A5014465090- Aerodynamics and Fluid Dynamics Research
- Wind and Air Flow Studies
- Fluid Dynamics and Vibration Analysis
- Fluid Dynamics and Turbulent Flows
- Vehicle emissions and performance
Central South University
2022-2024
State Key Laboratory of Vehicle NVH and Safety Technology
2022-2023
Ministry of Transport
2022-2023
This study attempts to describe associated fluid dynamics of a square finite wall-mounted cylinder (FWMC) immersed within free-stream turbulent flow characterized by different turbulence intensities and integral length scales. An improved delayed detached eddy simulation method is adopted numerically reproduce the fully developed fields. The results reveal that both scales have significant effect on separated shear layers, base pressure, aerodynamic forces cylinder. Constrained streamlines...
The turbulence intensity and yaw angle of crosswinds exert a substantial impact on the aerodynamic characteristics trains traveling in windy regions. It is urgent to study how incoming flow jointly affect train corresponding field under turbulent crosswind. A high-speed scaled at ratio 1/8 its actual size different angles was investigated. Three inflow conditions were adopted, including uniform inflow, Iu = 0.05 0.2 (Iu intensity). generated by synthetic eddy method. instantaneous time...
Turbulent incoming flow conditions are closely matched to the crosswinds experienced by trains in windy areas. Therefore, it is important investigate how turbulent inflow affects dynamics around a train. The aerodynamic characteristics of 1:8-scaled high-speed train at 90° yaw angle were studied based on improved delayed detached eddy simulation (IDDES) turbulence model. Four set using synthetic method (SEM) generator, including uniform, Lu = 0.5H, 1H, and 2H (Lu integral length scale H...
Flow control of cylinders aimed at drag reduction or vibration suppression has been widely studied. Sweeping jet is a novel flow method that applied to airfoil and other bluff bodies. This paper numerically investigates the effects sweeping jets on cylinder Reynolds number 5 × 104 using large Eddy simulation. Various parameters such as angle, momentum coefficient, arrangement configuration fluidic oscillators are examined for their influence effectiveness. The results demonstrate...
As train speeds increase, the outer windshields become susceptible to vibration deformation and fatigue damage under aerodynamic forces. Previous research on treated them as rigid structures, neglecting interaction between excitation windshield vibration. This paper proposes unsteady Reynolds-averaged Navier–Stokes turbulence model fluid–structure (FSI) method study of windshields. The numerical method's accuracy reliability are validated through full-scale test data videos. Step heights...
A significant airflow acceleration effect generated by canyon terrain and the bridge poses a serious threat to safety of train operation in wind zone. The scale-resolving hybrid turbulence model overset mesh technology have been employed investigate aerodynamic performance traversing tunnel–bridge–tunnel infrastructure under wind. Meanwhile, mechanism load variation is explored combination with characteristics field distribution. results indicate that speed reaching windward track about...
Research on aerodynamic loads and flow field characteristics of trains under real wind gust is limited. Most studies focus train's dynamics gust. By using numerical simulation methods to model the spatiotemporal evolution around train gust, load were studied. The one-minus-cosine was adopted achieve improved delayed detached eddy based shear stress transport k–ω turbulence used perform simulations operation by applying specified function velocity inlet boundary. During peak values for most...
By using three different head types (5 m, 7.5 m and 10 nose lengths), the CRH3 (China Railway High-speed 3) flow field structure at 15° yaw was studied through wind tunnel experiments numerical simulations. The modifications of aerodynamic coefficients were Improved Delayed Separation Eddy Simulation (IDDES) method. results show that longer length tail car, more it is affected by crosswind. However, increase in turbulence mitigates risk overturning car as pressure distribution between train...