Application of multicriteria decision making methods to compression ignition engine efficiency and gaseous, particulate, and greenhouse gas emissions.
Compression ignition (CI) engine design is subject to many constraints, which present a multicriteria optimization problem that the engine researcher must solve. In particular, the modern CI engine must not only be efficient but must also deliver low gaseous, particulate, and life cycle greenhouse gas emissions so that its impact on urban air quality, human health, and global warming is minimized. Consequently, this study undertakes a multicriteria analysis, which seeks to identify alternative fuels, injection technologies, and combustion strategies that could potentially satisfy these CI engine design constraints. Three data sets are analyzed with the Preference Ranking Organization Method for Enrichment Evaluations and Geometrical Analysis for Interactive Aid (PROMETHEE-GAIA) algorithm to explore the impact of (1) an ethanol fumigation system, (2) alternative fuels (20% biodiesel and synthetic diesel) and alternative injection technologies (mechanical direct injection and common rail injection), and (3) various biodiesel fuels made from 3 feedstocks (i.e., soy, tallow, and canola) tested at several blend percentages (20-100%) on the resulting emissions and efficiency profile of the various test engines. The results show that moderate ethanol substitutions (~20% by energy) at moderate load, high percentage soy blends (60-100%), and alternative fuels (biodiesel and synthetic diesel) provide an efficiency and emissions profile that yields the most "preferred" solutions to this multicriteria engine design problem. Further research is, however, required to reduce reactive oxygen species (ROS) emissions with alternative fuels and to deliver technologies that do not significantly reduce the median diameter of particle emissions.
International Laboratory for Air Quality and Health, Queensland University of Technology, 2 George Street, Brisbane QLD 4001, Australia.
Nicholas C
NC
Surawski
Branka
B
Miljevic
Timothy A
TA
Bodisco
Richard J
RJ
Brown
Zoran D
ZD
Ristovski
Godwin A
GA
Ayoko
D000465:Algorithms; D056804:Biofuels; D003661:Decision Support Techniques; D004867:Equipment Design; D000431:Ethanol; D005740:Gases / Q000032:analysis*; D017752:Greenhouse Effect; D052638:Particulate Matter / Q000032:analysis*; D001335:Vehicle Emissions
D056804:Biofuels; D005740:Gases; D052638:Particulate Matter; D001335:Vehicle Emissions; D000431:Ethanol