Frequency response function (FRF) based updating of a laser spot welded structure

The objective of this paper is to present frequency response function (FRF) based updating as a method for matching the finite element (FE) model of a laser spot welded structure with a physical test structure. The FE model of the welded structure was developed using CQUAD4 and CWELD element connectors, and NASTRAN was used to calculate the natural frequencies, mode shapes and FRF. Minimization of the discrepancies between the finite element and experimental FRFs was carried out using the exceptional numerical capability of NASTRAN Sol 200. The experimental work was performed under free-free boundary conditions using LMS SCADAS. Avast improvement in the finite element FRF was achieved using the frequency response function (FRF) based updating with two different objective functions proposed.

[1]  Salmiah Kasolang,et al.  Finite element modelling and modal based updating for the dynamic behaviour of a laser spot welded structure , 2016 .

[2]  Michael Link,et al.  UPDATING ANALYTICAL MODELS BY USING LOCAL AND GLOBAL PARAMETERS AND RELAXED OPTIMISATION REQUIREMENTS , 1998 .

[3]  Mehmet Imregun,et al.  Finite element model updating using frequency response function data: I. Theory and initial investigation , 1995 .

[4]  Xiaocong He,et al.  Finite Element Analysis of Laser Welding: A State of Art Review , 2012 .

[5]  Muhamad Abdul Rani,et al.  Structural dynamic analysis and model updating for a welded structure made from thin steel sheets , 2011 .

[6]  Xinglin Guo,et al.  A new frequency matching technique for FRF-based model updating , 2017 .

[7]  John E. Mottershead,et al.  Finite Element Model Updating in Structural Dynamics , 1995 .

[8]  John E. Mottershead,et al.  SELECTION AND UPDATING OF PARAMETERS FOR AN ALUMINIUM SPACE-FRAME MODEL , 2000 .

[9]  Linda Simo Mthembu,et al.  FINITE ELEMENT MODEL UPDATING , 2013 .

[10]  John E. Mottershead,et al.  The sensitivity method in finite element model updating: A tutorial (vol 25, pg 2275, 2010) , 2011 .

[11]  John E. Mottershead,et al.  Model Updating In Structural Dynamics: A Survey , 1993 .

[12]  Wei-Xin Ren,et al.  Finite element model updating in structural dynamics by using the response surface method , 2010 .

[13]  John E. Mottershead,et al.  Experimental and theoretical studies of a bolted joint excited by a torsional dynamic load , 2006 .