Numerical simulation of a two-dimensional flow field in a motored engine with a prechamber using a k-.EPSILON. turbulence model.

Abstract

To understand flow behavior during the compression and expansion strokes in a reciprocating engine with a horizontal prechamber, spatial and temporal distributions of flow velocity, turbulence intensity, turbulence kinetic energy and its dissipation rate in both the pre- and main chambers are calculated numerically using a two-dimensional flow model and k-e turbulence model. As a consequence, the velocity vectors, the contour maps of turbulence kinetic energy and its dissipation rate are found to be influenced considerably by the torch jet flow or torch nozzle size. Further, the spatial and temporal distributions of velocity and turbulence in the main chamber are in reasonable agreement with the ones measured using a LDA, only within small crank angle range near the top dead center (TDC) able to be maintained two-dimensionality in the flow field.