PRECOMBUSTION CHAMBER PERFORMANCE AND EMISSIONS STUDIES ON A LARGE-BORE SINGLE CYLINDER NATURAL GAS ENGINE
Abstract
Natural gas accounts for 32 percent of the United States’ total energy consumption [1], and as emissions regulations become more stringent, the need to reduce harmful emissions produced by natural gas engines has become increasingly important. One solution is to burn air-fuel mixtures in open chamber spark ignition with very lean air-fuel ratios, which reduces oxides of nitrogen (NOx) emissions. However, this process dramatically increases carbon monoxide (CO) and hydrocarbon (HC) emissions. To combat harmful emission, a precombustion chamber (PCC) can be introduced into the system. A PCC is a small chamber, about 1 to 2 percent of the main chamber’s clearance volume, that ignites a near stoichiometric air-fuel mixture and ejects an explosive jet into the main chamber. As a result, approximately one million times greater ignition energy is released compared to a normal spark plug [2] [3] [4]. Combustion stabilizes and in-cylinder temperatures are reduced, which reduces CO, HC, and NOx emissions.
This thesis provides performance and emissions data on three PCCs supplied by Cooper Machinery Services on an Ajax E-565 natural gas engine. A spark-ignited precombustion chamber for engine bore sizes of 10.5 inches up to 13.25 inches was tested to obtain performance and emissions data. Two other PCCs, Eco-Jets, were tested for the first time on an Ajax E-565 engine to obtain performance and emissions data. The novel results were analyzed, and further research and design opportunities were provided with a goal to reduce overall emissions, improve combustion stability, and improve engine performance.
Subject
prechamberPCC
natural gas
emissions
efficiency
engine
performance
clean energy
NOx
nitric oxide
CO2
carbon dioxide
THC
total hydrocarbons
CO
carbon monoxide
precombustion chamber
Citation
Ward, Kyle Blair (2021). PRECOMBUSTION CHAMBER PERFORMANCE AND EMISSIONS STUDIES ON A LARGE-BORE SINGLE CYLINDER NATURAL GAS ENGINE. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /193248.