Browse Publications Technical Papers 2002-01-0376
2002-03-04

Modeling of Exhaust Valve Opening in a Camless Engine 2002-01-0376

Electromechanical valve trains in camless engines enable virtually fully variable valve timing that offers large potential for both part load fuel economy and high low end torque. Based upon the principle of a spring-mass-oscillator, the actuator stores the energy to open and close the valves in springs. However, the motion of the valves and the electromechanical actuation suffers from parasitic losses, such as friction and ohmic resistance. Besides eddy current losses, gas forces obviously play a further important role in the control of exhaust valve opening especially at high engine speeds and loads. Based on engine test bench data, computational simulations (3D CFD, gas exchange process and electromechanical system) are carried out to analyze the effects of exhaust valve gas forces on the dynamic motion of valve and actuator. The modeling approach and results of this investigation are discussed in this paper.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.

Due to current capacity constraints, printed versions of our publications - including standards, technical papers, EDGE Reports, scholarly journal articles, books, and paint chips - may experience shipping delays of up to four to six weeks. We apologize for any inconvenience.
We also recommend:
TECHNICAL PAPER

Variable Valve Timing By Means of a Hydraulic Actuation

2000-01-1220

View Details

TECHNICAL PAPER

Advantage of Lightweight Valve Train Component on Engines

980573

View Details

TECHNICAL PAPER

A Rotary Valve Controlled High Expansion Ratio Gasoline Engine

940815

View Details

X