scholarly journals Modeling Emission Flow Pattern of a Single Cruising Vehicle on Urban Streets with CFD Simulation and Wind Tunnel Validation

2020 ◽  
Vol 17 (12) ◽  
pp. 4557 ◽  
Author(s):  
Xueqing Shi ◽  
Daniel (Jian) Sun ◽  
Ying Zhang ◽  
Jing Xiong ◽  
Zhonghua Zhao
Keyword(s):  
Numerical Simulation ◽  
Wind Tunnel ◽  
Flow Pattern ◽  
Cfd Simulation ◽  
Wind Tunnel Experiment ◽  
Atmospheric Pollutants ◽  
Future Application ◽  
Dispersion Pattern ◽  
Strong Positive Correlation ◽  
Cfd Numerical Simulation

Transportation has become one of the primary sources of urban atmospheric pollutants and it causes severe diseases among city residents. This study focuses on assessing the pollutant dispersion pattern using computational fluid dynamics (CFD) numerical simulation, with the effect and results validated by the results from wind tunnel experiments. First, the wind tunnel experiment was carefully designed to preliminarily assess the flow pattern of vehicle emissions. Next, the spatiotemporal distribution of pollutant concentrations around the motor vehicle was modeled using a CFD numerical simulation. The pollutant concentration contours indicated that the diffusion process of carbon monoxide mainly occurred in the range of 0−2 m above the ground. Meanwhile, to verify the correctness of the CFD simulation, pressure distributions of seven selected points that were perpendicular along the midline of the vehicle surface were obtained from both the wind tunnel experiment and the CFD numerical simulation. The Pearson correlation coefficient between the numerical simulation and the wind tunnel measurement was 0.98, indicating a strong positive correlation. Therefore, the distribution trend of all pressure coefficients in the numerical simulation was considered to be consistent with those from the measurements. The findings of this study could shed light on the concentration distribution of platoon-based vehicles and the future application of CFD simulations to estimate the concentration of pollutants along urban street canyons.

Wind Tunnel Experiment and Numerical Simulation of the Pressure Distribution on a Sedan Exterior Surface

2013 ◽  
Vol 300-301 ◽  
pp. 1027-1031
Author(s):  
Bo Yang ◽  
Li Na Huang ◽  
De Jiu Wu ◽  
Xing Jun Hu
Keyword(s):  
Numerical Simulation ◽  
Wind Tunnel ◽  
Pressure Distribution ◽  
Cfd Simulation ◽  
Wind Tunnel Experiment ◽  
Aerodynamic Noise ◽  
Computational Domain ◽  
Side View ◽  
Side Window ◽  
Near Wall

The wind tunnel measurement and numerical simulation of a 50% scaled sedan model surface pressure distribution were made in order to provide fundamental data for improving the Computational Fluid Dynamics (CFD) simulation accuracy of the aerodynamic noise related flow field around automobiles. The pressure measurement positions of the wind tunnel experiment were on the side window and the door. The wind tunnel test section speed was 30m/s at 0° yawing angle. As for the CFD simulation, the wind tunnel shape computational domain and four settings of the near wall computational mesh were made. Both the k-ω SST and the Realizable k-ε turbulence models were chosen. And three value ranges of the near wall computational mesh’s dimensionless wall distance (y+) were realized. Compared with the experimental data, the pressure coefficient (CP) simulation results showed good agreement with the measurement at the re-attaching region on the side window and the attaching region on the door. But the large CPprediction errors happened in the region of the front pillar vortex, the side view mirror wake. It was also shown that the predicted CPvalues were almost independent of the y+value, except the comparatively larger CPpredicted errors on the side window obtained by using the k-ω SST turbulent model when the y+value ranged from 4 to 7. Further unsteady CFD simulation and the exterior aerodynamic noise measurement need be carried out due to the unsteady features of the separated flows, including the front pillar vortex and the side view mirror wake.

scholarly journals Dynamic Analysis and CFD Numerical Simulation on Backpressure Filling System

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Jing Qian ◽  
J. P. Lu ◽  
S. L. Hui ◽  
Y. J. Ma ◽  
D. Y. Li
Keyword(s):  
Numerical Simulation ◽  
Cfd Simulation ◽  
Production Capacity ◽  
Mechanical Analysis ◽  
Limit Values ◽  
Filling System ◽  
Actual Operation ◽  
Working Principle ◽  
Cfd Numerical Simulation ◽  
The Relationship

A backpressure filling system is a kind of air type filling system which could be applied to power type, fine or coarse grain, or mixtures with fine and coarse components. The working principle of backpressure filling system was discussed based on fundamental hydromechanics. The research limit values of backpressure were achieved via mechanical analysis. Comparing with the exit velocity of material by theoretical analysis and numerical simulation, the CFD simulation model was confirmed and its related parameters were determined. The CFD numerical simulation shows the relationship between production capacity of packaging machine and backpressure, and the results matched actual operation of the equipment well. Combining with the demand of device capacity, the range of backpressure could be controlled at 8 kPa~11 kPa.

1821 Numerical Simulation and Wind Tunnel Experiment of Double Contra-rotating Rotors Wind Turbine

2005 ◽  
Vol 2005 (0) ◽  
pp. 278
Author(s):  
Yasushi Warisawa ◽  
Yoshitaka Takeda ◽  
Kouhei Shima ◽  
Kengo Murakami ◽  
Yuuki Hotegi ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Wind Tunnel ◽  
Wind Turbine ◽  
Wind Tunnel Experiment
Sign in / Sign up

Export Citation Format

Share Document