This document summarizes a study that used Reynolds-Averaged Navier-Stokes (RANS) turbulence models to simulate wind pressures on a target low-rise building immersed in groups with various area densities. Wind tunnel tests were conducted for comparison. The results showed that the RNG k-ε model provided more reasonable wind pressure coefficients for an isolated model, but different turbulence models produced similar results for a target model in a large group. Additionally, varying the incident wind flow had little effect on wind pressure coefficients, while area density and proximity of upstream buildings had a larger influence.
Effect of Wind Direction through Double Storied Building Model Configurations...inventionjournals
: Effect of wind direction on plume dispersion around urban buildings has been investigated by physical modelling using arrays of buildings- like obstacles at scale 1:100 in boundary layer wind tunnel for double storied buildings and compared with field data. The particular effect of obstacle width- to - height ratio (S/H) was examined for a fixed obstacle plan area density. Series of experiments have been carried out in which the wind direction varied in steps of 5 for selected orientation of line source at 900 , 95, 100 and 105. Further, from the observation, it was concluded that the maximum lateral concentration shift to upward the wind direction of line source is increased for inline double storied buildings model configuration. It can be concluded, the wind tunnel results showed that concentrations at downwind distances decreased as the wind direction increases (positive values) for measured orientation of line source in inline double storied buildings model configuration. In comparison, experimentally observed σz values are below the field values. They were best fitted with power-law profiles. The non-dimensional concentration for both the field and wind tunnel results of double storied inline buildings configuration seems to be more or less uniform. Values of vertical spread parameters for double storied inline array configuration and field data were followed a similar trend but inline array configuration of double storied buildings model, non-dimensional concentrations were typically twice larger compared to the field data. This is attributed to the fact that the tracer material is quite concentrated in the recirculation region in inline array configuration of the double storied buildings model.
Effect of Wind Direction through Single Storied Building Model Configurations...inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
The Journal will bring together leading researchers, engineers and scientists in the domain of interest from around the world. Topics of interest for submission include, but are not limited to:
45 investigation paper id 0008 edit septianIAESIJEECS
Most numerical studies on flow over buildings simplify the geometry of the roof and assume that it is flat. This may lead to misrepresentation of the flow as the roof of actual buildings contains some sort of roughness. In this study, the flow over the administrative building of Universiti Tenaga Nasional is investigated for multidirectional flow conditions. The actual topology of the building is gridded and simulated using the steady-state Reynolds-averaged Navier-Stokes equation. Four points at the top of the building are identified and the wind statistics at these designated locations at three different heights are investigated. The optimal location with the highest average wind speed and consistent wind speeds for all wind angles is identified and is earmarked as a potential location to install the wind turbine.
The document summarizes a numerical study that investigated the effect of distributed trailing edge suction on the aerodynamic performance of a wind turbine airfoil. Computational fluid dynamics simulations were performed on a NACA 63-415 airfoil with and without trailing edge suction at different angles of attack. The results showed that moderate levels of suction (0.5 m/s) improved the airfoil's lift-to-drag ratio by increasing maximum lift and reducing drag. Higher suction velocities (over 1 m/s) decreased aerodynamic performance by increasing drag. The optimum angle of attack was also increased from 4 degrees to 6 degrees with suction. Streamline visualizations indicated that suction effectively removed boundary layer flow
technoloTwo dimensional numerical simulation of the combined heat transfer in...ijmech
A numerical investigation was conducted to analyze the flow field and heat transfer characteristics in a vertical channel withradiation and blowing from the wall. Hydrodynamic behaviour and heat transfer results are obtained by the solution of the complete Navier–Stokesand energy equations using a control volume finite element method. Turbulent flow with "Low Reynolds Spalart-Allmaras Turbulence Model" and radiation with "Discrete Transfer Radiation Method" had been modeled. In order to have a complete survey, this article has a wide range of study in different domains including velocity profiles at different locations, turbulent viscosity, shear stress, suctioned mass flow rate in different magnitude of the input
Rayleigh number, blowing Reynoldsnumber, radiation parameter, Prandtl number, the ratio of length to width and also ratio of opening thickness to width of the channel. In addition, effects of variation in any of the above non-dimensional numbers on parameters of the flow are clearly illustrated. At the end resultants had been compared with experimental data which demonstrated that in the present study, results have a great accuracy, relative errors are very small and the curve portraits are in a great
agreement with real experiments.
Aerodynamic_loading_of_solar_trackers_on flat roofs - super super.pdfssuser99a391
This study uses wind tunnel experiments to investigate the aerodynamic loading of solar trackers installed on flat-roofed buildings. The experiments measured pressure distributions on a model solar tracker under varying wind directions, azimuth angles, inclination angles, and pedestal heights. The results show that the attack angle of wind is a key factor for wind loads on trackers. Loads increase with pedestal height and inclination angle, regardless of wind direction or azimuth angle. Maximum loads occur at 45° inclination and 0° or 180° attack angles due to separation shear layers. Sheltering by adjacent buildings reduces windward pressure and increases net pressure on downwind trackers spaced less than five times the building height.
IRJET- Numerical Study of Heat Transfer Characteristics on a Dimpled Surface ...IRJET Journal
This document summarizes previous research on using dimpled surfaces and pulsating jet impingement to improve heat transfer efficiency. It discusses how increasing the surface area through dimpling and optimizing frequency factors can increase heat transfer rates by up to 36%. Previous studies found that pulsating jets can enhance average heat transfer by 30-80% compared to steady jets, and that symmetrical jet pulsations without a phase difference marginally improve heat transfer while pulsations with a phase difference significantly enhance heat transfer around stagnation points. The document reviews various factors that influence heat transfer rates, such as Reynolds number, frequency, jet diameter, wall-to-nozzle spacing, and dimple geometry.
An Experimental Study on Vehicular Emission Dispersion through Single Storied...inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Effect of Wind Direction through Double Storied Building Model Configurations...inventionjournals
: Effect of wind direction on plume dispersion around urban buildings has been investigated by physical modelling using arrays of buildings- like obstacles at scale 1:100 in boundary layer wind tunnel for double storied buildings and compared with field data. The particular effect of obstacle width- to - height ratio (S/H) was examined for a fixed obstacle plan area density. Series of experiments have been carried out in which the wind direction varied in steps of 5 for selected orientation of line source at 900 , 95, 100 and 105. Further, from the observation, it was concluded that the maximum lateral concentration shift to upward the wind direction of line source is increased for inline double storied buildings model configuration. It can be concluded, the wind tunnel results showed that concentrations at downwind distances decreased as the wind direction increases (positive values) for measured orientation of line source in inline double storied buildings model configuration. In comparison, experimentally observed σz values are below the field values. They were best fitted with power-law profiles. The non-dimensional concentration for both the field and wind tunnel results of double storied inline buildings configuration seems to be more or less uniform. Values of vertical spread parameters for double storied inline array configuration and field data were followed a similar trend but inline array configuration of double storied buildings model, non-dimensional concentrations were typically twice larger compared to the field data. This is attributed to the fact that the tracer material is quite concentrated in the recirculation region in inline array configuration of the double storied buildings model.
Effect of Wind Direction through Single Storied Building Model Configurations...inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
The Journal will bring together leading researchers, engineers and scientists in the domain of interest from around the world. Topics of interest for submission include, but are not limited to:
45 investigation paper id 0008 edit septianIAESIJEECS
Most numerical studies on flow over buildings simplify the geometry of the roof and assume that it is flat. This may lead to misrepresentation of the flow as the roof of actual buildings contains some sort of roughness. In this study, the flow over the administrative building of Universiti Tenaga Nasional is investigated for multidirectional flow conditions. The actual topology of the building is gridded and simulated using the steady-state Reynolds-averaged Navier-Stokes equation. Four points at the top of the building are identified and the wind statistics at these designated locations at three different heights are investigated. The optimal location with the highest average wind speed and consistent wind speeds for all wind angles is identified and is earmarked as a potential location to install the wind turbine.
The document summarizes a numerical study that investigated the effect of distributed trailing edge suction on the aerodynamic performance of a wind turbine airfoil. Computational fluid dynamics simulations were performed on a NACA 63-415 airfoil with and without trailing edge suction at different angles of attack. The results showed that moderate levels of suction (0.5 m/s) improved the airfoil's lift-to-drag ratio by increasing maximum lift and reducing drag. Higher suction velocities (over 1 m/s) decreased aerodynamic performance by increasing drag. The optimum angle of attack was also increased from 4 degrees to 6 degrees with suction. Streamline visualizations indicated that suction effectively removed boundary layer flow
technoloTwo dimensional numerical simulation of the combined heat transfer in...ijmech
A numerical investigation was conducted to analyze the flow field and heat transfer characteristics in a vertical channel withradiation and blowing from the wall. Hydrodynamic behaviour and heat transfer results are obtained by the solution of the complete Navier–Stokesand energy equations using a control volume finite element method. Turbulent flow with "Low Reynolds Spalart-Allmaras Turbulence Model" and radiation with "Discrete Transfer Radiation Method" had been modeled. In order to have a complete survey, this article has a wide range of study in different domains including velocity profiles at different locations, turbulent viscosity, shear stress, suctioned mass flow rate in different magnitude of the input
Rayleigh number, blowing Reynoldsnumber, radiation parameter, Prandtl number, the ratio of length to width and also ratio of opening thickness to width of the channel. In addition, effects of variation in any of the above non-dimensional numbers on parameters of the flow are clearly illustrated. At the end resultants had been compared with experimental data which demonstrated that in the present study, results have a great accuracy, relative errors are very small and the curve portraits are in a great
agreement with real experiments.
Aerodynamic_loading_of_solar_trackers_on flat roofs - super super.pdfssuser99a391
This study uses wind tunnel experiments to investigate the aerodynamic loading of solar trackers installed on flat-roofed buildings. The experiments measured pressure distributions on a model solar tracker under varying wind directions, azimuth angles, inclination angles, and pedestal heights. The results show that the attack angle of wind is a key factor for wind loads on trackers. Loads increase with pedestal height and inclination angle, regardless of wind direction or azimuth angle. Maximum loads occur at 45° inclination and 0° or 180° attack angles due to separation shear layers. Sheltering by adjacent buildings reduces windward pressure and increases net pressure on downwind trackers spaced less than five times the building height.
IRJET- Numerical Study of Heat Transfer Characteristics on a Dimpled Surface ...IRJET Journal
This document summarizes previous research on using dimpled surfaces and pulsating jet impingement to improve heat transfer efficiency. It discusses how increasing the surface area through dimpling and optimizing frequency factors can increase heat transfer rates by up to 36%. Previous studies found that pulsating jets can enhance average heat transfer by 30-80% compared to steady jets, and that symmetrical jet pulsations without a phase difference marginally improve heat transfer while pulsations with a phase difference significantly enhance heat transfer around stagnation points. The document reviews various factors that influence heat transfer rates, such as Reynolds number, frequency, jet diameter, wall-to-nozzle spacing, and dimple geometry.
An Experimental Study on Vehicular Emission Dispersion through Single Storied...inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Prediction of aerodynamic characteristics for slender bluff bodies with nose ...vasishta bhargava
This document discusses numerical simulations of aerodynamic characteristics for slender bluff bodies with different nose cone shapes. Four cylinder models were analyzed: a conical nose (A), and blunt nose cones with tip diameters of 0.1m (B), 0.08m (C), and 0.06m (D). A panel method was used to calculate lift, drag, and pressure distributions at angles of attack from -10 to 20 degrees and velocities from 5-25 m/s. Pressure peaked on the suction side of the conical nose at -10 and 10 degrees. Blunt nose cylinders B, C, and D showed similar pressure distributions, with peaks shifting location compared to the conical nose. Veloc
Analysis of Wind Load Factors and Stability on Sensitive StructuresIRJET Journal
The document analyzes wind loads and stability on sensitive structures with curved roofs through wind tunnel experiments and computational fluid dynamics simulations. Curved roof models with different rise-to-span and wall height-to-span ratios were tested under uniform, open terrain, and suburban terrain wind conditions for a range of wind angles. The results show that wall height significantly affects wind pressures on the roof, with higher walls producing lower pressures in the windward quarter and higher suctions in the center and leeward quarters. Open and suburban terrains produce more variable pressures than uniform flow. The study provides pressure coefficient data to help establish wind loading for structural design of curved roofs.
Numerical and experimental investigation of co shedding vortex generated by t...Alexander Decker
The document investigates the effect of co-shedding vortices generated by two adjacent circular cylinders on air flow behavior around an NACA 2412 airfoil. Both experimental and numerical methods were used. Experimentally, a smoke wind tunnel was used to visualize flow at different velocities and angles of attack. Numerically, ANSYS was used to simulate results. The study found that the vortices induced turbulence upstream of the airfoil, preventing separation and allowing reattachment of the flow. Both methods showed that increasing angle of attack or velocity shifted the separation point toward the leading edge. The vortices generated by the cylinders thus helped control flow separation around the airfoil.
This document provides an overview of existing dispersion models and literature on modeling the dispersion of emissions from rooftop stacks. It summarizes key findings from previous studies on how increasing stack height and exhaust velocity can reduce pollutant concentrations at nearby receptors. However, it notes that field studies have sometimes found concentrations to be higher than predicted by models, due to factors like nearby buildings and atmospheric turbulence. The document then describes the ASHRAE geometric design method and dilution models that will be evaluated using new field data collected for this study.
03302--ICWE14-2015-Experimental and Numerical Evaluation of Micrositing in Co...Jussara M. Leite Mattuella
This document summarizes experimental and numerical research evaluating the speed-up effect in complex terrain areas. Wind tunnel experiments and computational fluid dynamics (CFD) simulations were used to analyze wind speed and turbulence intensity profiles above symmetrical hill models with slopes of 25, 32, 52, and 68 degrees, representing complex terrain. Both methods found increased wind speeds at hill crests due to the speed-up effect. The research aims to compare the two methods for analyzing the speed-up factor and how increased wind speeds could enable wind energy development in complex areas.
Numerical Modelling of Wind Patterns around a Solar Parabolic Trough CollectorIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Calculation of Fluid Dynamic for Wind Flow around Reinforced Concrete WallsIJERA Editor
A study on the flow phenomena around free-standing walls is important in practical building construction. In the present paper a numerical study is conducted for two- dimensional incompressible steady flow around freestanding walls using low-Re k-co turbulence model. The separation regions downstream the wall and on the roof of the leeward were predicted. Finally, results of numerical simulation are presented in the form of velocity vectors, velocity contour, pressure contours and streamlines
Effect of mainstream air velocity on velocity profile over a rough flat surfaceijceronline
1) The document discusses an experiment that measured the velocity profile over a rough flat surface at different locations along the surface (sections) and with varying mainstream air velocities.
2) The results showed that at a given location, velocity increased with increasing mainstream velocity. Additionally, boundary layer thickness increased with distance from the leading edge but decreased with increasing mainstream velocity.
3) In conclusion, the velocity over the rough surface was significantly influenced by the incoming air velocity, and boundary layer thickness varied inversely with mainstream velocity but directly with distance from the leading edge.
Trailing edge noise prediction from NACA 0012 and NACA 6320 using empirical p...vasishta bhargava
Trailing edge of airfoil represents one of important sources in aerodynamic noise production. In this paper, the numerical computation of sound pressure using quasi empirical model and wall pressure spectrum models based on external pressure gradients was conducted for NACA 0012 and NACA 6320 airfoils. The development of boundary layer thickness and displacement thickness for different chord lengths and Mach numbers with varying angles of attack, are illustrated for NACA 0012. The sound pressure levels evaluated between 00 to 60angles of attack and at constant chord length of 1.2m using BPM model showed change of ~5dB in peak amplitude. The maximum test velocity and chord length used for analysis is 65 m/s and 1.5m. The relative velocities for airfoils have been computed using the boundary element and panel method. Boundary layer properties involving chord Reynolds number, 3.14 x106, 4.6 x106and Reynolds number based on wall shear, 7410, 6865 were assessed at 20 AOA for NACA 0012. Results have found higher values for thickness at increasing angle of attack but decayed along chord length. Comparison of wall pressure spectrum for favorable and adverse pressure gradients were done and validated with existing literature predictions
IRJET - Wind Analysis of High Rise BuildingsIRJET Journal
This document discusses wind analysis methods for high-rise buildings. It presents a FORTRAN program developed to perform random vibration analysis (RVA) to determine the structural response of buildings due to wind loads. RVA considers both the mean and fluctuating components of deflection. The document also discusses codal analysis methods which can determine wind loads, shear forces, and bending moments on structures. It applies both RVA and codal analysis to evaluate wind loads on sample high-rise buildings and chimneys. The results are then compared to published literature values.
This document summarizes a numerical study of airflow over an Ahmed body using RANS turbulence models. It finds that the k-ε-v2 model more accurately predicts separation and reattachment compared to other models. The study simulates flow over an Ahmed body with a 35 degree rear angle using various turbulence models and investigates the effects of grid layout and differencing schemes on the results. Numerical results agree well with experimental data on the wake structure and turbulent kinetic energy distribution behind the body.
This document summarizes revisions made to the gust effect factor formulation in ASCE7-95 wind load provisions. It discusses concepts of spatial and temporal wind averaging and introduces the new gust effect factor. The factor is derived based on considerations of peak gust wind speeds, turbulence intensity, structure size, and other factors. Examples are provided to illustrate using the new provisions to evaluate gust effect factors for flexible structures.
This document describes an experimental and computational study of flow over a blunt cylinder-flare model in high supersonic flow. Wind tunnel experiments were conducted in the TST-27 and ST-15 wind tunnels at Mach numbers from 3 to 4 and angles of attack up to 20 degrees. Measurements included surface pressure distributions, flow visualization using shadowgraph and Schlieren techniques, and digital holographic interferometry to obtain density distributions in the flowfield. Computational simulations of the inviscid flow were also performed using a three-dimensional Euler solver. The goal was to provide high-quality aerodynamic data to validate computational fluid dynamics codes for simulating high-speed flows with phenomena such as shocks, separation
A full experimental and numerical modelling of the practicability of thin foa...Mehran Naghizadeh
This paper presents the performance of geofoam-filled trenches in mitigating of ground vibration transmissions by the means of a full experimental study. The results are interpreted in the frequency domain. Fully automated 2D and 3D numerical models are applied to evaluate the screening effectiveness of geofoam-filled trenches in the active and passive schemes. Experimental results are in good agreement with the prediction of numerical modelling. The validated model is used to investigate the influence of geometrical and dimensional features on the trench. In addition, three different systems including single, double and triangle wall obstacles are selected for analysis, and the results are compared for various situations. The parametric study is based on complete automation of the model through coupling finite element analysis software (Plaxis) and Python programming language to control input, change the parameters, as well as to produce output and calculate the efficiency of the barrier. The results show that the depth and the width of approximately 1λr and 0.2λr, respectively are enough to reach the acceptable amount of efficiency for the active isolation for all three systems. For the passive scheme, the role of depth can be ignored for the single and double wall barriers, while depth plays a significant role for the triangle wall system.
Flow Modeling Based Wall Element TechniqueCSCJournals
Two types of flow where examined, pressure and combination of pressure and Coquette flow of confined turbulent flow with a one equation model used to depict the turbulent viscosity of confined flow in a smooth straight channel when a finite element technique based on a zone close to a solid wall has been adopted for predicting the distribution of the pertinent variables in this zone and examined even with case when the near wall zone was extended away from the wall. The validation of imposed technique has been tested and well compared with other techniques.
Laminar Flow And Turbulence Modeling For Domestic Scale Wind Turbine Sitingchittaranjang
This document discusses a computational fluid dynamics (CFD) simulation of wind flow and wake patterns around building clusters to identify suitable locations for installing domestic-scale wind turbines. The simulation models wind flow at different speeds and directions around a cluster of tall and medium-sized buildings. It analyzes wind speed and turbulence data to estimate wind power potential. The simulation results show a wide wake region on the leeward side of buildings that would be unsuitable for wind turbines due to low wind speeds. Proper turbine siting to avoid wake regions is important to maximize energy production and return on investment.
On The Form Factor Prediction Of A Displacement Type Vessel: JBC CaseIsmail Topal
This document summarizes a study on predicting the form factor of a displacement type vessel (JBC hull) using computational fluid dynamics (CFD). Single-phase CFD simulations were performed for the JBC hull at various velocities within the Prohaska range. The form factor, which represents the ratio of viscous pressure force to frictional force, was calculated from the simulations and found to depend on Reynolds number, contrary to Prohaska's theory of independence. Frictional force results matched well with empirical ITTC formulas. The study aims to further investigate scale effects on form factor prediction.
This document summarizes a study on predicting the form factor of a ship hull through computational fluid dynamics simulations. Researchers conducted single-phase CFD simulations of flow around a Japanese Bulk Carrier hull model at various velocities within the Prohaska range. They evaluated mesh dependency, calculated friction coefficients compared to empirical data, and analyzed the effect of Reynolds number on predicted form factors. The study found that the form factor depends on ship velocity, contrary to Prohaska's theory, and suggests further investigation of scale effects on form factor predictions.
Diffusers are extensively used in centrifugal
compressors, axial flow compressors, ram jets, combustion
chambers, inlet portions of jet engines and etc. A small change in
pressure recovery can increases the efficiency significantly.
Therefore diffusers are absolutely essential for good turbo
machinery performance. The geometric limitations in aircraft
applications where the diffusers need to be specially designed so
as to achieve maximum pressure recovery and avoiding flow
separation.
The study behind the investigation of flow separation in a planar
diffuser by varying the diffuser taper angle for axisymmetric
expansion. Numerical solution of 2D axisymmetric diffuser model
is validated for skin friction coefficient and pressure coefficient
along upper and bottom wall surfaces with the experimental
results of planar diffuser predicted by Vance Dippold and
Nicholas J. Georgiadis in NASA research center [2]
.
Further the diffuser taper angle is varied for other different
angles and results shows the effect of flow separation were it is
reduces i.e., for what angle and at which angle it is just avoided.
Numerical investigation of flow characteristics in aIAEME Publication
This document summarizes a numerical investigation of flow characteristics in a C-shaped subsonic diffuser. The study validated computational fluid dynamics (CFD) simulations with experimental data from a physical test rig. Key findings include:
1) Experimental results found a static pressure recovery of 35% and total pressure loss of 13% for a diffuser with an area ratio of 1.273.
2) CFD simulations using a standard k-ε turbulence model predicted a static pressure recovery of 38% and total pressure loss of 14%, in good agreement with experimental results.
3) Parametric CFD studies showed that static pressure recovery increases with area ratio but decreases with increasing angle of turn, while total
Prediction of aerodynamic characteristics for slender bluff bodies with nose ...vasishta bhargava
This document discusses numerical simulations of aerodynamic characteristics for slender bluff bodies with different nose cone shapes. Four cylinder models were analyzed: a conical nose (A), and blunt nose cones with tip diameters of 0.1m (B), 0.08m (C), and 0.06m (D). A panel method was used to calculate lift, drag, and pressure distributions at angles of attack from -10 to 20 degrees and velocities from 5-25 m/s. Pressure peaked on the suction side of the conical nose at -10 and 10 degrees. Blunt nose cylinders B, C, and D showed similar pressure distributions, with peaks shifting location compared to the conical nose. Veloc
Analysis of Wind Load Factors and Stability on Sensitive StructuresIRJET Journal
The document analyzes wind loads and stability on sensitive structures with curved roofs through wind tunnel experiments and computational fluid dynamics simulations. Curved roof models with different rise-to-span and wall height-to-span ratios were tested under uniform, open terrain, and suburban terrain wind conditions for a range of wind angles. The results show that wall height significantly affects wind pressures on the roof, with higher walls producing lower pressures in the windward quarter and higher suctions in the center and leeward quarters. Open and suburban terrains produce more variable pressures than uniform flow. The study provides pressure coefficient data to help establish wind loading for structural design of curved roofs.
Numerical and experimental investigation of co shedding vortex generated by t...Alexander Decker
The document investigates the effect of co-shedding vortices generated by two adjacent circular cylinders on air flow behavior around an NACA 2412 airfoil. Both experimental and numerical methods were used. Experimentally, a smoke wind tunnel was used to visualize flow at different velocities and angles of attack. Numerically, ANSYS was used to simulate results. The study found that the vortices induced turbulence upstream of the airfoil, preventing separation and allowing reattachment of the flow. Both methods showed that increasing angle of attack or velocity shifted the separation point toward the leading edge. The vortices generated by the cylinders thus helped control flow separation around the airfoil.
This document provides an overview of existing dispersion models and literature on modeling the dispersion of emissions from rooftop stacks. It summarizes key findings from previous studies on how increasing stack height and exhaust velocity can reduce pollutant concentrations at nearby receptors. However, it notes that field studies have sometimes found concentrations to be higher than predicted by models, due to factors like nearby buildings and atmospheric turbulence. The document then describes the ASHRAE geometric design method and dilution models that will be evaluated using new field data collected for this study.
03302--ICWE14-2015-Experimental and Numerical Evaluation of Micrositing in Co...Jussara M. Leite Mattuella
This document summarizes experimental and numerical research evaluating the speed-up effect in complex terrain areas. Wind tunnel experiments and computational fluid dynamics (CFD) simulations were used to analyze wind speed and turbulence intensity profiles above symmetrical hill models with slopes of 25, 32, 52, and 68 degrees, representing complex terrain. Both methods found increased wind speeds at hill crests due to the speed-up effect. The research aims to compare the two methods for analyzing the speed-up factor and how increased wind speeds could enable wind energy development in complex areas.
Numerical Modelling of Wind Patterns around a Solar Parabolic Trough CollectorIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Calculation of Fluid Dynamic for Wind Flow around Reinforced Concrete WallsIJERA Editor
A study on the flow phenomena around free-standing walls is important in practical building construction. In the present paper a numerical study is conducted for two- dimensional incompressible steady flow around freestanding walls using low-Re k-co turbulence model. The separation regions downstream the wall and on the roof of the leeward were predicted. Finally, results of numerical simulation are presented in the form of velocity vectors, velocity contour, pressure contours and streamlines
Effect of mainstream air velocity on velocity profile over a rough flat surfaceijceronline
1) The document discusses an experiment that measured the velocity profile over a rough flat surface at different locations along the surface (sections) and with varying mainstream air velocities.
2) The results showed that at a given location, velocity increased with increasing mainstream velocity. Additionally, boundary layer thickness increased with distance from the leading edge but decreased with increasing mainstream velocity.
3) In conclusion, the velocity over the rough surface was significantly influenced by the incoming air velocity, and boundary layer thickness varied inversely with mainstream velocity but directly with distance from the leading edge.
Trailing edge noise prediction from NACA 0012 and NACA 6320 using empirical p...vasishta bhargava
Trailing edge of airfoil represents one of important sources in aerodynamic noise production. In this paper, the numerical computation of sound pressure using quasi empirical model and wall pressure spectrum models based on external pressure gradients was conducted for NACA 0012 and NACA 6320 airfoils. The development of boundary layer thickness and displacement thickness for different chord lengths and Mach numbers with varying angles of attack, are illustrated for NACA 0012. The sound pressure levels evaluated between 00 to 60angles of attack and at constant chord length of 1.2m using BPM model showed change of ~5dB in peak amplitude. The maximum test velocity and chord length used for analysis is 65 m/s and 1.5m. The relative velocities for airfoils have been computed using the boundary element and panel method. Boundary layer properties involving chord Reynolds number, 3.14 x106, 4.6 x106and Reynolds number based on wall shear, 7410, 6865 were assessed at 20 AOA for NACA 0012. Results have found higher values for thickness at increasing angle of attack but decayed along chord length. Comparison of wall pressure spectrum for favorable and adverse pressure gradients were done and validated with existing literature predictions
IRJET - Wind Analysis of High Rise BuildingsIRJET Journal
This document discusses wind analysis methods for high-rise buildings. It presents a FORTRAN program developed to perform random vibration analysis (RVA) to determine the structural response of buildings due to wind loads. RVA considers both the mean and fluctuating components of deflection. The document also discusses codal analysis methods which can determine wind loads, shear forces, and bending moments on structures. It applies both RVA and codal analysis to evaluate wind loads on sample high-rise buildings and chimneys. The results are then compared to published literature values.
This document summarizes a numerical study of airflow over an Ahmed body using RANS turbulence models. It finds that the k-ε-v2 model more accurately predicts separation and reattachment compared to other models. The study simulates flow over an Ahmed body with a 35 degree rear angle using various turbulence models and investigates the effects of grid layout and differencing schemes on the results. Numerical results agree well with experimental data on the wake structure and turbulent kinetic energy distribution behind the body.
This document summarizes revisions made to the gust effect factor formulation in ASCE7-95 wind load provisions. It discusses concepts of spatial and temporal wind averaging and introduces the new gust effect factor. The factor is derived based on considerations of peak gust wind speeds, turbulence intensity, structure size, and other factors. Examples are provided to illustrate using the new provisions to evaluate gust effect factors for flexible structures.
This document describes an experimental and computational study of flow over a blunt cylinder-flare model in high supersonic flow. Wind tunnel experiments were conducted in the TST-27 and ST-15 wind tunnels at Mach numbers from 3 to 4 and angles of attack up to 20 degrees. Measurements included surface pressure distributions, flow visualization using shadowgraph and Schlieren techniques, and digital holographic interferometry to obtain density distributions in the flowfield. Computational simulations of the inviscid flow were also performed using a three-dimensional Euler solver. The goal was to provide high-quality aerodynamic data to validate computational fluid dynamics codes for simulating high-speed flows with phenomena such as shocks, separation
A full experimental and numerical modelling of the practicability of thin foa...Mehran Naghizadeh
This paper presents the performance of geofoam-filled trenches in mitigating of ground vibration transmissions by the means of a full experimental study. The results are interpreted in the frequency domain. Fully automated 2D and 3D numerical models are applied to evaluate the screening effectiveness of geofoam-filled trenches in the active and passive schemes. Experimental results are in good agreement with the prediction of numerical modelling. The validated model is used to investigate the influence of geometrical and dimensional features on the trench. In addition, three different systems including single, double and triangle wall obstacles are selected for analysis, and the results are compared for various situations. The parametric study is based on complete automation of the model through coupling finite element analysis software (Plaxis) and Python programming language to control input, change the parameters, as well as to produce output and calculate the efficiency of the barrier. The results show that the depth and the width of approximately 1λr and 0.2λr, respectively are enough to reach the acceptable amount of efficiency for the active isolation for all three systems. For the passive scheme, the role of depth can be ignored for the single and double wall barriers, while depth plays a significant role for the triangle wall system.
Flow Modeling Based Wall Element TechniqueCSCJournals
Two types of flow where examined, pressure and combination of pressure and Coquette flow of confined turbulent flow with a one equation model used to depict the turbulent viscosity of confined flow in a smooth straight channel when a finite element technique based on a zone close to a solid wall has been adopted for predicting the distribution of the pertinent variables in this zone and examined even with case when the near wall zone was extended away from the wall. The validation of imposed technique has been tested and well compared with other techniques.
Laminar Flow And Turbulence Modeling For Domestic Scale Wind Turbine Sitingchittaranjang
This document discusses a computational fluid dynamics (CFD) simulation of wind flow and wake patterns around building clusters to identify suitable locations for installing domestic-scale wind turbines. The simulation models wind flow at different speeds and directions around a cluster of tall and medium-sized buildings. It analyzes wind speed and turbulence data to estimate wind power potential. The simulation results show a wide wake region on the leeward side of buildings that would be unsuitable for wind turbines due to low wind speeds. Proper turbine siting to avoid wake regions is important to maximize energy production and return on investment.
On The Form Factor Prediction Of A Displacement Type Vessel: JBC CaseIsmail Topal
This document summarizes a study on predicting the form factor of a displacement type vessel (JBC hull) using computational fluid dynamics (CFD). Single-phase CFD simulations were performed for the JBC hull at various velocities within the Prohaska range. The form factor, which represents the ratio of viscous pressure force to frictional force, was calculated from the simulations and found to depend on Reynolds number, contrary to Prohaska's theory of independence. Frictional force results matched well with empirical ITTC formulas. The study aims to further investigate scale effects on form factor prediction.
This document summarizes a study on predicting the form factor of a ship hull through computational fluid dynamics simulations. Researchers conducted single-phase CFD simulations of flow around a Japanese Bulk Carrier hull model at various velocities within the Prohaska range. They evaluated mesh dependency, calculated friction coefficients compared to empirical data, and analyzed the effect of Reynolds number on predicted form factors. The study found that the form factor depends on ship velocity, contrary to Prohaska's theory, and suggests further investigation of scale effects on form factor predictions.
Diffusers are extensively used in centrifugal
compressors, axial flow compressors, ram jets, combustion
chambers, inlet portions of jet engines and etc. A small change in
pressure recovery can increases the efficiency significantly.
Therefore diffusers are absolutely essential for good turbo
machinery performance. The geometric limitations in aircraft
applications where the diffusers need to be specially designed so
as to achieve maximum pressure recovery and avoiding flow
separation.
The study behind the investigation of flow separation in a planar
diffuser by varying the diffuser taper angle for axisymmetric
expansion. Numerical solution of 2D axisymmetric diffuser model
is validated for skin friction coefficient and pressure coefficient
along upper and bottom wall surfaces with the experimental
results of planar diffuser predicted by Vance Dippold and
Nicholas J. Georgiadis in NASA research center [2]
.
Further the diffuser taper angle is varied for other different
angles and results shows the effect of flow separation were it is
reduces i.e., for what angle and at which angle it is just avoided.
Numerical investigation of flow characteristics in aIAEME Publication
This document summarizes a numerical investigation of flow characteristics in a C-shaped subsonic diffuser. The study validated computational fluid dynamics (CFD) simulations with experimental data from a physical test rig. Key findings include:
1) Experimental results found a static pressure recovery of 35% and total pressure loss of 13% for a diffuser with an area ratio of 1.273.
2) CFD simulations using a standard k-ε turbulence model predicted a static pressure recovery of 38% and total pressure loss of 14%, in good agreement with experimental results.
3) Parametric CFD studies showed that static pressure recovery increases with area ratio but decreases with increasing angle of turn, while total
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
How to Fix the Import Error in the Odoo 17Celine George
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
Assessment and Planning in Educational technology.pptxKavitha Krishnan
In an education system, it is understood that assessment is only for the students, but on the other hand, the Assessment of teachers is also an important aspect of the education system that ensures teachers are providing high-quality instruction to students. The assessment process can be used to provide feedback and support for professional development, to inform decisions about teacher retention or promotion, or to evaluate teacher effectiveness for accountability purposes.
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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