One-dimensional (1-D) modelling codes are now commonplace in engine simulation programs. Thermodynamic analysis associated with the unsteady gas flow through engine ducting is an important element within the modelling process. This paper reports on a new approach in analysing mass and energy transport through a pipe system using the mesh method.A new system has been developed for monitoring wave energy and gas properties, using a two-dimensional grid to represent the time-mesh boundary domain. This approach has allowed for refinement of the current mesh method by allowing more accurate monitoring of gas properties.The modified method was tested using measured results from a Single-Shot Rig. A CFD analysis was also conducted and compared with the new method. The new method performed very well on the range of pipe geometries tested.