TY - JOUR
T1 - Free vibration and divergence instability of pipes conveying fluid with uncertain structural parameters
TT - ارتعاشات آزاد و ناپایداری دیورژانس لولههای حامل سیال با پارامترهای سازهای نامعین
JF - mdrsjrns
JO - mdrsjrns
VL - 15
IS - 4
UR - http://mme.modares.ac.ir/article-15-4441-en.html
Y1 - 2015
SP - 247
EP - 254
KW - random vibration
KW - Random fields
KW - Monte Carlo simulation
KW - Fluid-Structure Interaction
KW - Stochastic stability analysis
N2 - In this article, Monte Carlo simulation method is used in conjunction with finite elements (FEs) for probabilistic free vibration and stability analysis of pipes conveying fluid. For fluid-structure interaction, Euler-Bernoulli beam model is used for analyzing pipe structure and plug flow model for representing internal fluid flow in the pipe. By considering structural parameters of system as random fields, the governing deterministic partial differential equation (PDE) of continuous system is transformed into a stochastic PDE. The continuous random fields are discretized by mid-point and local average discretization methods; then, by Monte Carlo simulations in each iteration loop, every distributed-parameter PDE having stochastic lumped-parameters is transformed into a deterministic distributed-parameter PDE. Each PDE is transformed into a system of deterministic ordinary differential equations (ODEs) by using FEs. Accordingly, all of the deterministic and stochastic parameters of system are discretized. For free vibration analysis, the eigenvalue problem is solved for investigating the complex-valued eigenvalues and critical eigenfrequencies. Consequently, having complex eigenfrequencies and divergence points, the statistical responses of stochastic problem are obtained like expected values, standard deviations, probability density functions, and the probability of occurrence for divergence instabilities.
M3
ER -