Aim:

To perform a buckling analysis on a cyclone separator stand by creating a metallic stiffener on the legs of the stand and run the analysis to find out the change in buckling factor of safety.

Theory:

In engineering, buckling is the sudden change in the shape of a structural component under loads such as the bowing of a column under compression or the wrinkling of a plate under shear. If a structure is subjected to a gradually increasing load when the load reaches a critical level, a member may suddenly change shape and the structure and component is said to have buckled.

Buckling may occur even though the stresses that develop in the structure are well below those needed to cause failure in the material of which the structure is composed. Further loading may cause significant and somewhat unpredictable deformations, possibly leading to complete loss of the member's load-carrying capacity. However, if the deformations that occur after buckling do not cause the complete collapse of that member, the member will continue to support the load that caused it to buckle. If the buckled member is part of a larger assemblage of components such as a building, any load applied to the buckled part of the structure beyond that which caused the member to buckle will be redistributed within the structure. Some aircraft are designed for thin skin panels to continue carrying load even in the buckled state.

Procedure:

• Import the cyclone separator file into the SOLIDWORKS, it opens as an assembly son suppress all the parts except the stand.
• Save the stand as a part file.
• Open the part file, and select the top plane to create the stiffener.
• The stiffener was created at 1000mm below the top face of the stand with a width of 75mm.
• Then create a new study from simulation option in SOLIDWORKS to carry out FEA of the stand.
• Define the material which is alloy steel.
• Fix the face of the bottom of the legs.
• The external load was defined, on the top face of stand i.e. 150KN.
• Then mesh was created.
• Then the setup was run.
• This setup results i.e. buckling factor of safety will be useful for taking reference for parametric study.
• Then design study was carried out for analysis of the buckling factor of safety at different positions of stiffener at the stand.

Results:

Units Unit system: SI (MKS) Length/Displacement mm Temperature Kelvin Angular velocity Rad/sec Pressure/Stress N/m^2

Design Study Setup Design Variables Name Type Value Units offset stifner Range with Step Min:250 Max:1750 Step:250 mm Constraints Sensor name Condition Bounds Units Study name Buckling Factor of Safety1 is greater than Min:25.000000 Buckling 1 Goals Name Goal Properties Weight Study name Buckling Factor of Safety1 Maximize Buckling Factor of Safety 10 Buckling 1

Study Results 9 of 9 scenarios ran successfully. Component name Units Current Initial Optimal Scenario1 Scenario2 offset stiffener mm 1750 1750 1000 250 500 Buckling Factor of Safety1 12.291012 12.291012 27.804258 12.142453 15.758519 Component name Units Scenario3 Scenario4 Scenario5 Scenario6 Scenario7 Offset stiffener mm 750 1000 1250 1500 1750 Buckling Factor of Safety1 21.317398 27.804258 21.846001 16.055376 12.291012

Conclusion: The optimum position of the stiffener to obtain maximum buckling factor of safety is at the middle of the stand i.e. 1000mm below the top face of the stand.