Objective: To determine stress distribution for bed frame taking into account the movements produced by forces at the three nodes - alternator, gear and engine. Thermal load is high at the engine.
Conclusions:
a. Structure was structually safe, but thermally vulnurable
b. The engine mounts needed to be strengthened in longitudinal direction to negate thermal deformations
c. The rest of the structure does not need to be so strong.1/10th of yield stress

Recommendations:
a. Thermal stresses were based on the assumption that Bed Frame stays at 20 degrees c. A detailed transient analysis may be done with heat storage affects and ambient convection
b. This can be followed by thermal stress analysis at various intervals to get accurate thermal stresses
c. Crack-initiation can be analysed if we attain peak stresses during one start-run-stop cycle of engine (calculated in transient run above). This information can also initiate a fatigue study to estimate the life of bed frame.
d. Adequate safety factors should be used on account of above approximation.

Methodology:

Modeling The model (bed frame) is imported from Pro-E, Catia, Unigraphics, Solidworks environment
Meshing Solid Mesh was generated in ANSYS. Higher order brick elements and higher order tetrahedral were used for meshing Transition pyramid meshing was done at hex to tetrahedral interfaces. Permanent contacts were defined wherever node-to-node connectivity was not maintained
Loading boundary conditions In the materials library the required material was selected, applied and the various coefficents and constants were fed. Spring elements were defined to model mounts for supporting the bed frame at base. These mounts were provided stiffness in all 3 directions. Engine, gearbox and alternator were modeled as solid blocks to adequately represent their mass. Centre of gravity was calculated.