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commit 78f90f20a696741f7c3be5d57d92bc93f1cfb66e
parent 33ce29db834efa19b28dde2f3bfc92e957cc6b93
Author: miksa <milutin@popovic.xyz>
Date:   Sun, 19 Jun 2022 11:36:48 +0200

fix and add abstract

Diffstat:
Aapp_pde/abstract.tex | 17+++++++++++++++++
Mapp_pde/appendix.tex | 28++++++++++++++--------------
Mapp_pde/build/main.pdf | 0
Mapp_pde/chap1.tex | 256++++++++++++++++++++++++++++++++++++++++----------------------------------------
Mapp_pde/main.tex | 2++
Mapp_pde/preamble.tex | 2+-
6 files changed, 162 insertions(+), 143 deletions(-)

diff --git a/app_pde/abstract.tex b/app_pde/abstract.tex @@ -0,0 +1,17 @@ +\begin{abstract} + The aim of this project is to give a master student a general idea of + fluid dynamic and further combining this knowledge to model a problem + focusing on the tsunami, generated by an earthquake in the Andaman Basin + in 2004. In this regard focusing on inviscid water flow, where the mass + density of water is taken to be constant. It is qualitatively show how to + derive Euler's Equations of Motion using basic multivariable analysis. + The whole problem of modeling water waves comes around to determining the + wave profile at the surface $z = h(x,y,t)$, where the need + to introduce boundary conditions on the governing equations comes into + play. To derive model hierarchies for different regimes (e.g. shallow + water, long-wave or small amplitude) dimensional analysis and scaling of + the parameters together with asymptotic expansion becomes essential. + Asymptotic analysis gives a model for the regime of the solitary wave and + the KdV equation which is the region $\varepsilon=O\left(\delta \right)$, + a key to modeling the tsunami wave before approaching the shore. +\end{abstract} diff --git a/app_pde/appendix.tex b/app_pde/appendix.tex @@ -13,8 +13,8 @@ $b(t)$ respectively, by \begin{align} \frac{d\mathcal{I}}{dt} = \frac{\partial \mathcal{I}}{\partial t}+ - \frac{\partial \mathcal{I}}{\partial a}\frac{\partial a}{\partial t}+ - \frac{\partial \mathcal{I}}{\partial b}\frac{\partial b}{\partial t}. + \frac{\partial \mathcal{I}}{\partial b}\frac{\partial b}{\partial t}+ + \frac{\partial \mathcal{I}}{\partial a}\frac{\partial a}{\partial t}. \end{align} Which in integral representation reads \begin{align} @@ -30,11 +30,11 @@ We start off with the standard material derivative \frac{D\mathbf{u}}{Dt} = \frac{\partial \mathbf{u}}{\partial t} +(\mathbf{u}\nabla)\mathbf{u}. \end{align} -We will use Einstein's Summation Convention, where we sum over indices that -both appear at as the bottom as the top index, to rewrite the second part of -the material derivative $(\mathbf{u}\nabla)\mathbf{u}$ into +We will use Einstein's Summation Convention, where we sum over indices +appearing at the bottom and the top. To rewrite the second part of the +material derivative $(\mathbf{u}\nabla)\mathbf{u}$ into \begin{align} - (\mathbf{u}\times (\nabla \times \mathbf{u}))_k + (\mathbf{u}\times (\nabla \times \mathbf{u}))_i &= \varepsilon^{ijk}u_j(\nabla \times \mathbf{u})_k \\ &= \varepsilon^{ijk}u_j\varepsilon_{klm}\partial^l u^m\\ &=(\delta^i_l\delta^j_m-\delta^i_m\delta^j_l)u_j\partial^l u^m\\ @@ -62,24 +62,24 @@ In our case the implicit function for fixed time reads \end{align} The parametric representation is \begin{align} - \mathbf{\sigma} = \begin{pmatrix} x_1 \\ x_2 \\ h \end{pmatrix} . + \vec{\sigma} = \begin{pmatrix} x_1 \\ x_2 \\ h \end{pmatrix} . \end{align} -The middle curvature of the surface parametrized by $\mathbf{\sigma}$ is +The middle curvature of the surface parametrized by $\vec{\sigma}$ is \begin{align} \frac{1}{R} = \text{Tr}(G^{-1}B), \end{align} where $G$ and $B$ are given by \begin{align} - G_{ij} = \frac{\partial \mathbf{\sigma}}{\partial x_i} \frac{\partial - \mathbf{\sigma}}{\partial x_j}, \\ - B_{ij} = -\mathbf{N} \frac{\partial^2 \mathbf{\sigma}}{\partial + G_{ij} = \frac{\partial \vec{\sigma}}{\partial x_i} \frac{\partial + \vec{\sigma}}{\partial x_j}, \\ + B_{ij} = -\mathbf{N} \frac{\partial^2 \vec{\sigma}}{\partial x_i\partial x_j}, \end{align} where $i, j = 1, 2$ and $\mathbf{N}$ is the normal, normalized surface vector given by \begin{align} - \mathbf{N} &= \frac{\frac{\partial \mathbf{\sigma}}{\partial x_1}\times - \frac{\partial \mathbf{\sigma}}{\partial x_2}}{\|\frac{\partial \mathbf{\sigma}}{\partial x_1}\times - \frac{\partial \mathbf{\sigma}}{\partial x_2}\|} \\ + \mathbf{N} &= \frac{\frac{\partial \vec{\sigma}}{\partial x_1}\times + \frac{\partial \vec{\sigma}}{\partial x_2}}{\|\frac{\partial \vec{\sigma}}{\partial x_1}\times + \frac{\partial \vec{\sigma}}{\partial x_2}\|} \\ &= \frac{1}{\sqrt{h_x^2 + h_y^2 +1}} \begin{pmatrix} -h_x\\-h_y\\1 \end{pmatrix}. \end{align} diff --git a/app_pde/build/main.pdf b/app_pde/build/main.pdf Binary files differ. diff --git a/app_pde/chap1.tex b/app_pde/chap1.tex @@ -426,131 +426,131 @@ As a consequence the \textbf{Integrated Mass Condition} is given by \nabla_\perp \int_b^h \mathbf{u}_\perp\ dz + \underbrace{h_t - b_t}_{=d_t} = 0. \end{align} -\subsection{Energy Equation} -To derive the energy equation we start off with Euler's Equation of Motion -\begin{align} - \mathbf{u} _t + \nabla - (\frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}+\Omega) = \mathbf{u}\times - \mathbf{w}, -\end{align} -multiplying the equation with $\mathbf{u}$ we get -\begin{align} - &\mathbf{u}\mathbf{u} _t \label{eq:energy1} \\ - &+(\mathbf{u}\nabla)(\frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}+\Omega)\label{eq:energy2}\\ - &= \mathbf{u}(\mathbf{u}\times - \mathbf{w})\label{eq:energy3}. -\end{align} -The first equation given in \ref{eq:energy1} can we rewritten using inverse -product rule of differentiation -\begin{align} - \mathbf{u}\frac{\partial \mathbf{u}}{\partial t} - &= \frac{\partial - }{\partial t} (\mathbf{u}\mathbf{u}) - \frac{\partial \mathbf{u}}{\partial t} - \mathbf{u} \\ - &= \frac{\partial - }{\partial t} (\mathbf{u}\mathbf{u}) - \mathbf{u}\frac{\partial - \mathbf{u}}{\partial t}\\ - \Rightarrow\quad & \mathbf{u} \frac{\partial \mathbf{u}}{\partial t} = - \frac{1}{2}\frac{\partial }{\partial t} (\mathbf{u}\mathbf{u}). -\end{align} -Then we may add -\begin{align} - \left(\frac{1}{2} \mathbf{u}\mathbf{u}+\frac{P}{\rho} +\Omega \right) - \underbrace{(\nabla u)}_{=0} = 0, -\end{align} -to above not changing anything. Thereby getting -\begin{align} - \frac{\partial }{\partial t} \left(\frac{1}{2}\mathbf{u}\mathbf{u}\right) - +(\mathbf{u}\nabla \mathbf{u})\left( - \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho} \right) - +\left( \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho} + \Omega \right) - (\nabla \mathbf{u}) = 0. -\end{align} -Applying the product rule we can simplify -\begin{align} - \frac{\partial }{\partial t} \left(\frac{1}{2}\mathbf{u}\mathbf{u}\right) - +\nabla \left(\mathbf{u}\left(\mathbf{u}( - \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}\right) \right) = 0, -\end{align} -additionally adding $\frac{\partial \Omega}{\partial t} =0$ leads us to -\begin{align} - \underbrace{\frac{\partial }{\partial t} \left(\frac{1}{2}\mathbf{u}\mathbf{u} - +\Omega\right)}_{\text{change of total energy density}} - +\underbrace{\nabla \left(\mathbf{u}\left(\mathbf{u}( - \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}\right) -\right)}_{\text{energy flow of the velocity field}} = 0.\label{eq:energy} -\end{align} -This is called the \textbf{energy equation} and is a general result for a -inviscid and incompressible fluids, which we can apply to study water waves. -We start off with replacing $\nabla = \nabla_\perp + \frac{\partial }{\partial -z} $ and $\Omega = g z$ and multiplying by $\rho$, then our energy equation -in \ref{eq:energy} becomes -\begin{align} - \frac{\partial }{\partial t}\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho - g z\right) + \nabla_\perp\left( \mathbf{u}_\perp\left( - \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho gz \right) \right) - \frac{\partial}{\partial z} \left( w\left( - \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho g z \right) \right) = 0. -\end{align} -Integrating from bottom to top, i.e. from bed to free surface gets us to -\begin{align} - &\int_b^h\frac{\partial }{\partial t}\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho - g z\right)\ dz \label{eq:e-int1}\\ - &+ \int_b^h \nabla_\perp\left( \mathbf{u}_\perp\left( - \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho gz \right) \right)\ - dz\label{eq:e-int2}\\ - &+ \left(\frac{\partial}{\partial z} \left( w\left( - \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho g z \right) -\right)\right)\Bigg|_b^h \label{eq:e-int3} - = 0. -\end{align} -For equation \ref{eq:e-int1} we use Leibniz Rule of Integration, leaving us -with -\begin{align} - \int_b^h\frac{\partial }{\partial t}\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho - g z\right)\ dz - &= \frac{\partial }{\partial t} \int_b^h - \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho gz \ dz\\ - &+ \left( \frac{1}{2}\rho \mathbf{u}_s \mathbf{u}_s + \rho g h \right) - h_t\\ - &- \left( \frac{1}{2}\rho \mathbf{u}_b \mathbf{u}_b + \rho g b \right) - b_t -\end{align} -For equation \ref{eq:e-int2} we again take note of the Leibniz Rule of -Integration, getting -\begin{align} - \int_b^h \nabla_\perp\left( \mathbf{u}_\perp\left( - \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho gz \right) \right)\ - dz - &= \nabla_\perp \int_b^h \mathbf{u}_\perp\left( - \frac{1}{2}\rho\mathbf{u}\mathbf{u} + P + \rho g z \right) \ dz\\ - &- \left( \frac{1}{2}\rho \mathbf{u}_s\mathbf{u}_s + P + \rho g h \right) - \left( \mathbf{u}_{\perp s} \nabla_\perp \right) h\\ - &+\left( \frac{1}{2}\rho \mathbf{u}_b\mathbf{u}_b + P + \rho g b \right) - \left( \mathbf{u}_{\perp b} \nabla_\perp \right) b -\end{align} -Thereby transforming our equation into -\begin{align} - \frac{\partial }{\partial t} \underbrace{\int_b^h \frac{1}{2}\rho - \mathbf{u}\mathbf{u}+\rho g z\ dz}_{=:\mathcal{E}} - + \nabla_\perp&\underbrace{\int_b^h - \mathbf{u}_\perp\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho g z -\right)\ dz}_{:=\mathcal{F}} -+ \underbrace{P_s h_t - P_b b_t}_{:=\mathcal{P}} = 0\\ -\nonumber\\ - &\frac{\partial \mathcal{E}}{\partial t} - + \nabla_\perp \mathcal{F} + \mathcal{P} = 0, -\end{align} -where $\mathcal{E}$ represents the energy in the flow per unit horizontal -area, since we are integrating from bed to free surface. Where $\mathcal{F}$ -is the horizontal energy flux vector and lastly $\mathcal{P} = P_s h_t - -P_b b_t$ is the net energy input due to the pressure forces doing work on the -upper and lower boundaries, i.e. bottom and free surface of the fluid. -Assuming stationary rigid bottom condition and constant surface pressure, we -can set $P_s=0$, such that $\mathcal{P} =0$ leaving us with the equation -\begin{align} - \frac{\partial \mathcal{E}}{\partial t} - + \nabla_\perp \mathcal{F} = 0. -\end{align} -We note that the assumption $P_s=0$ is only possible if the coefficient of -surface tension is set to 0, which usually is not the case. +%\subsection{Energy Equation} +%To derive the energy equation we start off with Euler's Equation of Motion +%\begin{align} +% \mathbf{u} _t + \nabla +% (\frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}+\Omega) = \mathbf{u}\times +% \mathbf{w}, +%\end{align} +%multiplying the equation with $\mathbf{u}$ we get +%\begin{align} +% &\mathbf{u}\mathbf{u} _t \label{eq:energy1} \\ +% &+(\mathbf{u}\nabla)(\frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}+\Omega)\label{eq:energy2}\\ +% &= \mathbf{u}(\mathbf{u}\times +% \mathbf{w})\label{eq:energy3}. +%\end{align} +%The first equation given in \ref{eq:energy1} can we rewritten using inverse +%product rule of differentiation +%\begin{align} +% \mathbf{u}\frac{\partial \mathbf{u}}{\partial t} +% &= \frac{\partial +% }{\partial t} (\mathbf{u}\mathbf{u}) - \frac{\partial \mathbf{u}}{\partial t} +% \mathbf{u} \\ +% &= \frac{\partial +% }{\partial t} (\mathbf{u}\mathbf{u}) - \mathbf{u}\frac{\partial +% \mathbf{u}}{\partial t}\\ +% \Rightarrow\quad & \mathbf{u} \frac{\partial \mathbf{u}}{\partial t} = +% \frac{1}{2}\frac{\partial }{\partial t} (\mathbf{u}\mathbf{u}). +%\end{align} +%Then we may add +%\begin{align} +% \left(\frac{1}{2} \mathbf{u}\mathbf{u}+\frac{P}{\rho} +\Omega \right) +% \underbrace{(\nabla u)}_{=0} = 0, +%\end{align} +%to above not changing anything. Thereby getting +%\begin{align} +% \frac{\partial }{\partial t} \left(\frac{1}{2}\mathbf{u}\mathbf{u}\right) +% +(\mathbf{u}\nabla \mathbf{u})\left( +% \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho} \right) +% +\left( \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho} + \Omega \right) +% (\nabla \mathbf{u}) = 0. +%\end{align} +%Applying the product rule we can simplify +%\begin{align} +% \frac{\partial }{\partial t} \left(\frac{1}{2}\mathbf{u}\mathbf{u}\right) +% +\nabla \left(\mathbf{u}\left(\mathbf{u}( +% \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}\right) \right) = 0, +%\end{align} +%additionally adding $\frac{\partial \Omega}{\partial t} =0$ leads us to +%\begin{align} +% \underbrace{\frac{\partial }{\partial t} \left(\frac{1}{2}\mathbf{u}\mathbf{u} +% +\Omega\right)}_{\text{change of total energy density}} +% +\underbrace{\nabla \left(\mathbf{u}\left(\mathbf{u}( +% \frac{1}{2}\mathbf{u}\mathbf{u}+\frac{P}{\rho}\right) +%\right)}_{\text{energy flow of the velocity field}} = 0.\label{eq:energy} +%\end{align} +%This is called the \textbf{energy equation} and is a general result for a +%inviscid and incompressible fluids, which we can apply to study water waves. +%We start off with replacing $\nabla = \nabla_\perp + \frac{\partial }{\partial +%z} $ and $\Omega = g z$ and multiplying by $\rho$, then our energy equation +%in \ref{eq:energy} becomes +%\begin{align} +% \frac{\partial }{\partial t}\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho +% g z\right) + \nabla_\perp\left( \mathbf{u}_\perp\left( +% \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho gz \right) \right) +% \frac{\partial}{\partial z} \left( w\left( +% \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho g z \right) \right) = 0. +%\end{align} +%Integrating from bottom to top, i.e. from bed to free surface gets us to +%\begin{align} +% &\int_b^h\frac{\partial }{\partial t}\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho +% g z\right)\ dz \label{eq:e-int1}\\ +% &+ \int_b^h \nabla_\perp\left( \mathbf{u}_\perp\left( +% \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho gz \right) \right)\ +% dz\label{eq:e-int2}\\ +% &+ \left(\frac{\partial}{\partial z} \left( w\left( +% \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho g z \right) +%\right)\right)\Bigg|_b^h \label{eq:e-int3} +% = 0. +%\end{align} +%For equation \ref{eq:e-int1} we use Leibniz Rule of Integration, leaving us +%with +%\begin{align} +% \int_b^h\frac{\partial }{\partial t}\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho +% g z\right)\ dz +% &= \frac{\partial }{\partial t} \int_b^h +% \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho gz \ dz\\ +% &+ \left( \frac{1}{2}\rho \mathbf{u}_s \mathbf{u}_s + \rho g h \right) +% h_t\\ +% &- \left( \frac{1}{2}\rho \mathbf{u}_b \mathbf{u}_b + \rho g b \right) +% b_t +%\end{align} +%For equation \ref{eq:e-int2} we again take note of the Leibniz Rule of +%Integration, getting +%\begin{align} +% \int_b^h \nabla_\perp\left( \mathbf{u}_\perp\left( +% \frac{1}{2}\rho\mathbf{u}\mathbf{u}+P+\rho gz \right) \right)\ +% dz +% &= \nabla_\perp \int_b^h \mathbf{u}_\perp\left( +% \frac{1}{2}\rho\mathbf{u}\mathbf{u} + P + \rho g z \right) \ dz\\ +% &- \left( \frac{1}{2}\rho \mathbf{u}_s\mathbf{u}_s + P + \rho g h \right) +% \left( \mathbf{u}_{\perp s} \nabla_\perp \right) h\\ +% &+\left( \frac{1}{2}\rho \mathbf{u}_b\mathbf{u}_b + P + \rho g b \right) +% \left( \mathbf{u}_{\perp b} \nabla_\perp \right) b +%\end{align} +%Thereby transforming our equation into +%\begin{align} +% \frac{\partial }{\partial t} \underbrace{\int_b^h \frac{1}{2}\rho +% \mathbf{u}\mathbf{u}+\rho g z\ dz}_{=:\mathcal{E}} +% + \nabla_\perp&\underbrace{\int_b^h +% \mathbf{u}_\perp\left( \frac{1}{2}\rho\mathbf{u}\mathbf{u} + \rho g z +%\right)\ dz}_{:=\mathcal{F}} +%+ \underbrace{P_s h_t - P_b b_t}_{:=\mathcal{P}} = 0\\ +%\nonumber\\ +% &\frac{\partial \mathcal{E}}{\partial t} +% + \nabla_\perp \mathcal{F} + \mathcal{P} = 0, +%\end{align} +%where $\mathcal{E}$ represents the energy in the flow per unit horizontal +%area, since we are integrating from bed to free surface. Where $\mathcal{F}$ +%is the horizontal energy flux vector and lastly $\mathcal{P} = P_s h_t - +%P_b b_t$ is the net energy input due to the pressure forces doing work on the +%upper and lower boundaries, i.e. bottom and free surface of the fluid. +%Assuming stationary rigid bottom condition and constant surface pressure, we +%can set $P_s=0$, such that $\mathcal{P} =0$ leaving us with the equation +%\begin{align} +% \frac{\partial \mathcal{E}}{\partial t} +% + \nabla_\perp \mathcal{F} = 0. +%\end{align} +%We note that the assumption $P_s=0$ is only possible if the coefficient of +%surface tension is set to 0, which usually is not the case. diff --git a/app_pde/main.tex b/app_pde/main.tex @@ -6,6 +6,8 @@ \begin{document} \maketitle + +\include{./abstract.tex} \tableofcontents \include{./chap1.tex} diff --git a/app_pde/preamble.tex b/app_pde/preamble.tex @@ -100,6 +100,6 @@ \title{University of Vienna\\ \vspace{1cm}Seminar:\\Applied PDE Seminar\\ \vspace{0.5cm} -Mathematical Modeling of Some Water-Waves +Mathematical Modeling of Water-Wave Problems } \author{Milutin Popovic}