1D model of pulsating flows in pipes dynamics using MOC.

Abstract

This paper presents a model of 1D pulsating flows in partially opened pipes. This is typical of inlet and exhaust pipes of internal combustion engines and piston compressors. The introduction describes the current state of affairs at one dimensional modeling pulsations according to the Method of Characteristics (MOC). Subsequently, the main idea of MOC is presented. In the fourth chapter general guidelines at initial and boundary conditions were presented. The parameters were analyzed at space times domain as 3D diagrams. Next, two crucial resonant frequencies are presented: first and second waveform which can be defined as a quarter and half-length waves. Firstly, partially open end phenomena at space and stage plane were presented. Secondly, the theory of acoustic wave propagation with description of stage waves at analyzed ends of pipe was shown. Finally, existing test rig dedicated to research the pulsating flow in pipes was shortly presented. This test rig was built at Flow Metrology Division of Lodz University of Technology. In the second part of this chapter the main assumption of an elaborated simulation algorithm at Matlab Simulink environment was shown. Lastly, simulation results compared with presented conceptions of modeling those systems with the emphasis into pulsation dynamics according to resonant frequencies were discussed.