著者

久我 秀功 太田 健太郎 伊川 雄希 坂下 泰靖 西田 周平 溝兼 通矢 岡本 哲

出版者

マツダ株式会社

雑誌

マツダ技報 (ISSN:02880601)

巻号頁・発行日

vol.36, pp.102-106, 2019 (Released:2019-12-02)

参考文献数

1

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新型MAZDA3の開発では,CO2排出量低減技術の一環として,実際の市場環境に近い走行状態で車両全体の風流れの運動エネルギーマネジメントを行い,空気抵抗の低減とサーマルマネジメント効率化の両立を目指した。この実現にむけ,フロントグリルを通過する風を用いてラジエーターを効率的に冷却するための導風構造を設定し,無駄な風を極限まで減らした。そして,アクティブエアシャッターをラジエーターの全面に配置し,シャッター開度を6段階で制御することで,走行シーン毎にエンジンルーム内の部品温度をコントロールするとともに,排出する際に生じる風流れの運動エネルギー損失が最少となる風量にコントロールした。更に,冷却に用いた風を排出する際,車両周りの風流れの運動エネルギー損失量が最少となるように構造を作り込むことで,クラストップレベルの空気抵抗係数とCO2排出量の低減に貢献した。

著者

中島 卓司 坪倉 誠 岡田 義浩 農沢 隆秀 溝兼 通矢 土井 康明

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.80, no.818, pp.FE0301-FE0301, 2014 (Released:2014-10-25)

参考文献数

13

被引用文献数

2

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The objective of this study is to investigate aerodynamics and its generating mechanism of a road vehicle in steady-state cornering, which is the most basic cornering condition. The vehicle motion in the steady-state cornering was defined on a frame of reference fixed on the vehicle and it was divided into a rotation around a vertical axis and a sideslip. Then, aerodynamic force generated by each motion and its generating mechanism was discussed. In order to reproduce an effect of the rotational motion, a towing tank experiment was conducted to measure the fluid-dynamic force acting on a one-fifth-scale model of a sedan-type road vehicle. Assuming that the fluid-dynamic forces are expressible as a linear superposition of effects of the rotation and sideslip, first derivatives of the side force and yaw moment with respect to the yaw rate and the lateral velocity were analyzed by a multiple linear regression analysis. From the results of measurement and analysis, it was clarified that the assumption can provide good approximations of the force and the moment within a range of measurement conditions in this study. Regarding the fluid-dynamic side force, the rotation generates a centripetal force of the circular motion and the sideslip generates a force suppressing the slip motion. Regarding the fluid-dynamic yaw moment, the rotation generates a moment suppressing the rotation, and the sideslip generates a moment enhancing the vehicle's slip angle. Aerodynamics of a sedan-type road vehicle was estimated quasi-steadily by multiple regression equations with measured vehicle motion in an on-road test. From this estimation, the effects of both the rotation and the sideslip had the same order of magnitude. This result indicates that the effects of the vehicle's rotational motion have the same level of importance as the effects of the sideslip in vehicle aerodynamics in steady-state cornering.