Mixture Preparation in a SI Engine with Port Fuel Injection During Starting and Warm-Up
922170
10/01/1992
- Event
- Content
- The in-cylinder hydrocarbon (HC) mole fraction was measured on a cycle-resolved basis during simulated starting and warm-up of a port-injected single-cylinder SI research engine on a dynamometer. The measurements were made with a fast-response flame ionization detector with a heated sample line. The primary parameters that influence how rapidly a combustible mixture builds up in the cylinder are the inlet pressure and the amount of fuel injected; engine speed and fuel injection schedule have smaller effects. When a significant amount of liquid fuel is present at the intake port in the starting process, the first substantial firing cycle is often preceded by a cycle with abnormally high in-cylinder HC and low compression pressure. An energy balance analysis suggests that a large amount of liquid vaporization occurs within the cylinder in this cycle. Additionally, it was found that prevaporizing the fuel using a specially designed heated injector is effective for rapid starting and reduction of overfueling requirements during warm up.
- Pages
- 14
- Citation
- Fox, J., Min, K., Cheng, W., and Heywood, J., "Mixture Preparation in a SI Engine with Port Fuel Injection During Starting and Warm-Up," SAE Technical Paper 922170, 1992, https://doi.org/10.4271/922170.