Updated readme

Author: hkjeldsberg

README.md

@@ -1,2 +1,35 @@
-# FlowInstabilities
-SSCP 2021 Project - Group 6 - Flow instabilities in Aneurysms
+## FlowInstabilities
+
+<p align="center">
+    <img src="https://i.ibb.co/ZGWQSp8/models.png" width="840 height="480" alt="Models used in code"/>
+</p>
+<p align="center">
+    The five arterial models use to compute flow perturbation and corresponding eigenvalues.
+</p>
+
+Description
+-----------
+FlowInstabilities is a framework for studying flow instabilities through the Reynolds-Orr method. 
+Initially, the Navier-Stokes equations are solved to find the base flow in the given geometry, before a eigenvalue problem is defined and solved for the perturbed flow and its corresponding eigenvalues.
+In the current implementation the method is applied to cerebral arteries, to understand the risk of rupture in [cerebral aneurysms](https://en.wikipedia.org/wiki/Intracranial_aneurysm), including a simple cylinder case to demonstrate Poiseuille flow.
+ The code is also applicable to other geometries in order to understand flow instabilities. 
+ 
+Installation
+------------
+
+For reference, FlowInstabilities requires the following dependencies: FEniCS >= 2018.1.0, Numpy >= 1.13 and SLEPc4Py >= 3.0.0.
+To run the cylinder case (Poiseuille flow) there is an additional dependency: mshr >= 2018.  
+If you are on Windows, macOS or Linux you can install all the general dependencies through anaconda.
+
+Usage
+-----
+Inside a FEniCS/SLEPc environment, execute the following command to run the main script for case 0, kinematic viscosity of 0.1 and a pressure drop of 5 mmHg
+
+        python find_pertubation.py --case 0 --nu 0.1 --delta_p 5
+
+The results will be located in the `Eigenmodes` folder.
+Alternatively, you can solve explicitly for the base flow by executing the following command.
+
+        python find_baseflow.py
+
+The results will now be saved in the `Baseflow` folder.