Multi-Objective Optimization of Fuel Consumption and NOx Emissions using a Stochastic Reactor Model, THIESEL 2018 Conference on Thermo-and Fluid Dynamic Processes in Direct …

The 0D DI-SRM with tabulated chemistry is successfully applied for a multi-objective optimization of fuel consumption and NO x emissions in a direct injection Diesel engine. The approach highlighted its strength to account for physical and chemical effects in a 0D model framework with a lesser extent of computational costs. The optimization results show that increasing compression ratio has the highest potential for reducing fuel consumption especially at part load conditions. Increasing the EGR rate is most effective in reducing the NO x emissions of all operating points. The average optimization time is 30h on three cores of an Intel i7-7820HQ CPU. Multi-Objective Optimization with 0D DI-SRM The specific fuel consumption (ISFC) and NO x emissions (sNO x) shall be minimized for each operating point by tuning the parameters in Table 2. The constraints are 200bar peak cylinder pressure (PCP) and 1000K turbine inlet temperature (TIT). The optimization results are shown in Figure 3 and Figure 4. The relative change of the given property compared to the base case is depicted in percent. The compression ratio is found to be most effective for improving fuel consumption. Especially part load operating points show the highest potential regarding increased compression ratio. The EGR rate is the most effective parameter to reduce the NO x emissions for all operating points. Full load operating points show only a minor potential for improving ISFC and sNO x since they are limited by PCP and TIT. [1] Matrisciano A., Franken T., Perlman C., Borg A.