1. ABSTRACT
Modeling and simulation of natural gas supply pipeline network were investigated. Mathematical
models describing continuity, mass and energy equations were developed for pipeline network
and simulated using Comsol Multiphysics Software, in order to simulate the flow of fluid
through a pipe and 90 degree elbow. In simulating the models specific data of real life pipeline
network were adapted in the study. The models where then applied to a natural gas transmission
facility managed by Above Ground Installation (AGI). The flow was first characterized using the
Reynolds number which indicates turbulent flow, and from the literature Natural gas had been
known to be incompressible fluid, the viscosity was also assumed to be constant thus Newtonian
fluid flow. The generalized developed model was reduced to compressible, Newtonian turbulent
flow model. The incompressible turbulent fluid flow model was first applied to a pipe segment of
length 3550mm and 35.5mm diameter to determine the velocity when it is fully developed
(5.73m/s). The second stage of the simulation involves pipe dimensions to 200mm pipe length
with a diameter of 35.5mm and a 90 degree elbow. The simulated results showed that the
velocity decreased along the straight pipe segment but suddenly increased at the 90 degree
elbow. The pressure dropped along the straight segment, but increased at the 90 degree elbow.
The variation of the turbulent kinetic energy, dissipation rate and turbulent dynamic viscosity
were also considered in this work and was seen to be very significant. The model result were
compared with work done in the literature was found to in good agreement.
Keyword: fluid flow in pipe modeling, finite element method, comsol multiphysics