Parametric data generation and Grid dependency tests on a bevel gear geometry

Grid dependency test is used to validate the dependency of results on mesh size used for solving the mathematical model of problem under consideration.

Objective:

Bevel gear geometry was used to explain grid dependency for different mesh sizes.

Procedure:

• Given bevel gear geometry was imported to spaceclaim GUI
• Both parts were renamed as Small gear and Big gear for identification and reference purpose
• Frictional contact was setup between the mating faces of both gears
• Symmetric behaviour is used which implies that contact and target can be interchanged
• Augmented Lagrange formulation is used which provides faster convergence
• Adjust to touch interface treatment is provided
• Revolute joints are setup between gears and ground to simulate gear revolutions
• Mesh size of 4 mm is provided and face sizing of 1.75 mm is applied to mating faces under consideration
• Problem is setup in 6 steps, auto stepping time is switched ON. Auto stepping time optimizes the solution time by converging the solution to previous converged point if simulation remains un coverged in a step.
• Large deflections is switched ON which takes large strains during simulation into consideration
• Torsional moment of 100Nmm is provided for big gear through all 6 steps. Rotation of 20 degree per step is provided for small gear.
• Simulation is run to find required results.
• Total deformation, Maximum stress and maximum strain for different mesh sizes can be found using parametric method.
• Mesh size is set up as input parameter. Total deformation, Von mises stress and equivalent elastic strain are set up as output parameters.
• New desgin points are updated and required results are found

Results discussion:

Simulation results for mesh size of 4mm is discussed below.

Maximum equivalent stress of 2.717 MPa is experienced at the point of contact of two gears as expected.

Maximum equivalent strain of 1.8244 e-5 occurs at point of contact as shown.

Total deformation of 47.84 mm is found as shown below.

Paramertic datas are generated for 5mm and 6mm mesh sizes and are tabulated below.

Learnings from this exercise:

Parametric data generation and significance of grid dependency test are understood from this assignment.