SELECTION OF THE COMPUTATIONAL MODEL OF WIND FLOW IN THE PROBLEMS OF COMPUTATIONAL ARCHITECTURAL AND CIVIL ENGINEERING AERODYNAMICS IN ACCORDANSE WITH  REGULATORY AND TECHNICAL DOCUMENTS

An overview of the main directions of numerical simulation of problems of architectural and civil engineering aerodynamics based on Computational Fluid Dynamics (CFD) is presented. The main advantages of numerical simulation in comparison with traditional methods of aero-physical modeling in wind tunnels are highlighted. The basic principles of numerical simulation of wind loads and actions on buildings and structures are outlined. In modern practice, numerical modeling by finite volume method is used with the decomposition of the velocity of the turbulent wind flow into the average and pulsation component within the averaged by Reynolds solution of Navier-Stokes equations using the semi-empirical turbulence model k-ш SST. In practice, the problem of the legitimate (in accordance with the requirements of building codes) selection of a computational model of wind flow is very important. This is equivalent to the assignment of boundary conditions within numerical simulation. The computational model of the wind, presented in the Russian building codes, requires additions to solve the problems of numerical simulation of architectural and civil engineering aerodynamics. A detailed comparison of the computational models of wind flow in Russian and foreign building codes is carried out. The following wind flow parameters are analyzed: the profile of the average wind speed, the profile of the intensity of turbulence, the profile of the scale of turbulence. A table of correspondence of terrain types according to the classification of Russian and foreign codes is proposed. The possibility of determining the parameters of the computational wind flow model based on the joint use of building codes in force in Russia and Belarus is shown. A set of measures is proposed with the goal of creating a regulatory and technical environment for the practical application of computational architectural and civil engineering aerodynamics in real design.

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Analytical Computational Models for Relationship between Ultimate Bending Moment of Concrete Segments and Axial Force

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.853.177 ◽

2020 ◽

Vol 853 ◽

pp. 177-181

Author(s):

Zhi Yun Wang ◽

Shou Ju Li

Keyword(s):

Numerical Simulation ◽

Computational Model ◽

Axial Force ◽

Computational Models ◽

Plane Deformation ◽

Bending Moment ◽

Analytical Models ◽

Bending Moments ◽

Axial Forces ◽

Practical Engineering

Concrete segments are widely used to support soil and water loadings in shield-excavated tunnels. Concrete segments burden simultaneously to the loadings of bending moments and axial forces. Based on plane deformation assumption of material mechanics, in which plane section before bending remains plane after bending, ultimate bending moment model is proposed to compute ultimate bearing capacity of concrete segments. Ultimate bending moments of concrete segments computed by analytical models agree well with numerical simulation results by FEM. The accuracy of proposed analytical computational model for ultimate bending moment of concrete segments is numerically verified. The analytical computational model and numerical simulation for a practical engineering case indicate that the ultimate bending moment of concrete segments increases with increase of axial force on concrete segment in the case of large eccentricity compressive state.

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Numerical Simulation of Vortex Induced Vibration Using the K-ε Model

Volume 4: Terry Jones Pipeline Technology; Ocean Space Utilization; CFD and VIV Symposium ◽

10.1115/omae2006-92164 ◽

2006 ◽

Author(s):

Juan B. V. Wanderley ◽

Gisele H. B. Souza ◽

Carlos Levi

Keyword(s):

Numerical Simulation ◽

Stokes Equations ◽

Body Motion ◽

Navier Stokes ◽

Experimental Investigations ◽

Real Problem ◽

Navier Stokes Equations ◽

Vortex Induced Vibration ◽

Selection Of

Numerical simulations of Vortex Induced Vibration have been failing to duplicate accurately experimental data mostly due to the complexity of the physics involved in the real problem. Therefore, a careful and comprehensive investigation on CFD algorithms is still required to indicate the most suitable numerical scheme to handle such a complicate problem. Grid generation, boundary condition implementation, and coupling between the fluid flow governing equations and body motion equation are known to have strong influence on the qualities of the numerical results. This work presents results obtained from a long-term investigation featuring different CFD methods. The investigations enabled the selection of a very effective algorithm that showed an outstanding agreement between experiment and numerical simulation of the VIV phenomenon. Good agreement is obtained in the entire range of reduced velocity covered by the experimental investigations. The successful algorithm discussed here applies the Beam and Warming implicit scheme to solve the two-dimensional slightly compressible Navier–Stokes equations with the K-ε turbulence model to simulate the turbulent flow at the wake of the cylinder.

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Numerical Simulation on Computational Model of Hypersonic Slip Flow

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.563.241 ◽

2014 ◽

Vol 563 ◽

pp. 241-244

Author(s):

Xue Wei Liu ◽

Kai Luo ◽

Lei Ming ◽

Li Min Song ◽

Jun Jin

Keyword(s):

Numerical Simulation ◽

Mach Number ◽

Computational Model ◽

Knudsen Number ◽

Computational Models ◽

Slip Flow ◽

Slip Model

Three main computational models in hypersonic slip flow are derived and analyzed in detail and then compared by numerical simulation in which 2D cylinder hypersonic slip flow with Mach number 10 and Knudsen number 0.002, 0.01, 0.05, 0.25 are examined, results come out that the improved Maxwell slip model shows better applicability.

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INVESTIGATION HYPERBOLIC PARABOLOID SHELL IN THE WIND TUNNEL AND COMPARISON WITH NUMERICAL SIMULATIONS

Young Scientist ◽

10.32839/2304-5809/2018-12-64-58 ◽

2018 ◽

Vol 64 ◽

Author(s):

V.V. Stojanov ◽

S. Jgalli

Keyword(s):

Numerical Simulation ◽

Wind Tunnel ◽

Stokes Equations ◽

Navier Stokes ◽

Wind Flow ◽

Hyperbolic Paraboloid ◽

Ansys Fluent ◽

Navier Stokes Equations ◽

Basic Model ◽

The Impact

There are different ways to determine aerodynamic parameters, using analytical and experimental data for analyzing the behavior of structures when exposed to wind load. To date, the most developed is considered a numerical method for determining the characteristics of the above methods, based on the numerical solution of the Navier-Stokes equations. The accuracy of the results obtained using such a calculation method and obtaining the values of aerodynamic forces has increased due to the revision of mathematical models and the development of software complexes for the discretization of object bodies. This article gives an analytical overview of the results of research in the field of study the impact of wind loads on hypar (shell square in plan with the form of a hyperbolic paraboloid). The features of the investigated forms a discretization surface depending on pressure coefficients obtained in foreign literatures. Particular attention is paid to the numerical determination of aerodynamic coefficients on the surfaces of a hyperbolic paraboloid. The results were discussed and the nature of the distribution of coefficients depending on the angle of attack of the wind. Achieved analytical comparison computer modeling turbulent wind flows, based on solving the Reynolds equations arising from the use of averaging the Navier-Stokes equations. The basic model of turbulence such as: k-ε Standard Model; MMK; DBN; Shear-Stress Transport k-ω model; Transition k-kl-ω model. The possibility of choosing one or another model depending on the properties and characteristics of the wind flow is analyzed, for application in numerical simulation of wind flow around hyperbolic shells. The same was done, a comparative analysis of the results of physical testing in a wind tunnel with a numerical simulation in Ansys Fluent.

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ESTIMATION OF PEDESTRIAN COMFORT ON THE BASIS OF NUMERICAL MODELING OF WIND AERODYNAMICS OF BUILDINGS IN THE ENVIRONMENTAL DEVELOPMENT

International Journal for Computational Civil and Structural Engineering ◽

10.22337/2587-9618-2019-15-2-24-39 ◽

2019 ◽

Vol 15 (2) ◽

pp. 24-39

Author(s):

Alexander Belostotsky ◽

Irina Afanasyeva ◽

Irina Lantsova

Keyword(s):

Numerical Simulation ◽

Numerical Modeling ◽

Computational Model ◽

Flow Simulation ◽

Velocity Fields ◽

Numerical Results ◽

Green Spaces ◽

Wind Flow ◽

Environmental Development ◽

Under Construction

The distinctive paper is devoted to the methodology of pedestrian comfort estimation in the nearby area of the object under construction. A verification example of the wind flow simulation around and through a porous object is considered in order to select correct permeability parameters of the computational model of green spaces. The methodology of pedestrian comfort estimation is tested on the example of a real residential complex in Moscow. The results of the numerical simulation of velocity fields are used to calculate the criteria for pedestrian comfort specified in MDS 20-1.2006. Numerical results are obtained and compared for two study cases - without and with green spaces (bushes),to assess their impact on pedestrian comfort and the possibility of its adjustment.

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Numerical Simulation of Coal Suspension Sedimentation

Archives of Mining Sciences ◽

10.1515/amsc-2016-0005 ◽

2016 ◽

Vol 61 (1) ◽

pp. 59-68 ◽

Cited By ~ 1

Author(s):

Krzysztof Kołodziejczyk

Keyword(s):

Numerical Simulation ◽

Computational Model ◽

Laboratory Tests ◽

Purification Process ◽

High Concentration ◽

Grain Composition ◽

Ansys Fluent ◽

Coal Suspension ◽

Comparison Of The Results ◽

Selection Of

Abstract The article describes the feasibility of numerical simulation of sedimentation process of coal suspension, with high concentration, using the Ansys Fluent package, with the assumption monodisperse grain composition of the disperse phase of the suspension. The analysis contains selection of computational model, determine the parameters for analysis and comparison of the results with laboratory tests. To comparison laboratory measurement and numerical simulation sedimentation test was used. In the analysis was used suspension from the coal purification process.

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CSBPI_Site：Multi-Information Sources of Features to RNA Binding Sites Prediction

Current Bioinformatics ◽

10.2174/1574893615666210108093950 ◽

2021 ◽

Vol 15 ◽

Author(s):

Lichao Zhang ◽

Zihong Huang ◽

Liang Kong

Keyword(s):

Computational Model ◽

Binding Sites ◽

Noncoding Rna ◽

Computational Models ◽

Information Sources ◽

Rna Binding ◽

Rna Binding Proteins ◽

Gradient Boosting ◽

Position Information ◽

Rna Binding Sites

Background: RNA-binding proteins establish posttranscriptional gene regulation by coordinating the maturation, editing, transport, stability, and translation of cellular RNAs. The immunoprecipitation experiments could identify interaction between RNA and proteins, but they are limited due to the experimental environment and material. Therefore, it is essential to construct computational models to identify the function sites. Objective: Although some computational methods have been proposed to predict RNA binding sites, the accuracy could be further improved. Moreover, it is necessary to construct a dataset with more samples to design a reliable model. Here we present a computational model based on multi-information sources to identify RNA binding sites. Method: We construct an accurate computational model named CSBPI_Site, based on xtreme gradient boosting. The specifically designed 15-dimensional feature vector captures four types of information (chemical shift, chemical bond, chemical properties and position information). Results: The satisfied accuracy of 0.86 and AUC of 0.89 were obtained by leave-one-out cross validation. Meanwhile, the accuracies were slightly different (range from 0.83 to 0.85) among three classifiers algorithm, which showed the novel features are stable and fit to multiple classifiers. These results showed that the proposed method is effective and robust for noncoding RNA binding sites identification. Conclusion: Our method based on multi-information sources is effective to represent the binding sites information among ncRNAs. The satisfied prediction results of Diels-Alder riboz-yme based on CSBPI_Site indicates that our model is valuable to identify the function site.

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Numerical and Experimental Investigations on Vocal Fold Approximation in Healthy and Simulated Unilateral Vocal Fold Paralysis

Applied Sciences ◽

10.3390/app11041817 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1817

Author(s):

Zheng Li ◽

Azure Wilson ◽

Lea Sayce ◽

Amit Avhad ◽

Bernard Rousseau ◽

...

Keyword(s):

Computational Model ◽

Vocal Fold ◽

High Speed ◽

Computational Models ◽

Ex Vivo ◽

Vocal Fold Paralysis ◽

Future Application ◽

Experimental Investigations ◽

Type I ◽

Mri Scans

We have developed a novel surgical/computational model for the investigation of unilat-eral vocal fold paralysis (UVFP) which will be used to inform future in silico approaches to improve surgical outcomes in type I thyroplasty. Healthy phonation (HP) was achieved using cricothyroid suture approximation on both sides of the larynx to generate symmetrical vocal fold closure. Following high-speed videoendoscopy (HSV) capture, sutures on the right side of the larynx were removed, partially releasing tension unilaterally and generating asymmetric vocal fold closure characteristic of UVFP (sUVFP condition). HSV revealed symmetric vibration in HP, while in sUVFP the sutured side demonstrated a higher frequency (10–11%). For the computational model, ex vivo magnetic resonance imaging (MRI) scans were captured at three configurations: non-approximated (NA), HP, and sUVFP. A finite-element method (FEM) model was built, in which cartilage displacements from the MRI images were used to prescribe the adduction, and the vocal fold deformation was simulated before the eigenmode calculation. The results showed that the frequency comparison between the two sides was consistent with observations from HSV. This alignment between the surgical and computational models supports the future application of these methods for the investigation of treatment for UVFP.

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The Lamprey Forebrain – Evolutionary Implications

Brain Behavior and Evolution ◽

10.1159/000517492 ◽

2021 ◽

pp. 1-16

Author(s):

Shreyas M. Suryanarayana ◽

Juan Pérez-Fernández ◽

Brita Robertson ◽

Sten Grillner

Keyword(s):

Basal Ganglia ◽

Sensory Integration ◽

Critical Role ◽

Detailed Comparison ◽

Common Ancestry ◽

Dopamine System ◽

Cortical Areas ◽

Neural Processes ◽

Living Group ◽

Selection Of

The forebrain plays a critical role in a broad range of neural processes encompassing sensory integration and initiation/selection of behaviour. The forebrain functions through an interaction between different cortical areas, the thalamus, the basal ganglia with the dopamine system, and the habenulae. The ambition here is to compare the mammalian forebrain with that of the lamprey representing the oldest now living group of vertebrates, by a review of earlier studies. We show that the lamprey dorsal pallium has a motor, a somatosensory, and a visual area with retinotopic representation. The lamprey pallium was previously thought to be largely olfactory. There is also a detailed similarity between the lamprey and mammals with regard to other forebrain structures like the basal ganglia in which the general organisation, connectivity, transmitters and their receptors, neuropeptides, and expression of ion channels are virtually identical. These initially unexpected results allow for the possibility that many aspects of the basic design of the vertebrate forebrain had evolved before the lamprey diverged from the evolutionary line leading to mammals. Based on a detailed comparison between the mammalian forebrain and that of the lamprey and with due consideration of data from other vertebrate groups, we propose a compelling account of a pan-vertebrate schema for basic forebrain structures, suggesting a common ancestry of over half a billion years of vertebrate evolution.

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