Optimization of diesel fuel injection strategies through applications of cooperative particle swarm optimization and artificial bee colony algorithms

New engine hardware and injection strategies allow modern engines to meet stringent emissions regulations but can require extensive engine testing to identify optimum operating points. Swarm intelligence algorithms, which do not require knowledge of the search space gradient, can provide a short cut in finding optimum operating parameters in reduced experimental time than a traditional design of experiments study. In this paper, a modified artificial bee colony (ABC) algorithm and a cooperative particle swarm optimization (CPSO) algorithm are applied to triple and quadruple injection routines. The optimization was applied directly to the operation of a four-cylinder turbocharged production diesel engine operating at a high exhaust gas recirculation rate and medium load. Six and eight variable optimizations were carried out for triple and quadruple injection schedules, respectively. In experimental testing, the cooperative particle swarm optimizer significantly reduced soot and carbon monoxide emissions in only 84 engine tests when using a pilot-pilot-main-post schedule. The modified artificial bee colony algorithm took 176 engine tests to optimize a pilot-main-post triple-injection schedule and was not applied to the four-injection routine.