The Syrian airfield prepare for reception of military aircraft of China
The latest news about fast emergence in borders of Syria of navy of China encouraged Syrians and res[...]
Structural Analysis of General Shells (STAGS) (Marshall and Langley, 1960s-present)
Structural Analysis of General Shells (STAGS) evolved from early shell analysis codes developed by Lockheed Palo Alto Research Laboratory and sponsored by the NASA Marshall Space Flight Center between 1963 and 1968, with subsequent development funded primarily from Langley.
B. O. "Bo” Almroth of Lockheed was the principal developer. The name STAGS seems to have first appeared around 1970.[998] Thus, STAGS ini-^^^B^8 tial development was nearly concurrent with that of NASTRAN. While NASTRAN development aimed to stem the proliferation of analysis codes, and of shell analysis codes in particular, NASTRAN did not initially provide the full capability needed to replace such codes. In particular, STAGS from the beginning included nonlinear capability that was found necessary in the accurate modeling of shells with cutouts. In the mid – to late 1970s, STAGS was released publicly, with user manuals. "Under contract with NASA, STAGS has been converted from being more or less a pure research tool into a code that is suitable for use by the public for practical engineering analysis. Suggestions from NASA – Langley have resulted in considerable enhancement of the code and are to some degree the cause of its increasing popularity. . . . User reaction consistently seems to indicate that the run time with STAGS is surprisingly low in comparison to comparable codes. A STAGS input deck is usually compact and time for its preparation is short.”[999] STAGS continued to be enhanced through the 1980s (as STAGS-C1, actually a family of versions), offering unique capabilities for modeling total collapse of structures and problems that bifurcate into multiple possible solutions.[1000] It was apparently popular and widely used. For example, in 1990, Engineering Dynamics, Inc., of Kenner, LA, used STAGS-C1 to model and verify a repair design for a damaged offshore oil platform.[1001]
STAGS Version 5.0 was released in 2006, and STAGS is still used for failure analysis, analysis of damaged structures, and similar problems.[1002]
4) Nonlinear Structures: PANES (1975) and AGGIE-I (1980) (Marshall)
Program for Analysis of Nonlinear Equilibrium and Stability (PANES) was developed for structural problems involving geometric and/or material nonlinear characteristics. AGGIE-I was a more comprehensive code capable of solving larger and more general problems, also involving geometric or material nonlinearities.[1003]
5) Finite Element Modeling of Piping Systems (Stennis)
While Stennis is not active in structural methods research, there have been some activities applying finite element and structural health monitoring techniques to the complex fuel distribution systems at the facility. One such effort was presented at the 27th Joint Propulsion Conference in Sacramento, CA, in 1991: "A set of PC-based computational Dynamic Fluid Flow Simulation models is presented for modeling facility gas and cryogenic systems. . . . A set of COSMIC NASTRAN-based finite element models is also presented to evaluate the loads and stresses on test facility piping systems from fluid and gaseous effects, thermal chill down, and occasional wind loads. The models are based on Apple Macintosh software which makes it possible to change numerous parameters.”[1004] NASA was, in this case, its own spinoff technology customer.
Appendix C:
