Modeling and optimization of slow speed two stroke marine Diesel engine using Multi zone combustion model

Abstract

this paper presents the process calculation and modeling of a slow speed two stroke marine Diesel engine using AVL Boost software. Unlike the previous models based on Vibe’s calculation process, where the pressure and temperature are calculated only inside the engine cylinder, in the Boost software, and applied Multi zone combustion model the losses in the intake and exhaust system and other processes of changing the condition and composition of the gas are calculated in the whole engine. Software performs one-dimensional calculations, which means that 3D calculation models of an engine are not made, but the influence of three-dimensional geometry is taken into account by means of flow coefficient, which represent the ratio of an actual flow at some point and the theoretic isentropic flow without losses. The AVL Boost Multi-zone combustion model was applied to a slow speed two stroke marine Diesel engine. The calibration and validation of the model was carried out with the testbed results of the 75% load test of a real engine.