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In response to the emissions standards for diesel engines, it is essential to have separate aftertreatment devices for controlling the specific tailpipe emissions like HC, CO, NOx, and particulate matter. An advanced diesel exhaust aftertreatment system consists of channel-flow catalytic converters such as diesel oxidation catalyst (DOC), selective catalyst reduction (SCR) and wall-flow diesel particulate filters (DPF) each with discrete functions. Because of this multi-component aftertreatment system configuration, there are an increase in system complexity, development time and cost for doing experiments in order to evaluate various options and find the optimum aftertreatment system architecture. The objective of this work is the development and application of an integrated aftertreatment system model including DOC, SCR, DPF and all connecting pipes. The study includes the baseline system performance, i.e.

As emissions regulations are becoming increasingly stringent worldwide, multiple exhaust aftertreatment devices are considered in order to minimize diesel engine tailpipe emissions. This paper presents the development of an integrated model of an advanced diesel aftertreatment system that consists of a diesel oxidation catalyst (DOC), a Lean NOx Trap (LNT), a diesel particulate filter (DPF), and connecting exhaust pipes. All component models are incorporated into a unified diesel exhaust aftertreatment simulation tool with uniform I/O in MATLAB/Simulink. The platform and approach to incorporate all component models into a single system model are described. The developed integrated diesel aftertreatment system model has been employed to simulate tailpipe emissions of a light-duty vehicle over the US Federal Test Procedure (FTP) emission certification cycle.

This study employs experimental and computational methods to investigate the thermal state of the exhaust manifold of a multi-cylinder turbocharged diesel engine operating under steady-state conditions. The local skin temperatures and surface heat fluxes varied significantly throughout the external surface of the manifold. The augmentation of the local heat flux with increasing load and engine speed may be represented solely by the increase in the fuel mass flow rate. The results of the 1D simulation are in good agreement with the measurements of the exit gas temperatures, skin temperatures, and surface heat fluxes.

A one-dimensional engine model was developed for a 4.9-liter V-configuration 6-cylinder turbocharged direction-injection diesel engine. The engine model was first calibrated using the experimental data taken on dynamometer at eight steady-state engine operating conditions. Then the model was extensively validated with four transient dynamometer tests that were conducted mainly with step changes in the engine load, the EGR valve position, the intake throttle position, and/or the VGT vane position. It is shown that the developed model predicts the engine performance and gas dynamics with an error less than 3% in general, both at steady-state and transient engine operating conditions. The validated engine model is very useful in several future applications, such as engine development and optimization, and engine and aftertreatment system integration.