Analysis of numerical methods to solve one-dimensional fluid-dynamic governing equations under impulsive flow in tapered ducts

A comparative study of different schemes to solve one-dimensional (1-D) gas flow equations in tapered pipes was conducted in this paper. The total variation diminishing schemes, flux corrected transport techniques or the innovative space–time conservation element and solution element method have been contrasted with experimental data. The experimental results were obtained with an impulsive flow test rig, where isolated pressure pulses can be generated in order to study the flow-dynamic behaviour of different components, including tapered pipes. The results of the different schemes were compared to the experimental data and a fairly good agreement was achieved when high-resolution schemes were used but with a considerable increment of computational effort. A mass conservation study through the tapered ducts with impulsive flow was also carried out, which demonstrated that it is not the resolution level of the scheme but the governing equations arrangement that has decisive importance in mass conservation.