Validation of a Non-Isentropic, Pressure Loss, Branched Pipe Junction Model
Previous papers from The Queen's University of Belfast have described a new non-isentropic branched pipe junction model for use in a one-dimensional gas dynamic simulation of a multi-pipe system subject to unsteady gas flow. Such assemblages are commonly found in the intake and exhaust systems of multi-cylinder engines. The model takes full account of the effect of pressure loss, due to change in flow direction, and tracks the properties and composition of gas mixtures through the junction. Although the validity of the model has previously been inferred by its use in a complete engine simulation, which accurately predicted parameter variation in a firing engine, the independent validation of the junction model by itself is only now demonstrated. To investigate the performance of the junction model a series of three-pipe junctions were tested by directing a single pressure wave through each of the previously quiescent junctions.