A transient SI engine model for vehicle dynamic simulation. Ph.D. Thesis

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1994

OSTI ID:237309

Huang, R W

This study details an investigation into the modeling and simulation of spark-ignition (SI) engines, engine components, and vehicle powertrain systems. The work expands on previous studies in three areas: the description of powertrain system and its components, the formulation of SI engine component models and overall engine model, and lastly, the sensitivity analysis of the engine model and the simulation of powertrain systems. A mathematical model of SI engines, with either carburator, single-port fuel injection, or multi-port fuel injection systems, is derived. In the present engine model, the engine internal torque is a function of air/fuel ratio, engine speed, and throttle plate position. This engine model can account for the sudden change in throttle plate angle and estimate the engine transient behavior. The powertrain subsystems are also described to a certain extent, and the integration of the present engine model and a specific powertrain system is verified by further computer simulation. The Taguchi method is applied in sensitivity analysis (constant engine speed) which allows for an understanding of the engine parameters that are necessary to include in the model. In addition, the control variables which affect the engine dynamics and states can be examined. Using the simulation results, a simple fuel enrichment strategy is derived in order to compensate air-fuel mixture lean/rich tendency when the throttle plate is opened/closed rapidly. This confirms the controllability of the present engine model. Furthermore, a flywheel is attached to the engine crankshaft to emulate a powertrain system and account for the change in engine speed. Finally, the present engine model and a specific powertrain system are integrated and simulated to demonstrate their application in full-vehicle simulation.

• Research Organization: California Univ., Davis, CA (United States)
• OSTI ID: 237309
• Report Number(s): N--96-22749; NIPS--96-08986
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
CARBURETORS
COMPUTERIZED SIMULATION
FUEL-AIR RATIO
MATHEMATICAL MODELS
MECHANICAL TRANSMISSIONS
SPARK IGNITION ENGINES
TORQUE