diff --git a/uni/mmme/2047_thermodynamics_and_fluid_dynamics/dimensional_analysis.md b/uni/mmme/2047_thermodynamics_and_fluid_dynamics/dimensional_analysis.md index 47caf66..9851ea0 100755 --- a/uni/mmme/2047_thermodynamics_and_fluid_dynamics/dimensional_analysis.md +++ b/uni/mmme/2047_thermodynamics_and_fluid_dynamics/dimensional_analysis.md @@ -175,7 +175,7 @@ When $\text{Ma} > 0.3$, the flow should be considered compressible. # Nondimensional Momentum Equation (From Navier-Stokes) -$$\frac{\del \pmb{V*}}{\del t*} + \pmb{V*} \cdot (\Del* \pmb{V*} = -\Del* p* + \frac{1}{\text{Re}}\Del*^2\pmb{V*}$$ +$$\frac{\delta \pmb{V^*}}{\delta t^*} + \pmb{V^*} \cdot (\nabla^* \pmb{V^*}) = -\nabla^* p^* + \frac{1}{\text{Re}}\nabla^{*2}\pmb{V^*}$$ Therefore for large values of Reynolds number, the viscous forces become negligible. @@ -185,7 +185,7 @@ An airfoil model and prototype are geometrically similar, with $1:\alpha$ length - $x_m = \frac{x_p}{\alpha}$, $y_m = \frac{y_p}{\alpha}$ - $u_m$ at $(x_m, y_m)$ must have the same direction at $u_p$ at $(x_p, y_p)$ -- $\frac{u_p}{u_m} = \Beta$ is constant at homologous points +- $\frac{u_p}{u_m} = \beta$ is constant at homologous points ![](./images/vimscrot-2023-02-06T09:46:38,665212789+00:00.png)