休旅車空氣動力數值模擬分析

Numerical Analysis Aerodynamic Drag of a Sport Utility Vehicle

蔡武雄

空氣動力分析 ； 計算流體力學 ； 空氣阻力 ； Aerodynamic ； Computational Fluid Dynamic(CFD) ； Drag

臺北科技大學車輛工程系所學位論文

2014年

碩士

蔡國隆

繁體中文

車輛空氣動力在多年來的研究中，主要是應用於賽車、轎車及近年來逐漸受到重視的卡車，而鮮少有對於休旅車(Sport utility vehicle)的研究。近十年以來，休旅車越來越受到消費者的歡迎，世界各大車廠已將休旅車視為其銷售主力之一。休旅車主要具有旅行車的舒適性與貨卡車的動力及越野能力，並且兼具多項優點的背後，犧牲的是車輛的油耗，另外傳統的休旅車因為具有越野能力，採用高底盤及高車身的設計，風阻係數偏大，使得休旅車的油耗遠比轎車高出許多。所以本研究主要重點在於利用逆向工程技術用於自行設計1:5 SUV車輛模型，進行一系列的計算流體力學模擬探討，主要探討車輛在各雷諾數、距地高度、轉向角度及考慮地板與輪胎效應之狀態下的各流場狀態，將車身表面之壓力係數、尾流流動的趨勢及阻力係數…等進行一系列之討論。

Aerodynamics of vehicle were focused on racing cars, sedans and truck in this years. The SUV (Sport utility vehicle) research are very rare. In recent decades, SUV are more popular for the consumers and SUV become the main product in the world’s major automakers. SUV have the comfort of the wagon and power of the trucks. But in many advantages is need to sacrifice the fuel consumption. The traditional SUV with off-road capability are using high chassis and high body design. The drag coefficient is more bigger than sedans. This study is focus on using the reverse engineering techniques from the self-design 1:5 SUV model and carry on a series of the CFD simulation. Discusses Re, height from the ground, yaw angle, floor effect and tire effect. Using pressure coefficient, wake flow and drag coefficient to discuss the flow effect around the vehicle.

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