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Time-averaged combustion chamber surface temperatures and surface heat fluxes were measured at three locations (one in the antechamber and two in the main chamber) on the head of a single-cylinder, divided-chamber diesel engine. In general the surface temperature and heat flux were found to increase with increasing engine speed, fuel-air ratio and intake-air temperature, decreasing coolant temperature and advancing combustion timing. At motored conditions the highest heat flux was at the antechamber location. This was caused by the high swirl flows present in the antechamber. In contrast, at all other conditions the highest heat flux was measured at the location in the main chamber near the valves. This was attributed to the convective action of the high-temperature stream of combustion gases exiting the antechamber during the expansion stroke. Lastly, the local surface heat flux measurements were correlated in terms of the air and fuel consumption rates of the engine.

In this study, the effects of engine speed, air-fuel ratio, combustion timing, intake-air temperature, and coolant and oil temperature on exhaust gaseous emissions (nitric oxide, carbon monoxide and hydrocarbons) and particulate emissions (particulates, volatiles and smoke) were investigated in a single-cylinder, divided-chamber diesel engine. In addition, the trade-off behavior of the pollutants was investigated. To aid in the interpretation of the experimental findings, a single-chamber, single-zone heat release model utilizing experimental main-chamber pressure-time data was employed. The large increase in nitric oxide emission index caused either by increasing the air-fuel ratio or by advancing the combustion timing is attributed to the proportionally larger amounts of fuel that burn at near TDC conditions.