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In fluid dynamics, stagnation pressure (or pitot pressure) is the static pressure at a stagnation point in a fluid flow.〔Clancy, L.J., ''Aerodynamics'', Section 3.5〕 At a stagnation point the fluid velocity is zero and all kinetic energy has been converted into pressure energy (isentropically). Stagnation pressure is equal to the sum of the free-stream dynamic pressure and free-stream static pressure.〔(Stagnation Pressure ) at Eric Weisstein's World of Physics (Wolfram Research)〕 Stagnation pressure is sometimes referred to as pitot pressure because it is measured using a pitot tube. ==Magnitude== The magnitude of stagnation pressure can be derived from a simplified form of Bernoulli Equation.〔(Equation 4 ), Bernoulli Equation - The Engineering Toolbox〕〔 For incompressible flow, : where: : is the stagnation pressure : is the fluid density : is the velocity of fluid : is the static pressure at any point. At a stagnation point, the velocity of the fluid is zero. If the gravity head of the fluid at a particular point in a fluid flow is zero, then the stagnation pressure at that particular point is equal to total pressure.〔 However, in general total pressure differs from stagnation pressure in that total pressure equals the sum of stagnation pressure and gravity head. : In compressible flow the stagnation pressure is equal to total pressure only if the fluid entering the stagnation point is brought to rest isentropically.〔Clancy, L.J. ''Aerodynamics'', Section 3.12〕 For many purposes in compressible flow, the stagnation enthalpy or stagnation temperature plays a role similar to the stagnation pressure in incompressible flow. 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「stagnation pressure」の詳細全文を読む スポンサード リンク
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