Implementation and evaluation of NeqSim as property generator for multiphase flow simulation
Abstract
Multiphase flow transport is currently one of the key technologies in the development of future oil and gas fields. However, the complex nature of multiphase flow behaviour poses various challenges, and calculation methods have traditionally been relatively unreliable, sometimes balancing between art and science. As multiphase flow transport and the technologies accompanying are ever developing, more accurate models will be essential to predict the phase behaviour of oil, gas, water and chemicals. This study emphasises on developing a simulation tool named NeqSim as a fluid property generator for multiphase flow simulation. NeqSim has the benefit of having the CPA-EoS included, one of the most promising and accurate models for calculation of complex phase behaviour.The most used industrial simulation tool used for multiphase flow design today is OLGA. In the present study, the property table structure used in OLGA has been reviewed and analysed. It is the purpose of this work to develop NeqSim so that it can produce the same table structure, and be used as a valid property generator for OLGA. An object orientated approach is used in NeqSim, where the method of implementing the fluid property calculations is done with the Java programming language. Two different formats for the property table files were developed in order to obtain flexibility, and property tables generated with NeqSim were used in both two phase simulations and three phase simulations. Although no experimental results were conducted, a comparison with flow simulations made with tables created by the established property generator PVTsim provided for the verdict that NeqSim is a convincing fit as a property generator for multiphase flow simulation in OLGA.