Study of Influence of Wind Fluctuation on Scattering Side Force Coefficient for Intermediate Car of Railway

Thebased SST (shear strain transport) turbulence model combines the advantages of and turbulence models and performs well in numerical experiment. In the paper, the SST turbulence model is applied to model vehicle overtaking process with numerical simulation technology. The change graph of drag coefficient and side force coefficient are gained. Analysis of the phenomena is presented at the end.

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Side force coefficient estimation for the design of active brake control

2006 American Control Conference ◽

10.1109/acc.2006.1657164 ◽

2006 ◽

Cited By ~ 7

Author(s):

P. Gaspar ◽

Z. Szabo ◽

J. Bokor

Keyword(s):

Force Coefficient ◽

Side Force ◽

Coefficient Estimation ◽

Side Force Coefficient

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Influence of Rectangular Strips’ Size on Aerodynamic Performance of a High-Speed Train Subjected to Crosswind

10.1115/fedsm2021-65692 ◽

2021 ◽

Author(s):

Mengying Wang ◽

Zhenxu Sun ◽

Shengjun Ju ◽

Guowei Yang

Keyword(s):

High Speed ◽

Aerodynamic Performance ◽

Design Parameters ◽

Orthogonal Experimental Design ◽

High Speed Train ◽

Force Coefficient ◽

Roll Moment ◽

Side Force ◽

Moment Coefficient ◽

Side Force Coefficient

Abstract Conventional studies usually assume that the train surface is smooth, so as to simplify the numerical calculation. In fact, the surface of the train is irregular, which will change the flow characteristics in the boundary layer and further affect the aerodynamic performance of a train. In this work, roughness is applied to the roof of a 1:25 scaled train model in the form of longitudinal strips. Firstly, the improved delayed detached eddy simulation (IDDES) method is adopted to simulate the aerodynamic performance of the train model with both smooth and rough surface, which are subjected to crosswind. Results show that the side force coefficient and the roll moment coefficient subjected to rough model decreased by 3.71% and 10.56% compared with the smooth model. Then, the width, height and length of the strips are selected as variables to design different numerical simulation schemes based on the orthogonal experimental design method. Through variance analysis, it can be found that four design parameters have no significant effect on the side force coefficient. Meanwhile, for the roll moment coefficient, the length of the strips in the straight region of the train has a significant effect and the width of the strips has a highly significant effect on it. These conclusions can provide a theoretical basis to improve the aerodynamic performance of the high-speed train subjected to crosswind.

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EFFECT OF SILICA LOADING AND COUPLING AGENT ON WEAR AND FATIGUE PROPERTIES OF A TREAD COMPOUND

Rubber Chemistry and Technology ◽

10.5254/rct.18.81570 ◽

2018 ◽

Vol 92 (2) ◽

pp. 326-349 ◽

Cited By ~ 1

Author(s):

Harini Sridharan ◽

Abhilash Guha ◽

Sanjay Bhattacharyya ◽

Anil K. Bhowmick ◽

R. Mukhopadhyay

Keyword(s):

Crack Growth ◽

Coupling Agent ◽

Abrasion Resistance ◽

Rubber Matrix ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Force Coefficient ◽

Side Force ◽

Tan Δ ◽

Side Force Coefficient

ABSTRACT The effects of highly dispersible silica and the nature of silane in a tire tread cap compound were studied with particular reference to dynamic mechanical properties, abrasion resistance, side force coefficient, and fatigue crack growth (FCG) properties. The rubber matrix chosen was a blend of solution grade styrene butadiene rubber and polybutadiene rubber. Six different loadings of silica were used. Bistriethoxysilylpropyltetrasulfide (S) was taken as the coupling agent. In addition, the potential of two new generation silanes, 3-octanoylthio-1-propyltriethoxysilane (N) and 3-mercaptopropyl-di [tridecan-1-oxy-13-penta ethyleneoxideethoxysilane] (V) was also explored at 70 phr silica loading. Optimum properties were obtained at 50 phr loading of silica (S50). The tensile moduli for the compounds increased sharply with silica loading. Higher values of tan δ, indicating higher hysteresis, were obtained in compounds containing higher filler dosage. However, enhanced abrasion resistance and side force coefficient were observed at higher loadings of silica due to an increased reinforcement phenomenon. The crack growth exponent (β) was lowest for S50. Among the silanes tested, V showed a 22% drop in tan δ at 70 °C, 11% drop in abrasion loss, and an increase in FCG rate. N exhibited a lower FCG rate as compared with the silane S.

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Side Force Coefficient Evaluation of a Commercial Bus with Vortex Generators

10.26678/abcm.cobem2019.cob2019-1346 ◽

2019 ◽

Author(s):

Daniel Garcia Ribeiro ◽

Juan Flores Mezarina ◽

Pedro David Bravo-Mosquera ◽

Hernán Cerón-Muñoz ◽

John Jairo Vaca-Rios

Keyword(s):

Vortex Generators ◽

Force Coefficient ◽

Side Force ◽

Side Force Coefficient

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The Effects of Split Drag Flaps on Directional Motion of UiTM’s BWB UAV Baseline-II E-4: Investigation Based on CFD Approach

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.584 ◽

2012 ◽

Vol 433-440 ◽

pp. 584-588 ◽

Cited By ~ 3

Author(s):

Firdaus Mohamad ◽

Wisnoe Wirachman ◽

Wahyu Kuntjoro ◽

Rizal E M Nasir

Keyword(s):

Force Coefficient ◽

Side Force ◽

Moment Coefficient ◽

Dimensionless Coefficient ◽

Directional Motion ◽

Aerial Vehicle ◽

Blended Wing Body ◽

Control Surfaces ◽

Side Force Coefficient ◽

Linear Trends

This paper presents a study about split drag flaps as control surfaces to generate yawing motion of a blended wing body aircraft. These flaps are attached on UiTM’s Blended Wing Body (BWB) Unmanned Aerial Vehicle (UAV) Baseline-II E-4. Deflection of split drag flaps on one side of the wing will produce asymmetric drag force and, as consequences, yawing moment will be produced. The yawing moment produced will rotate the nose of the BWB toward the wing with deflected split drag flaps. The study has been carried out using Computational Fluid Dynamics to obtain aerodynamics data with respect to various sideslip angles (ß). The simulation is running at 0.1 Mach number or about 35 m/s. Results in terms of dimensionless coefficient such as drag coefficient (CD), side force coefficient (CS) and yawing moment coefficient (Cn) are used to observe the effects of split drag Subscript text flaps on the yawing moment. All the results obtained shows linear trends for all curves with respect to sideslip angles (ß).

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Spectral Techniques Applied to Evaluate Pavement Friction and Surface Texture

Coatings ◽

10.3390/coatings10040424 ◽

2020 ◽

Vol 10 (4) ◽

pp. 424

Author(s):

Yuan Yan ◽

Maoping Ran ◽

Ulf Sandberg ◽

Xinglin Zhou ◽

Shenqing Xiao

Keyword(s):

Spectral Analysis ◽

Surface Texture ◽

Spectral Band ◽

Force Coefficient ◽

Spectral Techniques ◽

Side Force ◽

Texture Parameters ◽

Texture Characteristics ◽

Pavement Friction ◽

Side Force Coefficient

To study texture of pavement surfaces and its effect on pavement friction, this article features a field experiment conducted on in-service pavements to characterize surface texture by spectral analysis to substantiate links to friction values. Pavement friction was measured using a Mu-meter and British pendulum tester whereas texture data was collected using a stationary laser profilometer. Texture spectra were analyzed and expressed in third octave bands. The correlation between texture spectral levels and friction values at different speeds are discussed in the paper. Results show that the texture level, including spectral band levels, can well represent texture characteristics, as texture spectral levels have a good correlation with friction coefficient, especially the texture level of texture wavelengths at 1.25–12.5 mm versus SFCsl (representing the slope of the side force coefficient (SFC) versus speed), i.e., the slope of friction versus speed. This friction parameter gives better correlations with texture parameters than friction values at different speeds, which is believed to be an effect of the drainage caused by texture in that wavelength range.

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Wind Loading on Articulated Trailers During Tipping

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/pime_proc_1995_209_190_02 ◽

1995 ◽

Vol 209 (2) ◽

pp. 103-110

Author(s):

H Fessler ◽

T H Hyde ◽

W Sun

Keyword(s):

Reynolds Number ◽

Lateral Force ◽

The Body ◽

Scale Model ◽

Wind Loading ◽

Wind Force ◽

Force Coefficient ◽

Side Force ◽

Side Force Coefficient ◽

Lateral Area

Modern articulated trucks have very large trailers, up to 11 m long. When they empty their load, the body may be inclined at up to 40° this causes a high obstruction to sideways winds, which may cause the vehicle to roll over. The lateral force and the roll-over moment were measured in wind tunnel tests of a 1/60 scale model of a typical truck with the body at different tipping angles, ψ, and the wind in different directions, α. The side force coefficient was found to be approximately 1.5, almost independent of ψ, α up to 15° and Reynolds number up to 340000. The resultant of the wind force was found to act at almost the same height above the ground as the centroid of the lateral area for all values of ψ.

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Numerical studies on aerodynamics of high-speed railway train subjected to strong crosswind

Advances in Mechanical Engineering ◽

10.1177/1687814019887270 ◽

2019 ◽

Vol 11 (11) ◽

pp. 168781401988727

Author(s):

Xu Wang ◽

Yuanhao Qian ◽

Zengshun Chen ◽

Xiao Zhou ◽

Huaqiang Li ◽

...

Keyword(s):

Wind Speed ◽

High Speed ◽

Lift Coefficient ◽

Aerodynamic Characteristics ◽

Width Ratio ◽

Force Coefficient ◽

Rolling Moment ◽

Side Force ◽

Train Speed ◽

Yaw Angle

Under the action of strong crosswind, the aerodynamic behavior of a rail vehicle at high speed will be changed significantly, which could directly affect the safe operation of the vehicle. With the help of the shape of train used in China, the aerodynamic characteristics of trains with scale of 1:1 is investigated using computational fluid dynamics numerical simulation method, which consists of the variation of aerodynamics force and moment with wind yaw angle, wind speed, train speed, and nose shape. After an initial validation against Baker’s results from wind tunnel test, the numerical model is then used to investigate the aerodynamic characteristics of the trains. The numerical results indicate that lift coefficient of the M train is slightly higher than TMC1 and TMC2 trains. Regardless of aerodynamics force coefficients, TMC1 reaches the maximum at a yaw angle of 75°. Aerodynamics force coefficient increases with both wind speed and train speed, but the change of which is not linear. Comparing aerodynamic force with different geometric dimensions of train nose, it is shown that height–width ratio is insensitive to side force and rolling moment, but sensitive to lift force from the yaw angle 0°–90°. The side force coefficient, as we most concern, is less than other results, when the length–width ratio is 1 and height–width is 0.87.

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