Week 5 Sphere pressing on a plate
1. PROBLEM STATEMENT:
A Sphere is pressed over a flat plate by providing a displacement load of –4mm in Y-axis, which will help to press the sphere over a flat plate. The plastic strain is analyzed for a flat plate.
The plastic strain value will help to understand, if the plate deformation is permanent or elastic.
2. MODEL
The above model is the one fourth part of a completely symmetric Sphere over a flat plate..
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1. SYMMETRIC MODEL CONDITION:
In this case, both the sphere can be axisymmetric. Hence, this property of the geometry can be used inorder to reduce the computational time by analyzing the one fourth of the model.
2. Material:
The material used in similar for both of Sphere & Flat plate. However, the flat plate is provided with the non-linear material property, as the plastic strain is to be evaluated in that region.
3. CONTACTS:
A non-linear frictional contact is defined between the sphere & plate. However, the plate is defined as the Target & sphere as contact. The main reason being, the contact component cannot penetrate in to the target.
1. LOADING CONDITION:
In this analysis, the top surface of the sphere is provided with a displacement of -4mm in the vertical direction, such that it applies a compressive load on the fixed plate.
However, the loading is provided in 4 steps. Such that the sphere compresses the flat plate and returns to its original position. In order to understand the strain- state of the plate.
Also, the flat plate is fixed at the bottom to replicate the placement of the flat plate on the ground.
1. Analysis Settings:
In the analysis settings: the steps are increased up to 4, in order apply the loading condition, without facing any convergence issues. The solver type used is Direct, with a large deflection turned on. As there is a plastic deformation expected in the analysis.
Direct solver is preferred, mostly if the nodes is less than 300,000 for a 3D model as it is more efficient, however it uses ten times more memory than a Iterative solver.
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2. Post Processing / Results:
The main aim of performing this simulation is to find out, whether the flat plate experience an elastic or plastic deformation. In order to analyze this, we generate a post processing results for Plastic strains on the plate.
Plastic deformation = 1.638
Conclusion:
Due to the compressive load of the sphere over the flat plate, the plate undergoes a plastic deformation. The maximum deformation in negative y-axis obtained in -3.36mm.