One dimensional compression ignition engine simulation and comparison of soot emission models

Abstract

In this thesis 2.2 liter compression-ignition (CI) engine having 4-cylinders with a turbocharger is modeled through AVL BOOST under both full-load and 80%, 60%, and 40% partial loads. The study carried out can be classified into three distinct phases including base model correlation, full-load correlation, and comparison of phenomenological soot models with measured data. Firstly, the base model calibration is made to match the experimental peak firing pressure results, and determine the combustion parameters such as start of combustion (SOC), combustion duration (CD), and shape (m) & vibe (a) parameters correctly without taking the turbocharger path into account. In that context, the engine model is constructed by placing the required elements into BOOST workspace, and then the required geometrical & thermodynamic data are introduced. After determining these parameters which is mentioned above, full-load correlation of the selected engine is made. In the study, with the aim of predicting the soot particles more precisely, Vibe 2-Zone combustion model is selected since it provides more accurate results with phenomenological soot models such as Hiroyasu, and Schubiger. In the full-load correlation phase, the performance of the engine is evaluated by comparing the calculated performance based parameters including brake-mean effective pressure (BMEP), break-specific fuel consumption (BSFC), torque, air-fuel ratio (AFR), power, friction mean effective pressure (FMEP), indicated mean effective pressure (IMEP) with measured data at all 35-speed modes ranging from 1000 to 4400 rpm. Finally, the soot correlation of the engine is made relying on phenomenological Schubiger, and Hiroyasu soot models.