Temperature Effects on Emissions of an Active Thermally Controlled Spark Ignition Single-Cylinder Engine

The primary goal of this research was to advance the single-cylinder engine transient test system. This system is comprised of several subsystem that address the physical dynamics of a multi-cylinder engine in the effort to replicate them on a single-cylinder engine. The subsystems are a thermally controlled water jacket, transient hydrostatic dynamometer system, engine management system and intake air simulator used to replicate multi-cylinder rotational dynamics and intake gas dynamics. The central focus of this effort is to provide an initial evaluation of the heat transfer system that is intended to replicate the cylinder to cylinder heat transfer dynamics in a multi-cylinder engine. The heat transfer in each of the seven zones circumferentially around the liner are individually controlled to replicate the variation in temperature and subsequent heat transfer, thereby replicating the thermal dynamics of one cylinder in the multi-cylinder engine as a whole. The evaluation provided insight to design improvements to the hardware and control. As part of this study nitrogen oxide exhaust emissions were measured. The heat transfer system was evaluated in its ability to influence these emission through direct control of the cylinder wall temperatures. The outcome of this research can be used to advance the single-cylinder engine transient test system. This will thereby cultivate the overarching goal to minimize the overall development time of production engines by making it possible to conduct a wider range of tests on single-cylinder engines with a high confidence that results accurately reflect those of multi-cylinder engine testing.