### Abstract

A novel approach termed as the hybrid displacement-strain based normalized time weighted residual approach is presented in this exposition to accurately solve nonlinear structural dynamic problems. The current work concentrates on the design of a family of conserving time operators which preserve energy, linear and angular momentum conservation properties via this new innovative approach to solve nonlinear dynamic problems. The focus of this work is on Generalized Single Step Single Solve (GSSSS) computational algorithms which encompass the entire framework of those termed as linear multi-step (LMS) methods with unconditional stability and second-order accuracy which are most commonly used for such applications. In general, there exist three roots for LMS based methods, namely, the two principal roots ρ_{1∞}, ρ_{2∞}, and the spurious root ρ_{3∞}. The LMS framework is comprised of two distinct algorithmic structures termed as constrained U and V algorithms. Specifically, it is shown that in the sense of LMS methods, the implementation of V0 algorithms (zero oder velocity overshoot behavior) via the hybrid displacement-strain based normalized weighted residual approach (no external constraints on energy are imposed) with ({ρ_{1∞}, ρ_{2∞}, ρ_{3∞}} = {1.00,1.00, any ρ_{3∞} ∈ [0.00,1.00]} readily conserve energy, linear momentum and angular momentum. Although the displacement and velocity are independent of ρ_{3∞}, it is shown and proved that different choices of ρ_{3∞} gives different values of acceleration at every time step, thus yielding a different algorithm within the family. Nevertheless, in the sense of LMS methods, the entire family results in energy and momentum conserving algorithms regardless of the selection of ρ_{3∞} since only displacement and velocity participate in the algorithm as clearly presented in this paper. Numerious numerical illustration are presented to demonstrate the fundamental principles.

Original language | English (US) |
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Journal | Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference |

State | Published - Jul 4 2008 |

Event | 49th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference - Schaumburg, IL, United States Duration: Apr 7 2008 → Apr 10 2008 |

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*Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference*.

**Algorithms by design : A novel normalized time weighted residual approach and design of a family of energy-momentum conserving algorithms for nonlinear structural dynamics.** / Masuri, S.; Hoitink, A.; Zhou, X.; Tamma, K. K.

Research output: Contribution to journal › Conference article

*Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference*.

}

TY - JOUR

T1 - Algorithms by design

T2 - A novel normalized time weighted residual approach and design of a family of energy-momentum conserving algorithms for nonlinear structural dynamics

AU - Masuri, S.

AU - Hoitink, A.

AU - Zhou, X.

AU - Tamma, K. K.

PY - 2008/7/4

Y1 - 2008/7/4

N2 - A novel approach termed as the hybrid displacement-strain based normalized time weighted residual approach is presented in this exposition to accurately solve nonlinear structural dynamic problems. The current work concentrates on the design of a family of conserving time operators which preserve energy, linear and angular momentum conservation properties via this new innovative approach to solve nonlinear dynamic problems. The focus of this work is on Generalized Single Step Single Solve (GSSSS) computational algorithms which encompass the entire framework of those termed as linear multi-step (LMS) methods with unconditional stability and second-order accuracy which are most commonly used for such applications. In general, there exist three roots for LMS based methods, namely, the two principal roots ρ1∞, ρ2∞, and the spurious root ρ3∞. The LMS framework is comprised of two distinct algorithmic structures termed as constrained U and V algorithms. Specifically, it is shown that in the sense of LMS methods, the implementation of V0 algorithms (zero oder velocity overshoot behavior) via the hybrid displacement-strain based normalized weighted residual approach (no external constraints on energy are imposed) with ({ρ1∞, ρ2∞, ρ3∞} = {1.00,1.00, any ρ3∞ ∈ [0.00,1.00]} readily conserve energy, linear momentum and angular momentum. Although the displacement and velocity are independent of ρ3∞, it is shown and proved that different choices of ρ3∞ gives different values of acceleration at every time step, thus yielding a different algorithm within the family. Nevertheless, in the sense of LMS methods, the entire family results in energy and momentum conserving algorithms regardless of the selection of ρ3∞ since only displacement and velocity participate in the algorithm as clearly presented in this paper. Numerious numerical illustration are presented to demonstrate the fundamental principles.

AB - A novel approach termed as the hybrid displacement-strain based normalized time weighted residual approach is presented in this exposition to accurately solve nonlinear structural dynamic problems. The current work concentrates on the design of a family of conserving time operators which preserve energy, linear and angular momentum conservation properties via this new innovative approach to solve nonlinear dynamic problems. The focus of this work is on Generalized Single Step Single Solve (GSSSS) computational algorithms which encompass the entire framework of those termed as linear multi-step (LMS) methods with unconditional stability and second-order accuracy which are most commonly used for such applications. In general, there exist three roots for LMS based methods, namely, the two principal roots ρ1∞, ρ2∞, and the spurious root ρ3∞. The LMS framework is comprised of two distinct algorithmic structures termed as constrained U and V algorithms. Specifically, it is shown that in the sense of LMS methods, the implementation of V0 algorithms (zero oder velocity overshoot behavior) via the hybrid displacement-strain based normalized weighted residual approach (no external constraints on energy are imposed) with ({ρ1∞, ρ2∞, ρ3∞} = {1.00,1.00, any ρ3∞ ∈ [0.00,1.00]} readily conserve energy, linear momentum and angular momentum. Although the displacement and velocity are independent of ρ3∞, it is shown and proved that different choices of ρ3∞ gives different values of acceleration at every time step, thus yielding a different algorithm within the family. Nevertheless, in the sense of LMS methods, the entire family results in energy and momentum conserving algorithms regardless of the selection of ρ3∞ since only displacement and velocity participate in the algorithm as clearly presented in this paper. Numerious numerical illustration are presented to demonstrate the fundamental principles.

UR - http://www.scopus.com/inward/record.url?scp=77957791618&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77957791618&partnerID=8YFLogxK

M3 - Conference article

JO - Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference

JF - Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference

SN - 0273-4508

ER -