The combustion chambers of a V8 Otto cycle engine with a 7.8:1 compression ratio, bore of 3.98 inches, and 410-cubic-inch displacement can be approximated as right circular cylinders. The engine operates at 3000 RPM using gasoline at an AF 15.2 and a volumetric efficiency of 95%. When combustion occurs, the flame is dampened out near the walls and a boundary layer of air-fuel does not get burned. Combustion is at constant volume at TDC, and the unburned boundary layer can be considered to be 0.004 inch thick over the entire combustion chamber surface. Fuel is originally distributed equally throughout the chamber. Calculate: (a) Percent of fuel that does not get burned due to being trapped in the surface boundary layer. [90] (b) Amount of fuel lost in the exhaust due to this boundary layer. [lbm/hr] (c) Chemical power of the fuel lost in the exhaust. [hp]
Attachments:
image_4670347610091498117.jpg
