Effects of Ambient Conditions on the Emissions of a Small Carbureted Four-Stroke Engine 961739
The exhaust-gas emissions of a small four-stroke, carbureted, single-cylinder spark-ignition engine have been studied as functions of ambient conditions, using gasoline as the fuel. In steady-state dynamometer tests at fixed engine speeds/loads, carried out under different climatic conditions, the concentrations of exhaust-gas components have been measured. Their dependence on ambient conditions has been analyzed principally in terms of the influence of ambient temperature, pressure, and humidity on the air-fuel ratio metered by the carburetor. While the air-fuel ratio of carbureted utility engines at fixed loads varies by only a small percentage during modest changes in ambient air conditions, these changes can correspond to significant changes in the production of regulated pollutants. Using a correction for air mass flow and fuel density at wide open throttle, the scatter in observed air-fuel ratio and % CO data could be reduced by about one third.
Citation: Brereton, G., DeAraujo, A., and Bertrand, E., "Effects of Ambient Conditions on the Emissions of a Small Carbureted Four-Stroke Engine," SAE Technical Paper 961739, 1996, https://doi.org/10.4271/961739. Download Citation
Author(s):
G. J. Brereton, A. DeAraujo, E. Bertrand
Affiliated:
Michigan State Univ.
Pages: 12
Event:
International Off-Highway & Powerplant Congress & Exposition
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
Design, Modeling, and Emission Control for Small Two- and Four-Stroke Engines-SP-1195, SAE 1996 Transactions - Journal of Engines-V105-3
Related Topics:
Air / fuel ratio
Spark ignition engines
Emissions
Throttles
Gasoline
Humidity
Pressure
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