The increasing demand for dynamic analysis of large-scale structural systems has highlighted the need efficient model reduction methods. Reduced order modeling allows large finite element models to be represented with significantly fewer degrees freedom while retaining essential characteristics. This paper investigates Enhanced Craig–Bampton (ECB) method and further explores its application in analysis. effectiveness ECB is evaluated by comparing it conventional (CB) full using benchmark...

Summary In this paper, we develop a robust reduced‐order modeling method, named algebraic dynamic condensation, which is based on the improved reduced system method. Using substructuring, global mass and stiffness matrices are divided into many small submatrices without considering physical domain, substructures interface boundary defined in perspective. The model then constructed using three additional procedures: substructural reduction, inertial effect condensation. formulation of simply...

Summary In this study, we propose an effective method to estimate the reliability of finite element models reduced by automated multi‐level substructuring (AMLS) method. The proposed error estimation can accurately predict relative eigenvalue errors in models. A new, enhanced transformation matrix for AMLS is derived from original properly considering contribution residual substructural modes. important prerequisite develop Adopting basic concept recently developed Craig–Bampton method,...

Abstract In this paper, to evaluate the residual stress of welded structures efficiently, we propose a welding simulation method utilizing reduced order model. To construct model, finite element model is divided into target part and an omitted part. For heat transfer analysis, thermal boundary condition newly defined applied part, compensate for loss induced by neglecting elastic plastic constructed using automated static condensation method. The performance proposed adopting verified...

Owing to the increasing size and speed of ships ensure economic efficiency, hydroelastic phenomena hull have emerged as an important factor be considered in evaluation strength during design stage current ship building procedures. In this study, we established a method evaluate fatigue with linear spring effects using 1D (one-dimensional) beam model 3D (three-dimensional) global Finite Element (FE) model. Firstly, FSI (fluid–structure interaction) analysis was carried out 15,000 twenty...

In this paper, we introduce an efficient new model reduction method, named the automated static condensation which is developed for local analysis of large finite element models. The algebraic multilevel substructuring procedure modified appropriately, and then applied to original method. retained substructure, be analyzed, defined, remaining part global automatically partitioned into many omitted substructures in perspective. For procedure, a substructural tree diagram sets are established....

In this paper, the accuracy of Craig–Bampton method, one most widely used component mode synthesis methods, is improved. Considering higher-order effect residual modes that are simply truncated in original finite element model can be more accurately reduced. formulation, unknown eigenvalues considered as additional generalized coordinates, which eliminated by employing concept system equivalent reduction expansion process. The new named method. formulation method presented, and its improved...

In this study, we propose effective formulations for modal, frequency response, and transient analyses using condensed matrices of the finite element (FE) model. Employing iterated improved reduced system (IIRS) method, a transformation matrix is defined that condenses stiffness inertial effects nodes to be neglected into interest. Using this, mass are derived. With these two matrices, damping derived Rayleigh damping. By considering in original structural dynamic formulation based on global...

In this paper, we introduce a new method for assembly of shipbuilding blocks at sea and present its feasibility focusing on structural safety. The core concept is to assemble ship building by use bolting, gluing welding techniques without dock facilities. Due independence facilities, shipyard construction capability could be increased considerably the proposed method. To show safety method, bulk carrier an oil tanker were employed, investigated behavior those ships which block was applied....

To detect and prevent structural damage caused by various loads on marine structures ships, health monitoring procedure is essential. Estimating acting the which are measured sensors that mounted properly crucial for monitoring. However, attaching an excessive number of to structure without consideration can be inefficient due high costs involved potential inducing instability. In this study, we introduce a method determine optimal their optimized locations strain measurement sensors,...

Abstract In this manuscript, we propose a new effective method for eigenpair reanalysis of large-scale finite element (FE) models. Our utilizes the matrix block-partitioning algorithm in Rayleigh–Ritz approach and expresses Ritz basis using thousands block matrices very small size. To avoid significant computational costs from projection procedure, derive formulation that uses tiny computations instead global computations. Additionally, present an recognizes which blocks are changed modified...

A cost effective finite element (FE) procedure is proposed for analysis of load-carrying structures with nonlinear contact and frictional behaviors between large floating offshore structures. The key the to use static condensation technique developed from Guyan model reduction method. time computing friction forces on interface areas can be dramatically reduced compared a full FE model. Two representative applications projects are presented. One problem independent tank support in FLNG hull...

In this paper, a new efficient method for structural modal reanalysis is proposed, which can handle large finite element (FE) models requiring frequent design modifications. The global FE model divided into residual part not to be modified and target modified. Then, an automated matrix permutation substructuring algorithm applied these parts independently. reduced the calculated saved in initial analysis, repeatedly, whenever modifications occur. assembled with that of already saved; thus,...