翻訳と辞書 |
Wave drag
In aeronautics, wave drag is a component of the aerodynamic drag on aircraft wings and fuselage, propeller blade tips and projectiles moving at transonic and supersonic speeds, due to the presence of shock waves. Wave drag is independent of viscous effects,〔Clancy, L.J. (1975), ''Aerodynamics'', Section 11.7〕 and tends to present itself as a sudden and dramatic increase in drag as the vehicle increases speed. It is the rise of wave drag that leads to the concept of a sound barrier. == Overview ==
Wave drag is best described as pressure drag due to compressibility effects. It is often caused by the formation of shock waves around a body, although it exists even if shock waves are not present. Shock waves create a considerable amount of drag, which can result in extreme drag on the body. Although shock waves are typically associated with supersonic flow, they can form at subsonic aircraft speeds on areas of the body where local airflow accelerates to sonic speed. The effect is typically seen on aircraft at transonic speeds (about Mach 0.8), but it is possible to notice the problem at any speed over that of the critical Mach of that aircraft. It is so pronounced that, prior to 1947, it was thought that aircraft engines would not be powerful enough to overcome the enhanced drag or that the aircraft would be at risk of breaking up in midflight. It led to the concept of a ''sound barrier''.
抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Wave drag」の詳細全文を読む
スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|