|
|
||
|
|
|
|
This and the next five slides are from the paper, "Optimum design of stiffened panels with substiffeners", by David Bushnell and Charles Rankin, AIAA 46th Structures, Structural Dynamics, and Materials Conference, Paper no. AIAA Paper 2005-1932, 2005, called "2005 PANDA2 paper in the next five slides.
This slide shows Fig. 5 from the 2005 PANDA2 paper. Here are STAGS results for inter-ring buckling of a perfect shell (Case name = testax4p, "p" for "perfect") obtained from a STAGS sub-domain model of a stiffened and sub-stiffened cylindrical shell under combined axial compression, external pressure, and in-plane shear.
The perfect shell was previously optimized by PANDA2 as perfect.
The combined loading used for all the configurations studied in the 2005 PANDA2 paper is:
Axial Resultant (lb/in), Nx Load Set A = -100000 lb/in
Hoop Resultant (lb/in), Ny Load Set A = -20000 lb/in
In-plane shear (lb/in), Nxy Load Set A = 20000 lb/in
Uniform pressure, (psi),p Load Set A = -200 psi (external pressure)
Zero loading in Load Set B.
Displayed here is a 3 x 9 major-bay sub-domain STAGS model in which the sub-stiffeners are smeared and the major stiffeners are modeled as flexible shell units. The STAGS 480 finite element is used.
Shown here is linear bifurcation buckling mode 1, buckling load factor, Pcr = 0.98903. This is inter-ring buckling.
Most of the STAGS models displayed in this slide show were generated automatically by PANDA2 and by GENOPT/BIGBOSOR4 processors.
Page 15 / 35