Cross Winds and Transients: Reality, Simulation and Effects
Cross Winds and Transients: Reality, Simulation and Effects
复制标题
侧风和瞬变：现实、模拟和效果
DOI：
10.4271/2011-01-0172
复制
发表时间：
2011
期刊：
影响因子：
--
通讯作者：
D. Sims
中科院分区：
文献类型：
--
作者：
D. Sims
这份文件提供了一份已发表的
在2010年SAE世界大会上获得相同的称号。
道路上的车辆遇到不稳定流，
自然风中的湍流，由于不稳定的尾流，
其他车辆，由于穿越
路边障碍物的静止尾迹。这最后一项是
最大的意义。
各种工作有关的表征，模拟和
道路湍流的影响进行了比较，
湍流光谱，以突出差异和相似性。
不同的作品涉及不同的几何形状，
不同的方法来模拟侧风瞬变，
这些作品一起提供了最重要的指导，
不稳定的方面。
道路瞬态包括一系列长度尺度，
几个数量级，但最重要的尺度是
在2-20车辆长度范围内。存在显著
该地区道路上的不稳定程度，
相应的频率足够高，
需要进行动态测试，以正确确定车辆
反应这些尺度的波动会产生显著的
非定常载荷（空气动力学导纳通常为0.6-1.4）
并且相应的频率会对
车辆动力学
产生的规模大于规模的车辆是
对于被动网格和主动湍流不切实际
优选发电系统。这些可以分为
基于升力和阻力的装置。基于升降机的设备提供更好的
控制湍流，但只能重现
2-20车辆长度范围内的较小比例尺。不同
还讨论了移动模型方法。CFD提供真实的
通过其允许任意时变的能力，
边界条件
This paper provides a published counterpart to the address of
the same title at the 2010 SAE World Congress.
A vehicle on the road encounters an unsteady flow due to
turbulence in the natural wind, due to the unsteady wakes of
other vehicles and as a result of traversing through the
stationary wakes of road side obstacles. This last term is of
greatest significance.
Various works related to the characterization, simulation and
effects of on-road turbulence are compared together on the
turbulence spectrum to highlight differences and similarities.
The different works involve different geometries and
different approaches to simulating cross wind transients but
together these works provide guidance on the most important
aspects of the unsteadiness.
On-road transients include a range of length scales spanning
several orders of magnitude but the most important scales are
in the in the 2-20 vehicle length range. There are significant
levels of unsteadiness experienced on-road in this region and
the corresponding frequencies are high enough that a
dynamic test is required to correctly determine the vehicle
response. Fluctuations at these scales generate significant
unsteady loads (aerodynamic admittance typically 0.6-1.4)
and the corresponding frequencies can adversely affect
vehicle dynamics.
The generation of scales larger than the scale of the vehicle is
impractical with passive grids and so active turbulence
generation systems are preferred. These can be classified into
lift and drag-based devices. Lift-based devices provide better
control of the turbulence but can only just reproduce the
smaller scales in the 2-20 vehicle length range. Different
moving model approaches are also discussed. CFD offers real
advantages through its ability to allow arbitrary time-varying
boundary conditions.