails to solve.

Workshop 6a – Nonlinear Contact Analysis of Steel Enclosure with Bolt Pretension

This four part assembly is held together with a pretensioned bolt. Students use Simulation bolt pretension to load the model. The objective of the model is for students to gain a thorough understanding of Simulation bolt pretension. This model also provides additional practice in modeling nonlinear contact.

Workshop 6b – Analysis of a Pump Fluid End with Bolt Pretension

This pump assembly is held together with four pretensioned bolts. Students use load steps to sequentially pretension the bolts one step at a time and then apply additional loads.

Workshop 7 – Stress Analysis of Gearbox Casing Subjected to Static Loads including Plasticity

This gearbox casing is subjected to force and torque loading and the objective is to determine peak stresses in the structure. Students will use the submodeling process, which is based on St. Venant’s Principle, to build a coarse-grid model, take the displacements from locations within the coarse-grid model and apply them to a fine-grid model boundaries. Use of plasticity will be required to get accurate stress beyond the yield strength of the material.

Ansys SpaceClaim will be used to create the fine-grid model using the coarse-grid model as input.

Workshop 8 – Nonlinear Contact Analysis of a Control Valve including Gasket Behavior

This control valve has two gaskets, and the objective of the analysis is to optimize the gasket design. Workbench does not yet have gasket elements, so students use DRD developed commands objects to add gasket elements to the model. The model also involves bolt pretension, pressure, mechanism forces, and thermal loads. The model requires linear and nonlinear contact types. Students define temperature dependent material properties.

The initial design does not have a viable gasket design, and students use a design parameter and DesignModeler to modify the design to achieve an optimum gasket design.