Numerical Assessment of Side-Wind Effects on a Bus in Urban Conditions
Source abstract
Abstract
The drag coefficient is usually considered to be a constant value, which allows us to calculate the aerodynamic losses. However, at lower speeds and wind, this value could be distorted. This also applies to buses in urban environments where due to traffic, the speed is relatively low. Since the schedule of the buses is fixed, based on the driving cycle, they travel at a nominal cruising speed. This makes it possible to examine the drag losses in a quasi-steady condition. To find the magnitude of this distortion in losses, a large-eddy simulation method was used with the help of commercially available software. Symmetrical and asymmetrical flows were induced into the digital wind tunnel to assess the distribution of the forces in the cruising direction and examine the flow patterns. It was discovered that the drag forces behave differently due to the low speeds, and calculations should be performed differently compared to high-speed drag evaluations.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Aerodynamics and Fluid Dynamics Research · Wind and Air Flow Studies · Vehicle emissions and performance
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Building Services and Building Engineering, Faculty of Engineering, University of Debrecen, 4028 Debrecen, Hungary
Funding
Thematic Excellence Programme of the Ministry for Innovation and Technology
References (34)
Show source-provided references
1. An on-road investigation into the conditions experienced by a heavy goods vehicle operating within the United Kingdom10.1016/j.trd.2016.08.034 ↗
2. Diedrichs, B. (2008, January 20–24). Aerodynamic Calculations of Crosswind Stability of a High-Speed Train Using Control Volumes of Arbitrary Polyhedral Shape. Proceedings of the BBAA VI International Colloquium on Bluff Bodies Aerodynamics & Applications, Milano, Italy.
3. Rolén, C., Rung, T., and Wu, D. (2004, January 24–28). Computational Modelling of Cross-Wind Stability of High Speed. Proceedings of the European Congress on Computational Methods in Applied Sciences and Engineering, Jyväskylä, Finland.
4. Numerical and experimental studies of train geometries subject to cross winds
5. Numerical studies on aerodynamics of high-speed railway train subjected to strong crosswind10.1177/1687814019887270 ↗
6. A drag coefficient for application to the WLTP driving cycle10.1177/0954407017704784 ↗
7. Torres, P., Le Clainche, S., and Vinuesa, R. (2021). On the experimental, numerical and data-driven methods to study urban flows. Energies, 14.10.3390/en14051310 ↗
8. Investigation of the Reynolds number independence of cavity flow in 2D street canyons by wind tunnel experiments and numerical simulations10.1016/j.buildenv.2021.107965 ↗
9. Interactions between extreme climate and urban morphology: Investigating the evolution of extreme wind speeds from mesoscale to microscale10.1016/j.uclim.2019.100544 ↗
10. Stable Stratification Effects on Flow and Pollutant Dispersion in Boundary Layers Entering a Generic Urban Environment10.1007/s10546-015-0124-7 ↗
11. Dadioti, R., and Rees, S.J. (2015, January 7–9). Validation of open source cfd applied to building external flows. Proceedings of the 14th International Conference IBPSA—Building Simulation 2015 (BS 2015), Hyderabad, India.10.26868/25222708.2015.2253 ↗
12. Cross Comparisons of CFD Results of Wind Environment at Pedestrian Level around a High-Rise Building and within a Building Complex10.3130/jaabe.3.63 ↗
13. Wieser, D., Nayeri, C.N., and Paschereit, C.O. (2020). Wake structures and surface patterns of the drivaer notchback car model under side wind conditions. Energies, 13.10.3390/en13020320 ↗
14. Influence of Rotating Wheels and Moving Ground Use on the Unsteady Wake of a Small-Scale Road Vehicle10.1007/s10494-020-00180-8 ↗
15. Effect of moving ground simulation on the flow past bus models10.1016/0167-6105(86)90090-5 ↗
16. CFD investigation on wheel rotation modelling10.1016/j.jweia.2018.01.005 ↗
17. Comparison of bus driving cycles elaborated for vehicle dynamic simulation
18. Development of Bus Driving Cycle for Debrecen on the Basis of Real-traffic Data10.3311/PPtr.16109 ↗
19. Source identification of fine and coarse aerosol during smog episodes in Debrecen, Hungary10.1007/s11869-021-01008-8 ↗
20. A new solar radiation database for estimating PV performance in Europe and Africa10.1016/j.solener.2012.03.006 ↗
21. Subgrid-scale stress modelling based on the square of the velocity10.1023/A:1009995426001 ↗
22. Effects of wind loads and floating bridge motion on intercity bus lateral stability10.1016/j.jweia.2021.104589 ↗
23. Hunt, J.C.R., and Wray, P.M.A.A. Eddies, Stream, and Convergence Zones in Turbulent Flows. Proceedings of the Center for Turbulence Research, Summer Program, Available online: https://ntrs.nasa.gov/citations/19890015184.
24. Ahmed, S.R., Ramm, G., and Faltin, G. (1984). Some Salient Features of the Time-Averaged Ground Vehicle Wake, SAE Transactions.10.4271/840300 ↗
25. Drag Coefficient Determination of a Bus Model Using Reynolds Number Independence
26. Drag reduction of a bus model by passive flow canal
27. Aerodynamic Exterior Body Design of Bus
28. Modification in commercial bus model to overcome aerodynamic drag effect by using CFD analysis10.1016/j.rineng.2019.100091 ↗
29. Janna, W.S., and Schmidt, D. (2014, January 15–18). Fluid Mechanics Laboratory Experiment: Measurement of Drag on Model Vehicles. Proceedings of the 2014 American Society for Engineering Education Annual Conference & Exposition, Indianapolis, IN, USA.
30. PIV studies around a bus model10.1016/j.expthermflusci.2011.11.014 ↗
31. Numerical study of the flow around a bus-shaped body10.1115/1.1567305 ↗
32. Szodrai, F. (2020). Quantitative Analysis of Drag Reduction Methods for Blunt Shaped Automobiles. Appl. Sci., 10.10.3390/app10124313 ↗
33. Drag reduction on a three-dimensional blunt body with different rear cavities under cross-wind conditions10.1016/j.jweia.2020.104145 ↗
34. Ingram, K.C. (1978). The Wind-Averaged Drag Coefficient Applied to Heavy Goods Vehicles, The National Academies of Sciences, Engineering, and Medicine. Available online: https://trid.trb.org/view/80996.