Large Eddy Simulation of the Flow-Field around Road Vehicle Subjected to
                        Pitching Motion

Gu, Zhongde; Huang, Taiming; Chen, Z.; Zong, Yuan; Zeng, Wei

doi:10.29252/jafm.09.06.25330

Cited by 3 publications

(2 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Two different vertical heightadjustable devices in wind tunnel could realize quasistatic and dynamic angle change of attack of the model at which the phenomena of hysteresis and phase-shifting occurred in total pressure loss coefficients (Gilliéron et al 2003). The hysteresis effects were also found in simulation (Krajnović et al 2011;Gu et al 2016). Nakashima et al (2009) performed a numerical analysis of two kinds of simplified vehicle models with regard to vehicle pitch motion, comparing the result of the quasisteady method with a non-stationary condition through the Arbitrary Lagrange-Euler (ALE) method to realize dynamic pitch motion.…”

Section: Introductionmentioning

confidence: 92%

Coupled Analysis of Transient Aerodynamic Characteristics of the Coach under Crosswind in Different Situations

2021

JAFM

View full text Add to dashboard Cite

The purpose of this work is to investigate transient aerodynamic characteristics of the coach under the crosswind in straight-line situations with different uniform speeds and uniform accelerations. The transient aerodynamics caused by different speed changes are analyzed using the real-time interaction between aerodynamic simulation and dynamic simulation. The target model is a simplified coach on a full scale. The SST (Menter) K-Omega Improved Delayed Detached Eddy Simulation and overset mesh technique are used to predict the transient aerodynamic loads. The accuracy of the turbulence model is verified by a wind tunnel experiment of the 1/7th scaled coach model. The present results show that the transient aerodynamic loads have different locations of maximum side force and the holding duration of yaw moment for different constant speeds. The speed becomes larger, and the position where the side force is maximum becomes farther away. The holding duration of the top yaw moment is larger simultaneously. Moreover, proper acceleration for low initial driving speed and crosswind of small influence range could build up stability. High speed driving in gust wind is not suggested for unskilled drivers.

show abstract

Section: Introductionmentioning

confidence: 92%

Coupled Analysis of Transient Aerodynamic Characteristics of the Coach under Crosswind in Different Situations

2021

JAFM

View full text Add to dashboard Cite

show abstract

“…RANS averages the control equations to avoid solving turbulent pulsations of various scales, reducing the calculation workload but also reducing calculation accuracy (Choudhary et al , 2023). LES directly solves large vortices using the N-S equation and uses a sub-grid model to consider the influence of small vortices (Gu et al , 2016). However, LES requires a large number of grids, longer calculation time and more resources (Favre and Efraimsson, 2011).…”

Section: Introductionmentioning

confidence: 99%

The influence of vehicle body roll motion on aerodynamic characteristics under crosswind condition

Taiming,

Ma,

Zhang

et al. 2023

HFF

View full text Add to dashboard Cite

Purpose The purpose of this study is investigate the transient aerodynamic characteristics of high-speed vehicle with body roll motion under crosswind condition to improve aerodynamic stability. Design/methodology/approach An overset mesh was used to simulate the rolling motion of the vehicle body. A wind tunnel experiment was conducted to validate the numerical method. Findings The results revealed that the vehicle’s aerodynamic characteristics changed periodically with the body’s periodic motion. In the absence of crosswind, the pressure distribution on the left and right sides of the vehicle body was symmetrical, and the speed streamline flowed to the rear of the vehicle in an orderly manner. The maximum aerodynamic lift observed in the transient simulation was −0.089, which is approximately 0.70 times that of the quasi-static simulation experiment. In addition, the maximum aerodynamic side force observed in the transient simulation was 0.654, which is approximately 1.25 times that of the quasi-static simulation experiment. Originality/value The aerodynamic load varies periodically with the vehicle body’s cyclic motion. However, the extreme values of the aerodynamic load do not occur when the vehicle body is at its highest or lowest position. This phenomenon is primarily attributed to the mutual interference of airflow viscosity and the hysteresis effect in the flow field, leading to the formation of a substantial vortex near the wheel. Consequently, the aerodynamic coefficient at each horizontal position becomes inconsistent during the periodic rolling of the vehicle body.

show abstract

Coupled Analysis of Unsteady Aerodynamics and Vehicle Motion of a Passenger Car in Crosswind Condition

Huang

Feng

2017

JAFM

Self Cite

View full text Add to dashboard Cite

High-speed passenger car requires a lighter weight for improving power performance and reducing fuel consumption; a car with higher-speed and lighter weight will lead to the passenger car more sensitive to the crosswind, which will affect the stability and drivability of the passenger car. This study employs the fully-coupled method to investigate a passenger car subjected "1-cos" crosswind with consideration of the vehicle motion. Large eddy simulation (LES) and dynamic mesh is adopted to investigate the unsteady aerodynamic, and the vehicle is treated as a three-freedom-system and driver's control is considered to investigate the vehicle dynamic. The one-way simulation and quasi-steady simulation are also conducted to compare with the fully-coupled simulation. The results of the three simulation methods show large difference. The peak value of the lateral displacement in fully-coupled simulation is the smallest between the three simulation approaches. While the change of aerodynamic loads and vehicle motion in fully-coupled simulation is more complicated than in one-way and quasi-steady simulation. These results clearly indicate the significance of including of the unsteady aerodynamic loads in passenger car moving analysis.

show abstract

Large Eddy Simulation of the Flow-Field around Road Vehicle Subjected to Pitching Motion

Cited by 3 publications

References 29 publications

Coupled Analysis of Transient Aerodynamic Characteristics of the Coach under Crosswind in Different Situations

Coupled Analysis of Transient Aerodynamic Characteristics of the Coach under Crosswind in Different Situations

The influence of vehicle body roll motion on aerodynamic characteristics under crosswind condition

Coupled Analysis of Unsteady Aerodynamics and Vehicle Motion of a Passenger Car in Crosswind Condition

Contact Info

Product

Resources

About