Numerical Calculations of the GRP Scheme for Nonconservative Ideal Fluid Mechanics Equations Relying on Parallel Calculation of Multifluid Grids

In order to solve the numerical method of nonconservative ideal hydrodynamics equations, the viscous perturbation technique for solving nonconservative hydrodynamics equations is improved and tested by solving the Riemann problem. The calculation of nonconservative ideal fluid mechanics is based on the GRP format. This article aims at the calculation method of nonconservative ideal fluid mechanics in the GRP format. Riemann and the corresponding periodic vortex are processed. The multifluid network processing method in the article is compared with the current method. The result can prove that this format can be used to solve the nonconservative ideal fluid dynamics equation of multiple values in the GRP format group, its computing power is strong, and the result of the solution is accurate.

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Special Issue on “CFD Based Researches and Applications for Fluid Machinery and Fluid Device”

Processes ◽

10.3390/pr9071137 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1137

Author(s):

Jin-Hyuk Kim ◽

Sung-Min Kim ◽

Minsuk Choi ◽

Lei Tan ◽

Bin Huang ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Power System ◽

Special Issue ◽

Numerical Techniques ◽

Fluid Machinery ◽

Computing Power ◽

Computational Fluid Dynamics Cfd

The demand for computational fluid dynamics (CFD)-based numerical techniques is increasing rapidly with the development of the computing power system [...]

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Energy–Vorticity Theory of Ideal Fluid Mechanics

Journal of the Atmospheric Sciences ◽

10.1175/2008jas2897.1 ◽

2009 ◽

Vol 66 (7) ◽

pp. 2073-2084 ◽

Cited By ~ 19

Author(s):

Peter Névir ◽

Matthias Sommer

Keyword(s):

Fluid Mechanics ◽

Shallow Water ◽

Ideal Fluid ◽

Characteristic Property ◽

Incompressible Flows ◽

Climate Simulations ◽

Shallow Water Models ◽

Complete Analogy ◽

Potential Enstrophy

Abstract Nambu field theory, originated by Névir and Blender for incompressible flows, is generalized to establish a unified energy–vorticity theory of ideal fluid mechanics. Using this approach, the degeneracy of the corresponding noncanonical Poisson bracket—a characteristic property of Hamiltonian fluid mechanics—can be replaced by a nondegenerate bracket. An energy–vorticity representation of the quasigeostrophic theory and of multilayer shallow-water models is given, highlighting the fact that potential enstrophy is just as important as energy. The energy–vorticity representation of the hydrostatic adiabatic system on isentropic surfaces can be written in complete analogy to the shallow-water equations using vorticity, divergence, and pseudodensity as prognostic variables. Furthermore, it is shown that the Eulerian equation of motion, the continuity equation, and the first law of thermodynamics, which describe the nonlinear evolution of a 3D compressible, adiabatic, and nonhydrostatic fluid, can be written in Nambu representation. Here, trilinear energy–helicity, energy–mass, and energy–entropy brackets are introduced. In this model the global conservation of Ertel’s potential enstrophy can be interpreted as a super-Casimir functional in phase space. In conclusion, it is argued that on the basis of the energy–vorticity theory of ideal fluid mechanics, new numerical schemes can be constructed, which might be of importance for modeling coherent structures in long-term integrations and climate simulations.

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Particle-Laden Turbulence: Progress and Perspectives

Annual Review of Fluid Mechanics ◽

10.1146/annurev-fluid-030121-021103 ◽

2021 ◽

Vol 54 (1) ◽

Author(s):

Luca Brandt ◽

Filippo Coletti

Keyword(s):

Fluid Dynamics ◽

Fluid Mechanics ◽

Online Publication ◽

Granular Media ◽

Finite Size ◽

Spherical Particles ◽

Annual Review ◽

Publication Date ◽

Zero Gravity ◽

Inertial Particles

This review is motivated by the fast progress in our understanding of the physics of particle-laden turbulence in the last decade, partly due to the tremendous advances of measurement and simulation capabilities. The focus is on spherical particles in homogeneous and canonical wall-bounded flows. The analysis of recent data indicates that conclusions drawn in zero gravity should not be extrapolated outside of this condition, and that the particle response time alone cannot completely define the dynamics of finite-size particles. Several breakthroughs have been reported, mostly separately, on the dynamics and turbulence modifications of small inertial particles in dilute conditions and of large weakly buoyant spheres. Measurements at higher concentrations, simulations fully resolving smaller particles, and theoretical tools accounting for both phases are needed to bridge this gap and allow for the exploration of the fluid dynamics of suspensions, from laminar rheology and granular media to particulate turbulence. Expected final online publication date for the Annual Review of Fluid Mechanics, Volume 54 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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Dispersed Fluid and Ideal Fluid Mechanics

Mathematical Concepts for Mechanical Engineering Design ◽

10.1201/b16339-7 ◽

2016 ◽

pp. 51-92

Keyword(s):

Fluid Mechanics ◽

Ideal Fluid

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Estimation of Super High-Rise Pumping Pressure for High-Performance Concrete Based on Computational Fluid Dynamics Modeling and Situation Measurement

Advances in Civil Engineering ◽

10.1155/2021/6446233 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Weijiu Cui ◽

Chuankai Zhao ◽

Sheng Wang

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Calculation Method ◽

Pressure Loss ◽

High Performance ◽

High Performance Concrete ◽

Accurate Method ◽

Dynamics Modeling ◽

High Rise ◽

Pipe Line

Traditional methods fail to predict the pumping pressure loss of high-performance concrete properly in super high-rise pumping situations due to complex changes of concrete properties. Therefore, it is imperative to propose a relative accurate method for pumping pressure estimation in super high-rise buildings. This paper builds the simplified pressure calculation method “pressure induced by the gravity plus pressure along the pipe line.” The later one is gained by establishing topology optimized model based on computational fluid dynamics and considering the lubrication layer formation. The effect of rheological properties and flow rate is analyzed based on this model in detail. Furthermore, the developed calculation method is verified by the measured pumping pressure during the super high-rise building construction of the Shanghai Tower (the tallest building in China recently). The relative differences between the calculation results and the measured data in situ are less than 6%, indicating the applicability of this method for predicting the pressure loss of the super high-rise pumping.

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Energy-Vorticity Theory of Ideal Fluid Mechanics

Journal of the Atmospheric Sciences ◽

10.1175/2009jas2897.1 ◽

2009 ◽

pp. 100802084958071

Author(s):

Peter Névir ◽

Matthias Sommer

Keyword(s):

Fluid Mechanics ◽

Ideal Fluid

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A research on the calculation method of car proportion based on image processing

MATEC Web of Conferences ◽

10.1051/matecconf/201816901006 ◽

2018 ◽

Vol 169 ◽

pp. 01006

Author(s):

Hong-Wei Xiao ◽

Chang-Jiang Jiang ◽

Jia-Xing Zhai ◽

Jing-Wei Chen

Keyword(s):

Image Processing ◽

Calculation Method ◽

Processing Method ◽

European American ◽

Projected Area ◽

Computer Image Processing ◽

New Thinking ◽

Length Width ◽

Line Relationship ◽

Total Average

The proportion of the car is one of the important parts of car styling design. The study of the car proportion is of great significance. The proportion of the car is determined by the technical conditions, functions and aesthetics. At present, there're not many studies on the area proportion of the car .There're studies on the line relationship and length, width, height proportion of the car. This paper uses computer image processing method to calculate the projected area proportion of the hatchback car. And it provides a new thinking and method for the car proportion study. The result shows that the projected area proportion values of the hatchback cars of European, American, Japanese, Korean and Chinese series on the market have a difference, but are close. And the total average projected area proportion values of car window and car body of the hatchbacks have been calculated.

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Structural analysis for in-service gas pipeline lowering using numerical method

MATEC Web of Conferences ◽

10.1051/matecconf/201815901058 ◽

2018 ◽

Vol 159 ◽

pp. 01058

Author(s):

Mochamad Safarudin ◽

Joga Dharma Setiawan

Keyword(s):

Structural Analysis ◽

Numerical Method ◽

Calculation Method ◽

Gas Pipeline ◽

Cost Benefits ◽

Pipeline Section ◽

The Cost

Construction of new highways, buildings, airport runways and other facilities is often planned at locations where aboveground pipelines are present. Relocating such lines can be extremely expensive in terms of shutdown time and new pipeline materials. Lowering this existing pipeline can have big cost benefits. The line can be lowered while remaining in service with no lost production and the cost of such lowering an existing pipeline section is relatively cheap. In this paper, the calculation method with both analytically and numerically are discussed and explained in a 28 in pipeline lowering process while keep the pipeline is safe and still in-service.

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