Experimental Study and Numerical Simulation of Domes Under Wind Load

2009 ◽  
Author(s):  
H. Al-Hashimi ◽  
A. C. Seibi ◽  
A. Molki
Keyword(s):  
Numerical Simulation ◽  
Experimental Study ◽  
Wind Speed ◽  
Pressure Distribution ◽  
Structural Integrity ◽  
Material Selection ◽  
Flow Behavior ◽  
Air Flow ◽  
Pressure Vessels ◽  
Experimental Results

Dome structures are of architectural significance in many applications ranging from building decorations to fluid confinement usage such as pressure vessels and storage tanks in the petrochemical industry. Most domes are subjected to severe external loads caused by wind flow. Therefore, careful material selection and structural design of domes is imperative to avoid any unexpected failure. This paper presents the design of an experimental set-up to study the flow behavior around ABS dome models of hemispherical and elliptical shapes and their structural integrity under wind loads. The objective of this paper is to determine the dome’s wall thickness for various geometrical shapes. The domes were placed inside a wind tunnel where the wind speed was varied from 60 to 100 km/hr and pressure distribution on the surface of the dome roof was measured. Pressure measurements were carried out for various attack angles with respect to its centerline using a data acquisition system programmed in LabVIEW™. In addition, flow visualization of the air flow around the dome was carried out using a smoke generator. The experimental study was supplemented by a numerical simulation of the air flow around domes to mimic experiments using Computational Fluid Dynamics (CFD) techniques. The effect of wind on the dome structural integrity was studied using finite element analysis. The experimental results were used to validate the CFD models from which pressure distribution around domes were obtained. Results related to the pressure distribution around domes obtained from the CFD analysis were used as loading conditions to study the structural integrity of the domes using ANSYS™. Preliminary experimental results of wind speed effect on a hemispherical/elliptical dome revealed pressure variations for various angles of attack and height inclination along the dome roof surface.

Experimental Study on Semi-Solid Indirect Squeeze Casting

2012 ◽  
Vol 192-193 ◽  
pp. 410-414
Author(s):  
Pei Wei Bao ◽  
Shu Ming Xing
Keyword(s):  
Numerical Simulation ◽  
Experimental Study ◽  
Process Improvement ◽  
Squeeze Casting ◽  
Experimental Results ◽  
Runner Design ◽  
Semi Solid ◽  
Layer Coating

In the Semi-Solid Processing of indirect squeeze casting, runners were needed for each part cavity. In our experiment, it was found that some of the runners were blocked, and some parts were not filling in full mold. Numerical simulation was applied to analyze this phenomenon, and the results show that it was the shell which emerged on the chamber surface that blocked the runner. Experimental results also confirmed our interpretation. Some measures have been used to correct it, such as runner design, two-layer coating, and process improvement which eliminated blocking of the runner.

Development of Prediction Technology of Two-Phase Flow Dynamics Under Earthquake Acceleration: (12) Bubble Motion Along the Flow in Structure Vibration

2014 ◽  
Author(s):  
Yuki Kato ◽  
Rie Arai ◽  
Akiko Kaneko ◽  
Hideaki Monji ◽  
Yutaka Abe ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Velocity Field ◽  
Test Section ◽  
Two Phase Flow ◽  
Flow Behavior ◽  
Bubbly Flow ◽  
Experimental Results ◽  
Phase Flow ◽  
Bubble Motion ◽  
Two Phase

In a nuclear power plant, one of the important issues is an evaluation of the safety of the reactor core and its pipes when an earthquake occurs. Many researchers have conducted studies on constructions of plants. Consequently, there is some knowledge about earthquake-resisting designs. However the influence of an earthquake vibration on thermal fluid inside a nuclear reactor plant is not fully understood. Especially, there is little knowledge how coolant in a core response when large earthquake acceleration is added. Some studies about the response of fluid to the vibration were carried out. And it is supposed that the void fraction and/or the power of core are fluctuated with the oscillation by the experiments and numerical analysis. However the detailed mechanism about a kinetic response of gas and liquid phases is not enough investigated, therefore the aim of this study is to clarify the influence of vibration of construction on bubbly flow behavior. In order to investigate the influence of vibration of construction on bubbly flow behavior, we visualized bubbly flow in pipeline on which sine wave was applied. In a test section, bubbly flow was produced by injecting gas into liquid flow through a horizontal circular pipe. In order to vibrate the test section, an oscillating table was used. The frequency and acceleration of vibration added from the oscillating table was from 1.0 Hz to 10 Hz and . 0.4 G (1 G=9.8 m/s2) at each frequency. The test section and a high speed video camera were fixed on the oscillating table. Thus the relative velocity between the camera and the test section was ignored. PIV measurement was also conducted to investigate interaction between bubble motion and surround in flow structure. Liquid pressure was also measured at upstream and downstream of the test section. The effects of oscillation on bubbly flow were quantitatively evaluated by these pressure measurements and the velocity field. In the results, it was observed that the difference of bubble motion by changing oscillation frequency. Moreover it was suggested that the bubble deformation is correlated with the fluctuation of liquid velocity field around the bubble and the pressure gradient in the flow area. In addition, these experimental results were compared with numerical simulation by a detailed two-phase flow simulation code with an advanced interface tracking method, TPFIT. Numerical simulation was qualitatively agreed with experimental results.

Study of a W-Beam Guardrail Behaviour in Road Safety Barriers

2014 ◽  
Vol 1016 ◽  
pp. 54-58
Author(s):  
Nuno Peixinho ◽  
João Tavares ◽  
José Meireles
Keyword(s):  
Numerical Simulation ◽  
Experimental Study ◽  
Road Safety ◽  
Experimental Results ◽  
Safety Barriers ◽  
Plastic Domain ◽  
Plastic Displacement ◽  
Force Displacement ◽  
Ansys Workbench

This study presents results regarding a numerical simulation of the plastic displacement of a road guardrail. An experimental study of two different guardrails was conducted in order to collect information regarding displacement due to a determined force behavior. These tests were then simulated in Ansys Workbench to recreate the elastic and plastic domain of the material. The guardrails are two meters long, supported by two simple cylinders while being pressed at the center by a third one. In order to explore the software two different mesh sizes were used to compare their efficiency, being concluded with the comparison between the force-displacement curves of numerical and experimental results.

Numerical Simulation & Experimental study of wear depth and Contact pressure distribution Of Aluminum MMC Pin on Disc Tribometer.

2017 ◽  
Vol 4 (10) ◽  
pp. 11218-11228 ◽  
Author(s):  
R. Suresh ◽  
M. Prasanna Kumar ◽  
S. Basavarajappa ◽  
T.S. Kiran ◽  
Mahesh Yeole ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Experimental Study ◽  
Pressure Distribution ◽  
Contact Pressure ◽  
Wear Depth ◽  
Contact Pressure Distribution ◽  
Pin On Disc

Experimental Study on the Effect of Jet Penetrating into Disconnected Targets with Water Medium

2013 ◽  
Vol 834-836 ◽  
pp. 787-790
Author(s):  
Hong Chao Gao ◽  
Xing Bai Luo
Keyword(s):  
Numerical Simulation ◽  
Adverse Effect ◽  
Experimental Study ◽  
Experimental Method ◽  
Shaped Charge ◽  
Experimental Results ◽  
Medium Effect ◽  
Water Medium ◽  
Target Interval ◽  
Jet Penetration

Using the experimental method for water medium interval target how to affect the ability of the jet penetration degree is determined. In order to verify the target interval between target and target medium effect on the jet penetration, with a shaped charge respectively on the interval of air and water medium target penetration experiment, the experimental results show that water medium for jet penetration does exist more adverse effect than air. It is combined with numerical simulation and experimental results to revise penetration of traditional formula.

Effect of the Distance between Guided Needle and Cone Body on Properties of Vortex Spun Yarn

2014 ◽  
Vol 1048 ◽  
pp. 575-578
Author(s):  
Mei Ling Li ◽  
Chong Wen Yu ◽  
Shan Shan Shang
Keyword(s):  
Fluid Dynamics ◽  
Numerical Simulation ◽  
Computational Fluid Dynamics ◽  
Pressure Distribution ◽  
Air Flow ◽  
Yarn Quality ◽  
Spun Yarn ◽  
Simulation Results ◽  
Dynamics Models

Effects of the distance between guided needle and cone body on properties of MVS yarns were investigated by numerical simulation. 5 groups of the distance are designed (0.5mm, 1mm, 1.5mm, 2mm and 2.5mm). The 3D computational fluid dynamics models are established to conduct the numerical simulation of the airflow in the nozzle. Through analysis of the characteristics of air flow inside the different nozzles, such as pressure distribution and velocity vectors, the motion of drafted fibers and performances of yarns are discussed. Simulation results show that when the distance is 1.5mm, the airflow state within the nozzle is beneficial to form more open-ends and twist, and the yarn quality would be better.

Numerical Simulation and Experimental Study on the Contact Pressure between Bipolar Plate and GDL in a PEM Fuel Cell

2015 ◽  
Vol 750 ◽  
pp. 220-225
Author(s):  
Xue Mei Han ◽  
Jin Zhu Tan ◽  
Yong Chang Liu ◽  
Peng Li ◽  
Long Pan
Keyword(s):  
Experimental Study ◽  
Finite Element ◽  
Fuel Cell ◽  
Pressure Distribution ◽  
Contact Pressure ◽  
Operating Temperature ◽  
Pem Fuel Cell ◽  
Bipolar Plate ◽  
Experimental Results ◽  
Contact Pressure Distribution

Both assembly force and temperature play an important role in the proton exchange membrane (PEM) fuel cell performance. In this paper, contact pressure between bipolar plate and gas diffusion layer (GDL) in a PEM fuel cell under various assembly forces and at different temperatures was studied numerically. Considering the coupling effects of assembly force and operating temperature on contact pressure, a three-dimensional finite element model of the PEM fuel cell was established and the contact pressure between the GDL and the bipolar plate was studied using commercial code ABAQUS. In order to verify the simulated results, the experimental study was conducted to investigate the contact pressure distribution between the bipolar plate and the GDL. The experimental results are in good agreement with the finite element method (FEM) results. The simulated and experimental results reveal that the contact pressure increased with the increase of assembly force and temperature. It is found that the contact pressure distribution between the bipolar plate and the GDL had the best uniformity under the applied torque of 3.0N·m and at the operating temperature of 80 °C in this work.

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