{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Control Volume Analysis\n", "\n", "## Learning outcomes\n", "\n", "* Understand the system representation of matter from a Lagrangian perspective\n", "* Learn about the conservation laws for mass, momentum and energy\n", "* Understand the concept of a control volume and how the conservation laws apply\n", "* Get comfortable with the idea of a surface normal vector.\n", "* Remind ourselves about the dot product with some Python\n", "\n", "# System Representation of Matter\n", "\n", "A system is a collection of matter that may move, flow and interact with its surroundings. You can imagine a fluid flow moving through a conduit as shown below and we somehow manage to tag a large number of Lagrangian particles in a cuboid of space and then we track those tagged particles as they move through the duct. **These tagged Lagrangian particles are a system** and they may move, flow and interact with their surroundings. As the duct's cross sectional area expands the shape of the system stretches in the *spanwise* direction and contracts in the *streamwise* direction since there are only so many particles in our system.\n", "\n", "At various moments in time we can mark the volume and boundary occupied by the system as shown in red. Note that the flow shown below is a simplified inviscid frictionless flow.\n", "\n", "