Effects of engine operating and design variables on exhaust emissions

Journal Article · Sat Jan 01 04:00:00 EST 1972 · SAE Prog. Technol.; (United States)

OSTI ID:6647608

Hagen, D F; Holiday, G W

To determine the influence of engine variables on the composition of exhaust gas, engine dynamometer tests were conducted on single and multicylinder reciprocating engines. The following engine variables were investigated: air-fuel ratio, power output, engine speed, spark timing, exhaust back pressure, valve overlap, combustion chamber deposits, and intake manifold pressure. Hydrocarbon concentrations were found to be considerably affected by changes in air-fuel ratio, spark timing, intake manifold pressure, and combustion chamber deposits. Somewhat less change in hydrocarbon concentration was obtained by varying valve overlap and engine speed. Changes in engine power output and exhaust back pressure had little effect on hydrocarbon concentrations. Carbon monoxide concentrations were principally affected by changes in the air-fuel ratio. No other variables affected carbon monoxide concentration except where air-fuel ratio was indirectly influenced. The influence of changes in the variables on hydrocarbon and carbon monoxide emissions in pounds per hour was also determined. Vehicles were tested on the road and chassis dynamometer to investigate the effect of air-fuel ratio, spark timing, and valve overlap on hydrocarbon and carbon monoxide concentrations. Carburetion leaning, spark timing retardation, and reduction of valve overlap produced concentration reductions in line with those predicted from engine dynamometer studies.

• OSTI ID: 6647608
• Journal Information: SAE Prog. Technol.; (United States), Journal Name: SAE Prog. Technol.; (United States) Vol. 6; ISSN SAPTA
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330101 -- Internal Combustion Engines-- Spark-Ignition
330700* -- Advanced Propulsion Systems-- Emission Control
AIR POLLUTION CONTROL
AUTOMOBILES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL COMPOSITION
DATA
ENGINES
EXHAUST GASES
EXPERIMENTAL DATA
FLUIDS
FUEL-AIR RATIO
GASEOUS WASTES
GASES
HEAT ENGINES
HYDROCARBONS
INFORMATION
INTERNAL COMBUSTION ENGINES
NUMERICAL DATA
OPERATION
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
SPARK IGNITION ENGINES
VEHICLES
WASTES