Shannon Entropy-Based Wavelet Transform Method for Autonomous Coherent Structure Identification in Fluid Flow Field Data

The interaction between a fluid flow and a transversely isotropic porous medium is described. A homogenized model is used to treat the flow field in the porous region, and different interface conditions, needed to match solutions at the boundary between the pure fluid and the porous regions, are evaluated. Two problems in different flow regimes (laminar and turbulent) are considered to validate the system, which includes inertia in the leading-order equations for the permeability tensor through a Oseen approximation. The components of the permeability, which characterize microscopically the porous medium and determine the flow field at the macroscopic scale, are reasonably well estimated by the theory, both in the laminar and the turbulent case. This is demonstrated by comparing the model’s results to both experimental measurements and direct numerical simulations of the Navier–Stokes equations which resolve the flow also through the pores of the medium.

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Study of Segmentation Threshold Based on Wavelet Transform

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.3855 ◽

2013 ◽

Vol 756-759 ◽

pp. 3855-3859

Author(s):

Jian Yi Li ◽

Hui Juan Wang

Keyword(s):

Wavelet Transform ◽

Digital Image ◽

Region Growing ◽

Detection Methods ◽

Mathematical Tool ◽

Matlab Simulation ◽

Segmentation Method ◽

Transform Method ◽

Threshold Segmentation ◽

Digital Image Enhancement

Based on the research of the four kinds of algorithms of digital image segmentation, based on edge detection methods, based on region growing method, threshold segmentation method and digital image threshold segmentation method based on wavelet transform, using MATLAB simulation of all digital image enhancement and segmentation process, the obtained results are analyzed, proving the threshold segmentation wavelet transform method has unparalleled advantages in information extraction in medical image. Wavelet transform is a mathematical tool widely used in recent years, compared with the Fu Liye transform, the window of Fu Liye transform, wavelet transform is the local transform of space and frequency, it can be very effective in extracting information from the signal [[1.

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Fluid Flow Field in the Annulus of Boiling Water (BWR) Nuclear Reactors Under Normal and Accident Conditions

Volume 4: Fluid-Structure Interaction ◽

10.1115/pvp2009-77442 ◽

2009 ◽

Author(s):

Raju Ananth ◽

Karen Fujikawa ◽

Jay Gillis

Keyword(s):

Fluid Flow ◽

Velocity Field ◽

Flow Field ◽

Pressure Vessel ◽

Theoretical Study ◽

Nuclear Reactors ◽

Boiling Water ◽

Flow Conditions ◽

Accident Conditions ◽

Reactor Pressure

This paper presents a theoretical study of the velocity field in the annulus formed between the Reactor Pressure Vessel (RPV) and the shroud of a Boiling Water Reactor (BWR) under normal and accident flow conditions. Simplified geometry and an ideal irrotational flow are assumed to solve the problem using velocity potentials.

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Fluid flow phenomena in metals processing operations: Numerical description of the fluid flow field by an impinging gas jet on a liquid surface

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2019.105220 ◽

2020 ◽

Vol 165 ◽

pp. 105220 ◽

Cited By ~ 2

Author(s):

Rim Ben Kalifa ◽

Sonia Ben Hamza ◽

Nejla Mahjoub Saïd ◽

Hervé Bournot

Keyword(s):

Fluid Flow ◽

Flow Field ◽

Liquid Surface ◽

Gas Jet ◽

Flow Phenomena ◽

Metals Processing

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Grinding Fluid Flow Field Modeling and Multi-Parameter Numerical Analysis Based on Smooth Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.156-157.948 ◽

2010 ◽

Vol 156-157 ◽

pp. 948-955

Author(s):

Guang Yao Meng ◽

Ji Wen Tan ◽

Yi Cui

Keyword(s):

Fluid Flow ◽

Numerical Analysis ◽

Flow Field ◽

Dynamic Pressure ◽

Grinding Wheel ◽

Lubricating Film ◽

Fluid Field ◽

Grinding Fluid ◽

Smooth Model ◽

Area Increase

Relative motion between grinding wheel and workpiece makes the lubricant film pressure formed by grinding fluid in the grinding area increase, consequently, dynamic pressure lubrication forms. The grinding fluid flow field mathematical model in smooth grinding area is established based on lubrication theory. The dynamic pressure of grinding fluid field, flow velocity and carrying capacity of lubricating film are calculated by the numerical analysis method. An analysis of effect of grinding fluid hydrodynamic on the total lifting force is performed, and the results are obtained.

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