An economical method for computation of stationary conditions in gas transport systems

Аннотация

An economic iterative method is proposed for simulating stationary conditions in complex gas transport systems of any topology. The method exploits a fast algebraic pipe model with periodic identification, which is used to adjust the model to the stationary conditions under consideration and to provide the required accuracy of calculation. The identification procedure is based on the solution of stationary hydrodynamic equations. The gas transport system is represented as a list of pipes and a list of nodes. As an initial approximation, we define gas pressures and temperatures in the nodes and thus setting boundary conditions for the stationary flow. In the global iterations of the method, the pressures and temperatures are updated to make the flow disbalance tend to zero. The method allows parallel computing on multiprocessor computers. It is implemented as a separate module in the VOLNA software. Its efficiency is demonstrated through a sample calculation for the gas transport system. A number of related issues are considered, including simulation accuracy, peculiarities in the solution of stationary equations, and the correctness of the calculation setup. The method can be used in combination with any other model of piped compressible gas.