INTRODUCTION 2
METHODS 2
Safe model 2
Light model 3
Material parameters 3
Analysis Methodolgy 3
RESULTS 4
Safe design 4
1. Displacement results 4
2. Stress results 4
Meshing 5
Light model: 6
1. Displacement results: 6
2. Stress results: 6
Meshing 7
DISCUSSION 8
INTRODUCTION
A project was launched to use Finite Element Analysis to design two models, safe and light, to support an 18kg load and at the same time allow a block with the same dimensions as the mass to pass underneath the model structures and be placed at the under the centre of mass of the load placed on top. The block was made to pass through the structures in the orientation shown in Figure 1. The project aims for both these models to be as …show more content…
The mesh global size was changed from 9 (coarse mesh) to 1 (fine mesh) in increments of 0.5 and a graph was derived from this. The graph (Fig. 8) was a plot of the stress at the bottom face of the support beam against the number of elements in the mesh for each mesh global size value.
Mesh Convergence Analysis for Safe model (Fig. 8)
This shows that the stress value converged at a value of 6.001 MPa. The convergence point is indicated by a ring on the corresponding data points of the graph. The corresponding mesh global size for this iteration was 3 mm. Hence, this value was used to get results for the FEA.
Light model:
1. Displacement results: The displacement results for the light model were generated from the Solidworks software just as the safe model was. The results also showed that the displacements in the light model were higher than that of the safe model. The results for the light model showed that maximum displacement in the model was seen on the bottom face of the support beam of the structure. This corresponds with the results of the safe …show more content…
The grain of the two layers was observed and the wood grain for the two layers was seen to be in the same direction. This has an effect how the wood would react to compression and buckling when compared to plywood with wood grain in separate directions. The plywood provided would be weaker in handling compression and would hence buckle more easily under the same load cases as the latter. The joints used in models also have an effect on the rigidity of the structure. The traditional butt joint would not have been appropriate for the design of the two model as it is highly dependent on glue. The models were hence made with lap joints which provide higher structural integrity for the models rather than depending on glue for the