Analysis of Buckling Phenomena - FEA
ANALYSIS OF BUCKLING PHENOMENA
Aim :
To perform a buckling analysis on a cyclonic separator stand with and without a metallic stiffener on the legs of the stand and undergo design study and compare the results in the buckling factor of safety and other factors.
Description :
Buckling is the sudden change in shape of a structural component under load 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.
In this scenario, buckling analysis is done to the stand for a Cyclonic Separator for 2 cases (i.e)
Case 1 : Without stiffener
Case 2 : With stiffener
and following are the images of both the cyclonic seperator and the stand.
Case 1 : Without Stiffener
Material applied : Alloy Steel
Fixed geometry : Bottom face of the four legs of stand
Force : 150kN applied on the top face of the stand
Mesh : Solid fine mesh
Visualisation of Loads, Fixed geometry and mesh :
After undergoing Buckling analysis, the above attached Buckling amplitude plot was observed and the Buckling Factor of Safety was obtained as 9.3655 and by observations, the stand has been buckled. So, to improve the Buckling Factor of Safety and to make the stand more reliable, a design study for a case has been done for a stand with Stiffener.
Case 2 : With Stiffener
For this case, a stiffener was introduced between the legs of the stand and buckling analysis was done for various design study with stiffener at various positions. The best and optimal one which satisfy the minimum criteria, various other aspects is considered to be a better positioning of the stiffener for possessing high Buckling factor of safety.
Material applied : Alloy Steel
Fixed geometry : Bottom face of the four legs of stand
Force : 150kN applied on the top face of the stand
Mesh : Solid fine mesh
Visualisation of Loads, Fixed geometry and mesh :
With the stiffener placed at a distance of 1m from the top face of the stand and with thickness = 75mm(0.075m), the following buckling analysis was observed and the Buckling factor of safety obtained was 27.933
Design study :
A design study was conducted with variables as the offset distance between the top face of the stand and the stiffener, stiffener extrude distance along with few constraints and goals.
The variables, constraints and goals are as follows:
A total of 24 scenarios was calculated for the various variables and other aspects. Following are the results in each scenario
Out of all the scenarios, the optimal one was obtained for the Scenario 20 with the following parameters
Offset distance : 1m
Stiffener thickness : 0.1m (100mm)
Buckling Factor of Safety : 31.867
Conclusion :
From the 2 cases of buckling analysis such as with and without stiffener, both the cases are considered as a good design because the Buckling factor of safety were above 3 in each case but considering the long lasting feature and the durability to occupy more loads, the Case 2 : with stiffener holds good and the Buckling Factor of safety changed from 9.3655 to 31.867 with the introduction of stiffener at an appropriate and optimal position.