Optimization of Trailer Boat Tail using Computational Fluid Dynamics simulations

TRANSTEX COMPOGY是交通运输行业空气动力学设备的先驱制造商和设计者。目前，该公司专注于拖车侧裙和船尾的设计和制造，以减少拖车的底部和后部阻力。利用风洞试验结果设计了船尾的初步模型。然而，改进他们的产品和最终确定它的设计需要更多的**实验结果。风洞实验的成本很高，而且无法提供船尾周围流动的所有细节。其他类型的流动可视化技术不能用来研究移动的卡车上的流动**，特别是在实际的尺度上。因此，该公司提出了利用计算流体动力学(CFD)建模**来模拟带船尾的移动卡车拖车周围的流动。致力于改进不同卡车车身的气动性能一直是汽车行业各个研究小组关注的焦点[1-3]。这项工作确定了重型车辆周围产生阻力的流动结构**，并设计了不同的附加装置来减少阻力并提高道路燃油经济性[4，5]。可以通过修改拖车的后端和操纵近尾迹来减少阻力**。船尾是可以在这方面使用的**装置[6-8]。已经进行了各种研究来研究船尾对减少拖车上的空气动力阻力的影响[9，10]。然而，关于船尾周围的流动行为，特别是在真实尺度上的信息是有限的[11]。在这项研究中，将进行一组CFD模拟来计算船尾的临界力。根据CFD结果，将评估**Transtex初步船尾的性能，并向**Transtex研发团队提供改进其产品的建议和建议。此外，这项研究的结果将被用作**船尾组件(如接头和连接)的有限元分析的输入。在加拿大，当拖车上安装减阻设施后，轨道用于在加拿大两点之间转移的燃料量可以大大减少，从而在长距离内减少高达8%的二氧化碳排放。

Transtex Composite is pioneer manufacturer and designer of aerodynamic devices for the transportation**industry. Currently, the company has focused on the design and manufacturing of trailer side skirts and boat**tails to reduce the underneath and rear drag force on trailers. The preliminary model of the boat tail is designed**using the wind tunnel test results. However, improving their product and finalizing its design need more**experimental results. The wind tunnel experiment is costly, and it cannot provide all details of flow around the**boat tail. Other types of flow visualization techniques cannot be used to study the flow over a moving truck**especially in the actual scale. Therefore, utilizing Computational Fluid Dynamics (CFD) modeling is proposed**for the company to simulate the flow around a moving truck-trailer with a boat tail. Working on the**aerodynamic improvement of different truck bodies has been the focus of various research groups in the**automotive industries [1-3]. This effort has identified drag producing flow structures around heavy vehicles**and designed different add-on devices to reduce drag and improve the road fuel economy [4,5]. The drag force**can be reduced by modifying the rear end of the trailer and manipulate the near wakes. Boat tails are the**devices that can be used in this regard [6-8]. Various studies have been conducted to investigate the effects of**boat tail on reducing aerodynamic drag on the trailer [9, 10]. However, information regarding the flow behavior**around the boat tail especially in real scale is limited [11]. In this research, a set of CFD simulations will be**conducted to calculate the critical forces on the boat tail. Base on the CFD results, the performance of the**preliminary Transtex boat tail will be evaluated, and recommendations and suggestions will be provided to the**Transtex R&D team to improve their products. Also, the results of this research will be utilized as input for**Finite Element Analysis of the boat tail components such as joints and connections. The amount of fuel which**is used by a track to transfer between two points in Canada can be reduced dramatically when the drag**reduction facilities attached to trailers and consequently CO2 emission will be cut up to 8% in long distances.