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研究生: 阮氏如瓊
Nguyen Thi Nhu Quynh
論文名稱: 針對自行車騎士模型風洞數據之統計分析
STATISTICAL ANALYSIS OF WIND TUNNEL DATA FOR CYCLIST MODEL
指導教授: 苗君易
Miau, Jiun-Jih
學位類別: 碩士
Master
系所名稱: 工學院 - 航空太空工程學系
Department of Aeronautics & Astronautics
論文出版年: 2022
畢業學年度: 110
語文別: 英文
論文頁數: 77
外文關鍵詞: Skewness, Kutorsis, Cyclist
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  • The interpretation of flow structures over a cyclist is very important for studying the phenomena around the body so that the drag force can be thoroughly investigated, thus improving the performance of racing cyclist. In this study, the analysis of statistical characteristics has been brought into consideration, along with the real-time pressure coefficients. In details, the calculation of the skewness and kurtosis of pressure coefficients at each point situated at different positions of the cyclist body has been conducted with respect to Reynolds number to understand the origination and development of the flow regime. The relation between a vortical structure and kurtosis has been observed due to the fact that there is a connection between kurtosis and high fluctuations in pressure or velocity. The CFD results on separation lines running sidelong and on the back of the model have been compared and linked with these characteristics. Large value of kurtosis is also found near both sides of the pelvis where spiral foci exist, which can be seen through the real-time signals of pressure coefficients. Probability distribution function also suggests the status of pressure field as well as velocity field, thus somewhat helps provide some ideas on the flow structures at concerned locations.
    Keywords: Skewness, Kutorsis, Cyclist.

    ABSTRACT I ACKNOWLEDGEMENT VII TABLE OF CONTENTS VIII LIST OF FIGURES X NOMENCLATURE XVII CHAPTER I INTRODUCTION 1 1.1 Overview of Research 1 1.2 Motivation of Study 4 1.3 Thesis Outline 4 CHAPTER II LITERATURE REVIEW 6 CHAPTER III METHODOLOGY 19 3.1 Probability distribution function 19 3.2 Skewness and kurtosis 20 3.3 Data processing 23 CHAPTER IV RESULTS AND DISCUSSION 25 4.1 Analysis of the points on the back 25 4.2 Analysis of the points on the hip 37 4.3 Analysis of the points on the waist 44 4.4 Analysis of the points on the leg 50 4.5 Analysis of the points on the arm 66 CHAPTER V CONCLUSION AND SUGGESTION 71 REFERENCES 73

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