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.
Citation: Schernus, C., van der Staay, F., Janssen, H., Neumeister, J. et al., "Modeling of Exhaust Valve Opening in a Camless Engine," SAE Technical Paper 2002-01-0376, 2002, https://doi.org/10.4271/2002-01-0376. Download Citation
Author(s):
C. Schernus, F. van der Staay, H. Janssen, J. Neumeister, B. Vogt, L. Donce, I. Estlimbaum, E. Nicole, C. Maerky
Affiliated:
FEV Motorentechnik GmbH, Johnson Controls Automotive Electronics SA
Pages: 15
Event:
SAE 2002 World Congress & Exhibition
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
Design of Racing and High-Performance Engines 1998-2003-PT-100, Modeling of SI Engines and Multi-Dimensional Engine Modeling-SP-1702, SAE 2002 Transactions Journal of Engines-V111-3
Related Topics:
Variable valve timing
Exhaust valves
Valve trains
Computer simulation
Fuel economy
Valves
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