Fatigue reliability assessment in time domain using stochastic-induced random stress loads due to limited experimental data

2020 ◽  
Vol 117 ◽  
pp. 104794
Author(s):  
S.S.K. Singh ◽  
S. Abdullah ◽  
A.K. Ariffin
2013 ◽  
Vol 470 ◽  
pp. 781-784 ◽  
Author(s):  
Chien Yi Huang ◽  
Yueh Hsun Lin ◽  
Eric Huang

A scientific approach is proposed in this research to investigate a disk on module (DOM) product's activation energy based on experimental data that eliminates subjective experience. This study considers multiple temperature conditions to enhance the accuracy of activation energy estimation. In order to ensure the consistency of failure mode in each temperature scenario, the slopes of Weibul probability plots obtained from the failure data are calculated followed by an examination for parallelism. The estimated life time under normal service condition differs from the results obtained using the industrial standard given activation energy by approximately 42%.


2021 ◽  
Vol 153 (A4) ◽  
Author(s):  
Y Garbatov ◽  
C Guedes Soares

This work deals with the fatigue reliability assessment of a welded joint in a longitudinal stiffener of trapezoidal shape in a very fast ferry. Based on the analysis of wave and cargo induced loads the ship hull structure is evaluated. The local structure is represented by a longitudinal stiffener with a trapezoidal transverse section. The critical hot-spots and the stress distributions are defined by FEM. The fatigue damage assessment of considered hot spots is analysed accounting for the combination of wave induced and car-breaking transient loadings. The formulation for the assessment of the welded steel joint is based on the S-N approach and FORM/SORM techniques are applied to evaluate the reliability against fatigue failure accounting for corrosion deterioration. The structural system composed by several hot spots is evaluated as a series system based on second order reliability bounds.


Author(s):  
Nobutaka Tsujiuchi ◽  
Yuichi Matsumura ◽  
Takayuki Koizumi

Abstract In this paper, we propose the new method to identify the Operating Deflection Shapes (ODSs) from the measurement data of time domain. At first, we present the identification scheme of ODSs based on a state-space model. Then the scheme is extended to identify the ODSs adaptively for the time-varying systems by using the URV Decomposition (URVD). Proposed scheme is able to decompose the deformation of a structure under operating condition into the underlying superposition of well excited frequency components. This paper introduces the algorithm and shows the effectiveness of our proposed scheme applyed for both synthesized and experimental data.


2001 ◽  
Vol 23 (10) ◽  
pp. 1203-1211 ◽  
Author(s):  
Sang-Hyo Kim ◽  
Sang-Woo Lee ◽  
Ho-Seong Mha

2020 ◽  
Vol 54 (2) ◽  
pp. 69-78
Author(s):  
Li-fen Hu ◽  
Hao Wu ◽  
Qingtao Gong ◽  
Xiangyang Wang ◽  
Wenbin Lv

AbstractUnderstanding of the complex dynamic behavior of damaged ships and floodwater remains limited for ship designers and safety authorities. In this work, a Navier-Stokes (NS) solver that combines the volume of fluid (VOF) method with overset mesh techniques is developed to simulate the flooding process of a damaged ship. The VOF method captures the fluid interface, and the turbulence effect on flows is considered with the k-ω model. The overset mesh techniques are employed to handle the mesh update following transient ship motions. Then, the results of a damaged barge with dynamic and overset mesh are compared with the experimental data. On the basis of this validation, the solver is applied to the flooding problems of a damaged warship. This research is intended to be a useful step toward the establishment of a stability criterion for damaged ships in the future.


2019 ◽  
Vol 09 (06) ◽  
pp. 1950046
Author(s):  
C. L. Wang

Two parameters are proposed as Jonscher indices, named after A. K. Jonscher for his pioneering contribution to the universal dielectric relaxation law. Time domain universal dielectric relaxation law is then obtained from the asymptotic behavior of dielectric response function and relaxation function by replacing parameters in Mittag–Leffler functions with Jonscher indices. Relaxation types can be easily determined from experimental data of discharge current in barium stannate titanate after their Jonscher indices are determined.


Sign in / Sign up

Export Citation Format

Share Document