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User's guide to computer programs JET 5A and CIVM-JET 5B to calculate the large elastic-plastic dynamically-induced deformations of multilayer partial and/or complete structural ringsThese structural ring deflections lie essentially in one plane and, hence, are called two-dimensional (2-d). The structural rings may be complete or partial; the former may be regarded as representing a fragment containment ring while the latter may be viewed as a 2-d fragment-deflector structure. These two types of rings may be either free or supported in various ways (pinned-fixed, locally clamped, elastic-foundation supported, mounting-bracket supported, etc.). The initial geometry of each ring may be circular or arbitrarily curved; uniform-thickness or variable-thickness rings may be analyzed. Strain-hardening and strain-rate effects of initially-isotropic material are taken into account. An approximate analysis utilizing kinetic energy and momentum conservation relations is used to predict the after-impact velocities of each fragment and of the impact-affected region of the ring; this procedure is termed the collision-imparted velocity method (CIVM) and is used in the CIVM-JET 5 B program. This imparted-velocity information is used in conjunction with a finite-element structural response computation code to predict the transient, large-deflection, elastic-plastic responses of the ring. Similarly, the equations of motion of each fragment are solved in small steps in time. Provisions are made in the CIVM-JET 5B code to analyze structural ring response to impact attack by from 1 to 3 fragments, each with its own size, mass, translational velocity components, and rotational velocity. The effects of friction between each fragment and the impacted ring are included.
Document ID
19790010172
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Wu, R. W. H.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Stagliano, T. R.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Witmer, E. A.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Spilker, R. L.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Date Acquired
September 3, 2013
Publication Date
November 1, 1978
Subject Category
Structural Mechanics
Report/Patent Number
NASA-CR-159484
ASRL-TR-154-10
Accession Number
79N18343
Funding Number(s)
CONTRACT_GRANT: NGR-22-009-339
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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