“…However, as we move from classical to renewable energy sources in which we may use the gas pipelines to deal with flexibility from volatile energy creation, the need for fast transient simulation will increase. In recent years, research on natural gas networks focuses on a variety of topics: transient simulations [26,27,39,14,17], optimization and control [37,45,18], time splitting schemes for solving the parabolic flow equations [44], discretization methods [8,28], and model sensitivity [6] to mention a few. It is obvious that efficient simulation techniques are needed both for design and for control.…”