翻訳と辞書 Words near each other ・ Searsia (plant) ・ Searsia koefoedi ・ Searsia lucida ・ Searsia pyroides ・ Searsioides ・ Searsmont, Maine ・ Searson Wigginton ・ Searsport ・ Searsport (CDP), Maine ・ Searsport Terminal ・ Searsport, Maine ・ Searsport–Loring Pipeline ・ Searston ・ Searston Beds Formation ・ Searsville Dam ・ Sears–Haack body ・ Searunner 25 ・ Searunner 31 ・ Searunner 37 ・ Searunner 40 ・ Seas (disambiguation) ・ Seas Beneath ・ Seas of Blood ・ Seas west of Scotland ・ SEAS-NVE Park ・ Seasaar ・ Seasalter ・ Seasar ・ Seasat ・ Seascale 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.