Numerical Simulation to Assess Implementation of Variable Valve Timing and Lift Technique on a BSVI LMD Diesel Engine for FE Improvement

A previous study using a cycle simulation program had identified the possibility that highly rated diesel engines might benefit from a variable valve timing (VVT) system. In particular, the study had shown that, by delaying the start of inlet valve opening at part load, it should be possible to eliminate the reverse flow that can lead to inlet port fouling. The work reported here encompasses the design and implementation of a variable valve timing system on a highly rated high-speed marine diesel engine. The principal topics addressed are the selection and design of a mechanism, a comparison between the predictions and results from mechanism testing on a single-cylinder valve-train rig and the engine performance predictions and results obtained when the mechanism was tested on the engine. The results from the single-cylinder test rig demonstrated that the mechanism performed satisfactorily, and this led to a design suitable for retro-fitting to the engine. The engine was comprehensively instrumented and the experimental results were in good agreement with the cycle simulation predictions.

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Numerical Calibration of Diesel Engine Variable Valve Timing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.516-517.628 ◽

2012 ◽

Vol 516-517 ◽

pp. 628-633

Author(s):

Sheng Ou Hu ◽

Ren Xian Li

Keyword(s):

Diesel Engine ◽

Working Conditions ◽

Combustion Engine ◽

Engine Performance ◽

Simulation Method ◽

Calibration Method ◽

Operating Conditions ◽

Variable Valve Timing ◽

Valve Timing ◽

Variable Valve

The performance of internal combustion engine can be improved by using variable valve timing technology. but how to get the optimal inlet/export valve open or close angles under various operating conditions still relies mainly on testing calibration method. By means of one-dimensional working process simulation method, the performance of a four cylinder diesel engine was simulated, and the influences of diffrent inlet/export valve timing on engine performances were compared. Optimum valve timing values and engine performances under thirty kinds of working conditions were gotton. After that, the engine performances compared with that without variable valve timing. Simulation results show that the engine performance, especially the emission performance, can be improved at all simulation working conditions. The method used in this paper may be a new way for calibration of optimal valve timing.

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Simulation and Analysis of Variable Valve System Based on Diesel Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.1271 ◽

2014 ◽

Vol 556-562 ◽

pp. 1271-1277 ◽

Cited By ~ 1

Author(s):

Long Yin ◽

Dong Jian Zeng ◽

Yi Zeng Peng

Keyword(s):

Diesel Engine ◽

Simulation Model ◽

Engine Speed ◽

Drive System ◽

Variable Valve Timing ◽

Valve Timing ◽

Experiment Data ◽

Valve System ◽

Valve Drive ◽

Variable Valve

The necessity and superiority of using variable valve system on diesel is described detailed. The design of electro-hydraulic variable valve drive system is introduced based on DK4A diesel engine, then the mathematical simulation model of the electro-hydraulic variable valve drive system is undertook by Simulink in order to study the movement of the intake valve. The results show the design of variable valve system can achieve the variable valve timing continuous vary in different engine speed and respond quickly. Further, the simulation model of the diesel engine is built by GT-POWER, and then the accuracy of the model is verified according to the experiment data. Lastly the intake performance of the variable valve system in different out flowing phase is analyzed through the GT-POWER model. The results show that when the engine speed at 2000RPM, 2800RPM, 3600RPM, out flowing phase behind 60oCA, 45oCA, 35oCA after intake TDC respectively ,the amount of intake air decreases with the increase of the out flowing phase, the amount of intake air has been effectively controlled by variable valve system.

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