Non-Linear Modelling of a Geothermal Steam Pipe Network

Abstract

Recent work on developing a non-linear model for a geothermal pipe network system is presented in this paper. Previous methods of modelling are reviewed. Using the mass and energy balance at each node and loop of a pipe network, a non-linear equation set can be established. The equation set is formulated from a conceptual model of the pipe network, which is composed of steam wells and connected pipelines. The well characteristics curves, pipeline frictional characteristic and the different combinations of the connected components all contribute to the pressure and mass flow rate distributions in the system. Some recent numerical experiments on the non-linear model are compared with Italian experience. The results converged satisfactorily. Using this model, the user can change the connection and the characteristic of each individual demand in a network and chose a desired manifold pressure; the simulator will then calculate the balanced mass flow rate and pressure distribution along the defined pipe network.