Unsteady modeling of Pig Operations in Natural Gas Pipeline

• 1、Department of mechanics ,Liaoning Technical University

Abstract：In the production and management of the natural gas pipelines, the pigging are widely used to remove the condense and the gas hydrates. At present, the data of the pigging mobile modeling is not much ,the existing modeling of the pigging operation are mostly created on the steady state or quasi-steady state, however, in fact ,the process of the cleaning the pipelines is not steady. therefore these existing modeling is applied limitedly, selecting the best pig, estimating its speed and required driving pressure, often involves some guesswork on experience. Hence, it is necessary to deeply study the theory of the pigging mobile modeling. In the paper, the pigging mobile modeling under the unsteady state condition is introduced. In this modeling To obtain the unsteady gas pressure, equations of mass, momentum, energy, state of gas are solved simultaneously by the method of characteristics (MOC) on computer program; The Runge-Kutta method is used for solving the momentum equations of gas to get the initial values of the above differential equations and dynamic equation of the pig in order to the unsteady state model of pigging.

Keywords： gas pipeline pigging mobile modeling velocity