Aerospace Engineering » Aerospace Engineering http://www.aerospace.me Aerospace engineering is the branch of engineering behind the design, construction and science of aircraft and spacecraft Wed, 01 Sep 2010 03:56:11 +0000 en hourly 1 http://wordpress.org/?v=3.2.1 Thesis Students http://www.aerospace.me/thesis-students/ http://www.aerospace.me/thesis-students/#comments Wed, 01 Sep 2010 00:17:52 +0000 admin http://www.aerospace.me/press/52 If you would like to publish your on this site, or would like a blog space
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]]> http://www.aerospace.me/thesis-students/feed/ 0 Reynolds number http://www.aerospace.me/reynolds-number/ http://www.aerospace.me/reynolds-number/#comments Wed, 18 Aug 2010 16:58:08 +0000 admin http://aerospace.me/?p=34 In mechanics and , the is a measure of the ratio of inertial forces (vsρ) to viscous forces (μ/L) and, consequently, it quantifies the relative importance of these two types of forces for given flow conditions.

\mathit{Re} = \frac{\mbox{Dynamic pressure}}{\mbox{Shearing stress}} = {\rho v_{s}^2/D \over \mu v_{s}/D^2} = {\rho v_{s} D\over \mu} = {v_{s} D\over \nu}

It is the most important dimensionless in fluid and is used, usually along with other dimensionless numbers, to provide a criterion for determining dynamic similitude. When two geometrically similar flow patterns, in perhaps different fluids with possibly different flow rates, have the same values for the relevant dimensionless numbers, they are said to be dynamically similar, and will have similar flow geometry.

]]> http://www.aerospace.me/reynolds-number/feed/ 0 The Navier–Stokes equations http://www.aerospace.me/the-navier%e2%80%93stokes-equations/ http://www.aerospace.me/the-navier%e2%80%93stokes-equations/#comments Sat, 24 Jul 2010 14:11:02 +0000 admin http://aerospace.me/?p=17 Named after Claude-Louis and George Gabriel , describe the motion of viscous substances such as liquids and gases. These equations arise from applying Newton's second law to fluid motion, together with the assumption that the fluid stress is the sum of a diffusing viscous term (proportional to the gradient of velocity), plus a pressure term.

\rho \left(\frac{\partial u}{\partial t} + u \frac{\partial u}{\partial x} + v \frac{\partial u}{\partial y}+ w \frac{\partial u}{\partial z}\right) = -\frac{\partial p}{\partial x} + \mu \left(\frac{\partial^2 u}{\partial x^2} + \frac{\partial^2 u}{\partial y^2} + \frac{\partial^2 u}{\partial z^2}\right) + \rho g_x

\rho \left(\frac{\partial v}{\partial t} + u \frac{\partial v}{\partial x} + v \frac{\partial v}{\partial y}+ w \frac{\partial v}{\partial z}\right) = -\frac{\partial p}{\partial y} + \mu \left(\frac{\partial^2 v}{\partial x^2} + \frac{\partial^2 v}{\partial y^2} + \frac{\partial^2 v}{\partial z^2}\right) + \rho g_y

\rho \left(\frac{\partial w}{\partial t} + u \frac{\partial w}{\partial x} + v \frac{\partial w}{\partial y}+ w \frac{\partial w}{\partial z}\right) = -\frac{\partial p}{\partial z} + \mu \left(\frac{\partial^2 w}{\partial x^2} + \frac{\partial^2 w}{\partial y^2} + \frac{\partial^2 w}{\partial z^2}\right) + \rho g_z

]]> http://www.aerospace.me/the-navier%e2%80%93stokes-equations/feed/ 0 Aerospace engineering http://www.aerospace.me/aerospace-engineering/ http://www.aerospace.me/aerospace-engineering/#comments Fri, 23 Jul 2010 20:01:28 +0000 admin http://aerospace.me/?p=14 engineering is the branch of engineering behind the design, construction and science of aircraft and spacecraft

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