Experimental investigations of the aerodynamics of high performance bicycle downtubes and wheels

赛车的设计是一个竞争非常激烈的市场，以前一直依赖于一种主要基于设计师的经验和直觉的特别设计方法。与游泳和高尔夫等其他竞技运动类似，随着设计师、教练和运动员试图获得竞争优势，对新自行车概念进行严格的分析和实验科学的应用正成为设计方法中越来越重要的部分。对高性能赛车的需求并不局限于职业和奥运会运动员。普通骑行消费者的要求越来越高，这导致赛车市场的价值大幅增加，并出现了一批新的制造商，如知名的加拿大公司Cervélo。 这项拟议研究的目的是调查与自行车部件相关的独特而复杂的流动物理。这些流动的独特性的两个关键因素是低雷诺数，以及由于国际自行车联合会(UCI)的限制而在自行车设计中使用的典型的短而粗的几何形状。因此，目标是开发基础知识，使空气动力自行车的设计能够进行新的创新。因此，自行车部件将在多伦多大学航空航天研究所(UTIAS)的风洞中进行测试，并将基于通过称重传感器进行的全球力测量和使用粒子图像测速仪(PIV)的详细流场测量来评估其性能。这些实验将由工业合作伙伴Kevin Quan Studios(KQS)的CFD计算提供支持。这项研究的结果有望为改进自行车设计提供独特的物理见解。

The design of racing bicycles is a very competitive market that has relied previously on an ad hoc design approach primarily based on the designer's experience and intuition. Similar to other competitive sports, such as swimming and golf, the application of rigorous analytical and experimental science towards new bicycle concepts is becoming an increasingly important part of the design methodology as designers, coaches and athletes attempt to gain competitive advantages. The appetite for high performance racing bicycles is not restricted to professional and Olympic athletes. The average cyclist consumer is becoming more and more demanding, which has resulted in a large increase in the value of the market for racing bicycles and the emergence of a number of new manufacturers, such as the well-known Canadian company Cervélo. The aim of the proposed research is to investigate the unique and complex flow physics associated with bicycle components. Two of the key factors contributing to the uniqueness of these flows are the low Reynolds number, and characteristically short and stubby geometries used in bicycle design due to constraints imposed by the Union Cycliste Internationale (UCI). The goal is thus to develop fundamental knowledge needed to enable new innovations in the design of aerodynamic bicycles. Therefore, bicycle components will be tested in the wind tunnels at the University of Toronto Institute for Aerospace Studies (UTIAS), and their performance will be assessed based on global force measurement via a load cell and detailed flow field measurements using particle image velocimetry (PIV). The experiments will be supported by CFD computation by the industrial partner, Kevin Quan Studios (KQS). The outcomes of this research are expected to provide unique physical insights to improve bicycle designs.