by National Aeronautics and Space Administration, Langley Research Center, Available from NASA Center for AeroSpace Information (CASI) in Hampton, Va, Hanover, MD .
Written in English
|Statement||Stephen A. Rizzi and Alexander A. Muravyov.|
|Series||[NASA technical memorandum] -- NASA/TM-2001-210838., NASA technical memorandum -- 210838.|
|Contributions||Muravyov, Alexander A., Langley Research Center.|
|The Physical Object|
March NASA/TM Improved Equivalent Linearization Implementations Using Nonlinear Stiffness Evaluation Stephen A. Rizzi and Alexander A. Muravyov. Improved equivalent linearization implementations using nonlinear stiffness evaluation (OCoLC) Online version: Rizzi, Stephen A. (Stephen Anthony). Improved equivalent linearization implementations using nonlinear stiffness evaluation (OCoLC) Material Type: Government publication, National government publication, Internet resource. The implementations are given the acronym ELSTEP, for Equivalent Linearization using a STiffness Evaluation Procedure. Both implementations of ELSTEP are fundamentally the same in that they use a novel nonlinear stiffness evaluation procedure to numerically compute otherwise inaccessible nonlinear stiffness terms from commercial finite element. Details of this implementation, together with the EL to follow, and collectively called ELSTEP for “Equivalent Linearization using a STiffness Evaluation Procedure,” are documented in. The stiffness evaluation entails first performing a normal modes analysis (solution ) to obtain the modal matrices, from which a subset of L modes are.
Improved Equivalent Linearization Implementations Using Nonlinear Stiffness Evaluation This report documents two new implementations of equivalent linearization for solving geometrically nonlinear random vibration problems of complicated structures. The implementations are given the acronym ELSTEP, for "Equivalent Linearization using a. For the EL methods using the concept of secant stiffness, the identical period ratio can be obtained except JPWRI method. This is because in this method the equivalent stiffness is determined using the effective design displacement (70%x d) rather than the maximum design displacement (x d), as shown in Eq.. As can be observed, the period. Improved Equivalent Linearization Implementations Using Nonlinear Stiffness Evaluation,” Report No. NASA/TM, L, NAS Equivalent Model Construction for a Non-Linear Dynamic System Based on an Element-Wise Stiffness Evaluation Procedure and Reduced Analysis of the Equivalent System,”. This paper investigates large amplitude multi-mode free vibration andrandom response of thin cylindrical panels of rectangular planform usinga finite element modal formulation. A thin laminated composite doublycurved element is developed. The system equation in structural nodal DOFis transformed into the modal coordinates by the using the modes of theunderlying linear system.
Equivalent Linearization Techniques Tttox•.xs K CAL-UnEX- Ual(h,rnia Instilhie of Technology, Pasadena, Cal(fornLt The method of equivalent linearization of Kryloff and Bogoliubov is generalized to the case of nonlinear dynamic systems with random excitation. The method is applied to a variety of problems, and the results. The use of stress predictions from equivalent linearization analyses in the computation of high-cycle fatigue life is examined. Stresses so obtained differ in behavior from the fully nonlinear. The concept of equivalent linearization of nonlinear system response as applied to direct displacement-based design is evaluated. Until now, Jacobsen's equivalent damping approach combined with the secant stiffness method has been adopted for the linearization . The primary goal of this project was the evaluation and improvement of the nonlinear static procedures (NSPs) of the research of Andrew Guyader on equivalent linearization and the NATO science fellowship from assembly of guidelines for the improved practical implementation of the procedures. Phase 3 consisted of.