Comparison of pressure-velocity coupling schemes for 2D flow problems

Abstract

Predicting accurately the behaviour of fluids, whether it is water, air, petrol or blood, is of crucial importance in numerous fields such as engineering and medicine. The most widely used way to solve fluid flow problems is to use pressure-correction methods based on algorithms such as SIMPLE (Semi Implicit Method for Pressure Linked Equations), SIMPLER (Revised), SIMPLEC (Consistent) or PISO (Pressure Implicit with Splitting of Operators). FLUENT and STAR CD are the main software capable of calculating and plotting fluid flows for specified problems, using pressure-correction methods. Nevertheless these programs, intended for commercial use, are not ‘user friendly’ and are therefore very difficult to use efficiently; furthermore once the program finds the answer it is not easy to understand how it got to it. The aim of this research is to implement the algorithms SIMPLE, SIMPLER, SIMPLEC and PISO into Matlab in order to create a ‘user-friendly’ program that a novice user can use straightforwardly and efficiently, whilst at the same time understanding what calculations the computer performs between the specification of the problem and the answers. Using this code we will then solve 2D flow problems with the different algorithms and compare their different performances (computer time, convergence and accuracy). This research should result in a program which is user-friendly and which uses a new improved algorithm (combination of the above or new altogether) that performs better than the existing ones, thereafter reducing computational times and improving accuracy.