Orthogonal Expansion Method of Random Processes for Fluctuating Pressure of Water Flow

Abstract:

Combining with its auto-correlation function, the stochastic process of water flows fluctuating pressure is decomposed on the trigonometric bases by employing an expansion method based on normalized orthogonal bases which is prescribed, and thus establish an incentive model for the random dynamic response analysis of structures vibrated by water flows fluctuating pressure. By using the model, main probabilistic characters of the flows stochastic process are captured with only a few random variables, and therefore laid the foundation for further random response and reliability analysis from the point of probability density evolution. By using it in an instance, the validity of the model is tested from the aspect of second order statistics such as sampling ensemble power spectrum and sample mean square error. The effects of simulation duration and expansion numbers needed on the simulations efficiency and accuracy are also discussed.

• Periodical: Applied Mechanics and Materials (Volume 459)
• Pages: 619-624
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.459.619
• Online since: October 2013
• Authors: En Li Ye*, Yi Hong Zhou
• Keywords: Auto-Correlation Function, Fluctuating Pressure of Water Flow, Normalized Orthogonal Bases, Orthogonal Expansion, Stochastic Processes

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