翻訳と辞書 Words near each other ・ "O" Is for Outlaw ・ "O"-Jung.Ban.Hap. ・ "Ode-to-Napoleon" hexachord ・ "Oh Yeah!" Live ・ "Our Contemporary" regional art exhibition (Leningrad, 1975) ・ "P" Is for Peril ・ "Pimpernel" Smith ・ "Polish death camp" controversy ・ "Pro knigi" ("About books") ・ "Prosopa" Greek Television Awards ・ "Pussy Cats" Starring the Walkmen ・ "Q" Is for Quarry ・ "R" Is for Ricochet ・ "R" The King (2016 film) ・ "Rags" Ragland ・ ! (album) ・ ! (disambiguation) ・ !! ・ !!! ・ !!! (album) ・ !!Destroy-Oh-Boy!! ・ !Action Pact! ・ !Arriba! La Pachanga ・ !Hero ・ !Hero (album) ・ !Kung language ・ !Oka Tokat ・ !PAUS3 ・ !T.O.O.H.! ・ !Women Art Revolution Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Sears-Haack body ： ウィキペディア英語版 Sears–Haack body The Sears–Haack body is the shape with the lowest theoretical wave drag in supersonic flow, for a given body length and given volume. The mathematical derivation assumes small-disturbance (linearized) supersonic flow, which is governed by the Prandtl-Glauert equation. The derivation and shape were published independently by two separate researchers: Wolfgang Haack in 1941 and later by William Sears in 1947.〔 〕 The theory indicates that the wave drag scales as the square of the second derivative of the area distribution, $D\_\backslash text\; \backslash sim\; (S\text{'}\text{'}(x))^2$ (see full expression below), so for low wave drag it's necessary that $S(x)$ be smooth. Thus, the Sears–Haack body is pointed at each end and grows smoothly to a maximum and then decreases smoothly toward the second point. ==Useful Formulas== The cross sectional area of a Sears–Haack Body is: :$S(x)\; =\; \backslash frac\; ()^\; =\; \backslash pi\; R\_^2()^$ The volume of a Sears–Haack Body is: :$V\; =\; \backslash frac\; R\_^2\; L$ The radius of a Sears–Haack Body is: :$r(x)\; =\; R\_()^$ The derivative (slope) is: :$r\text{'}(x)\; =\; 3R\_()^\; (1-2x)$ The second derivative is: :$r\text{'}\text{'}(x)\; =\; -3R\_\backslash \backslash \}$ where: ''x'' is the ratio of the distance from the nose to the whole body length. This is always between 0 and 1. ''r'' is the local radius $R\_$ is the radius at its maximum (occurs at center of the shape) ''V'' is the volume ''L'' is the length $\backslash rho$ is the density of the fluid ''U'' is the velocity From Slender-body theory: :$D\_\backslash text\; =\; -\; \backslash frac\; \backslash rho\; U^2\; \backslash int\_0^\backslash ell\; \backslash int\_0^\backslash ell\; S\text{'}\text{'}(x\_1)\; S\text{'}\text{'}(x\_2)\; \backslash ln\; |x\_1-x\_2|\; \backslash mathrmx\_1\; \backslash mathrmx\_2$ alternatively: :$D\_\backslash text\; =\; -\; \backslash frac\; \backslash rho\; U^2\; \backslash int\_0^\backslash ell\; S\text{'}\text{'}(x)\; \backslash mathrmx\; \backslash int\_0^x\; S\text{'}\text{'}(x\_1)\; \backslash ln\; (x-x\_1)\; \backslash mathrmx\_1$ These formulas may be combined to get the following: :$D\_\backslash text\; =\; \backslash frac\; \backslash rho\; U^2\; =\; \backslash frac\; \backslash rho\; U^2$ :$C\_\; =\; \backslash frac$ 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「Sears–Haack body」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.