Designing optimal control maps for diesel engines for high efficiency and emission reduction

Abstract

The objective of this paper is to design static optimal control maps of diesel engines to achieve high efficiency and emission reduction. The calibration tool applied to create the control maps, named "Off-line parameterization tool", was designed based on the Design of Experiments method. The optimization goal is to minimize the Brake Specific Fuel Consumption (BSFC) by the engine's input parameters under emission constraints. The tool was designed to work both fully automatically and semi-automatically. Many reports on engine calibration have taken the Design of Experiments (DoE) approach, but their implementations in choosing experimental design types and optimization processes are different compared to this paper. The unique aspect of this research lies in the significant properties of the Off-line parameterization tool. First, this tool is flexible: it is able to work with multiple inputs and multiple outputs. Second, it can reduce the calibration time as the engine running time is kept as short as possible and all the data processing work is accomplished automatically.

Operational Profile Based Optimization Method for Maritime Diesel Engines

“…According to the proposed method in [13], by running the Design of Experiments (DoE) method [19] on selected operating points (speed-load), the BSFC and the NO x emissions at each point are presented as the functions of fuel injection timing (SoI), common rail pressure (FIP) and charged air pressure (P charge ). The two functions are expressed in Equations ( 3) and (4).…”

“…This nonlinear constrained minimization problem is solved by using the Sequential Quadratic Programming method [20]. However, the constraint limit α has not been efficiently investigated in [13] as the IMO emission regulations have not been considered. Therefore, the following algorithm introduces a method to fully investigate all possibilities of α in order to achieve the optimal result.…”

“…According to the method in [13], the DoE test plan is made based on the operating range of the engine shown in Table 4, where the selected 14 test points are marked by " ". Every operating point is tested for 13 runs according to the Box-Behnken design method described in [13]. The levels of the parameters SoI, P charge and FIP are decided based on the engine's nominal values.…”

“…This research presents an operational profile based diesel engine optimization method, specifically targeting to large bore, medium-speed diesel engines used in marine transportation and in stationary power plants. The fundamental optimization algorithm is inherited from the proposed method in [13] and then extended in this work with the presence of engine's operational profiles. The IMO emission regulation for Nitrogen Oxide (NO x ) is taken as nonlinear constraint for the optimization.…”