Pipeline simulation techniques

The paper deals with different pipeline models and their simulation. First, a nonlinear distributed parameters model is derived, which is then linearised and its transfer function is obtained by a Laplace transformation and corresponding initial and boundary conditions. The pipeline is represented as a two-port system. Four representations are presented and two of them — the hybrid ones which are used in practice-are studied further. They involve three different transcendent transfer functions which are then approximated by rational transfer functions using a Padé approximation. The derived models describe the pipeline as a lumped parameter system. Due to the approximation of the high frequency gain, the derived models are only valid for a class of models — namely well damped pipelines. The derived models were comparatively verified on the basis of the measurements on a real pipeline.