Aerodynamic Characteristic Analysis of Box Girder Section in TSI Gusty Wind

2020 ◽  
Vol 09 (01) ◽  
pp. 19-28
Author(s):  
菲 黄
Keyword(s):  
Aerodynamic Characteristic ◽  
Characteristic Analysis ◽  
Box Girder

A Method for Aerodynamic Characteristic Analysis of Hypersonic Aircraft Based on Response Surface Model

2013 ◽  
Vol 477-478 ◽  
pp. 277-280 ◽  
Author(s):  
Jie Yang ◽  
Song Ping Wu ◽  
Wen Xin Hou
Keyword(s):  
Flow Field ◽  
Response Surface ◽  
Aerodynamic Characteristic ◽  
Aerodynamic Characteristics ◽  
Surface Model ◽  
Complex Flow ◽  
Characteristic Analysis ◽  
Response Surface Models ◽  
Hypersonic Aircraft ◽  
Surface Models

Aerodynamic characteristic analysis of hypersonic cruise aircraft is more difficult than that of conventional aircraft, for the complex flow field simulation and inadequate amount of results under limited flight conditions. In this paper, numerical schemes applicable for hypersonic flow field are adopted to acquire a set of aerodynamic characteristics of a typical hypersonic cruise aircraft as sample data, based on which response surface models (RSM) are constructed to provide approximation of aerodynamic characteristics under any flight conditions within the design domain, finally the overall approximation performance of the response surface models are analyzed.

Rolling Moment Characteristic Analysis of Wrap-Around Fins

2010 ◽  
Vol 77 (5) ◽  
Author(s):  
Chen Xin-Hong ◽  
Zhao Run-Xiang
Keyword(s):  
Small Perturbation ◽  
Aerodynamic Characteristic ◽  
Pressure Coefficient ◽  
Angle Of Attack ◽  
Experimental Studies ◽  
Theoretical Method ◽  
Characteristic Analysis ◽  
Rolling Moment ◽  
Pressure Distributions ◽  
Perturbation Potential

A lot of numerical and experimental studies indicate that wrap-around fin configuration exhibits a self-induced rolling moment even at angle of attack zero. It depends on the unequal pressure distributions over both sides of the fin. In this paper, we try to prove this special aerodynamic characteristic with a theoretical method. According to the transonic small perturbation potential theory, as well as the transonic small perturbation potential equation, this paper found the expressions of the wrap-around fin convexity and the concave pressure coefficient at subsonic and supersonic by solving the Laplace equation and the Bessel function of imaginary argument, and analyze the phenomena of wrap-around fin rolling moment generation at angle of attack zero, and discuss the reason. The flow field of a projectile with wrap-around fins is solved by numerical method to check the pressure distributions of the two surfaces of the wing at subsonic and supersonic, respectively. The computational result is accordant to the theoretical analysis results. It is proved that the complicated pressure distribution of the wing surfaces leads to the particular characteristic of rolling moment.

Thermal Field Characteristics of Reinforced Concrete Box Girder during High-Temperature Asphalt Pavement Paving

2018 ◽  
Vol 2672 (41) ◽  
pp. 56-64 ◽  
Author(s):  
Dong Zheng ◽  
Zhen-dong Qian ◽  
De-xuan Liu ◽  
Xiang-fei Zhang ◽  
Yang Liu
Keyword(s):  
Reinforced Concrete ◽  
High Temperature ◽  
Thermal Field ◽  
Field Model ◽  
Asphalt Pavement ◽  
Structural Safety ◽  
Characteristic Analysis ◽  
Box Girder ◽  
Temperature Load ◽  
Concrete Box Girder

During high-temperature asphalt pavement paving, the bridge is subjected to significant temperature variations, and thereby the nonlinear thermal field distribution that occurs in the box girder might threaten the safety and serviceability of the bridge structures. Therefore, this study aims to investigate the thermal field characteristics of reinforced concrete box girder with steel fiber-reinforced concrete leveling layer during asphalt pavement paving. Firstly, a three-dimensional thermal field model of a reinforced concrete segmental box girder was developed and validated using the transient thermal field theory, and the dynamic paving process was simulated by the element deletion method. Secondly, the thermal field model was applied to analyze the vertical, transversal, and longitudinal temperature distribution during asphalt pavement paving. Thirdly, the effects of various sensitive factors on the thermal field of bridge components during asphalt pavement paving were evaluated. Finally, the extreme temperature load model was established through the statistical analysis method, in which the sensitive factors were introduced. Results demonstrate that the proposed numerical simulation method is feasible for thermal field characteristic analysis of reinforced concrete box girder during asphalt pavement paving. In addition, the research results can provide the theoretical foundation for temperature load selection and structural safety design of the concrete box girder during asphalt pavement paving.

Aerodynamic Characteristic Analysis of Flow Structure around the High-Speed Train Equipment Bay

2016 ◽  
Vol 693 ◽  
pp. 11-16 ◽  
Author(s):  
Yong Chang Zhang ◽  
Yu Gong Xu ◽  
Le Le Zhang
Keyword(s):  
Spectral Analysis ◽  
Flow Structure ◽  
Pressure Fluctuation ◽  
High Speed ◽  
Aerodynamic Characteristic ◽  
Influence Factors ◽  
High Speed Train ◽  
Characteristic Analysis ◽  
Train Speed ◽  
Improved Model

An improved train model, which contributes to obtain the aerodynamic characteristic of the high-speed train equipment bay, is established. By building a VEB (vehicle equipment bay) model in it, this improved model can demonstrate air flow around the VEB. The result shows that pressure fluctuation appears around the VEB, which gives visible difference from the classical train model. Applying the spectral analysis, the influence factors (include position and train speed) of the pressure fluctuation is studied.

Aerodynamic Characteristic Analysis of Two-Dimensional Trajectory Corrector Projectile in Mortar

2014 ◽  
Vol 624 ◽  
pp. 236-239
Author(s):  
Tong Zhang ◽  
Xiao Li Zhao ◽  
Zhen Dong Song
Keyword(s):  
Aerodynamic Characteristic ◽  
Lift Coefficient ◽  
Simulation Models ◽  
Future Research ◽  
Pitching Moment ◽  
Two Dimensional ◽  
Characteristic Analysis ◽  
Data Simulation ◽  
Moment Coefficient ◽  
Simulation Results

Aiming at researching aerodynamic characteristic of projectiles. This paper builds three simulation models with fins in different amount and appearance, by using CFD software to generate meshes of each model, it simulates the changing laws of drag coefficient, lift coefficient and pitching moment coefficient and analyses correct ability and flight stability of each model according to the data, simulation results indicate that projectile with folded fins have better aerodynamic appearance and can be studied deeper, it provides aerodynamic reference for future research.

1842: Catheter Free Potassium-Titanyl-Phosphate (KTP) Laser Photoselective Vaporization Prostatectomy (PVP): Patient Characteristic Analysis

2007 ◽  
Vol 177 (4S) ◽  
pp. 612-612
Author(s):  
Motoo Araki ◽  
Po N. Lam ◽  
Daniel J. Culkin ◽  
Pamela E. Fox ◽  
Glenn M. Sulley ◽  
...  
Keyword(s):  
Potassium Titanyl Phosphate ◽  
Ktp Laser ◽  
Characteristic Analysis ◽  
Photoselective Vaporization
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