Study on Modeling of Electro-Hydraulic Variable Valve Mechanism Based on CATIA

2010 ◽  
Author(s):  
Yanhua Gu ◽  
Hua Li ◽  
Fafa Liu ◽  
Yunkai Wang ◽  
Yingnan Guo
Keyword(s):  
Valve Mechanism ◽  
Variable Valve

Effects of variable valve timing on the air flow parameters in an electromechanical valve mechanism – A cfd study

Fuel ◽  
2022 ◽  
Vol 308 ◽  
pp. 121956
Author(s):  
Usame Demir ◽  
Gokhan Coskun ◽  
Hakan S. Soyhan ◽  
Ali Turkcan ◽  
Ertan Alptekin ◽  
...  
Keyword(s):  
Air Flow ◽  
Variable Valve Timing ◽  
Valve Timing ◽  
Valve Mechanism ◽  
Flow Parameters ◽  
Variable Valve

Variable Valve Actuation Mechanism Using Magnetorheological Fluid

2005 ◽  
Author(s):  
H. Hirani ◽  
S. Dani
Keyword(s):  
Valve Lift ◽  
Frictional Torque ◽  
Valve Mechanism ◽  
Actuation Mechanism ◽  
Variable Valve Actuation ◽  
Lift Mechanism ◽  
Variable Valve Lift ◽  
Direct Acting ◽  
Variable Valve ◽  
And Control

A magnetorheological (MR) fluid based variable valve lift mechanism is presented. A test setup is designed to measure the frictional-torque and valve-displacement of a direct acting valve mechanism under various speed conditions. Results of valve lifts at different speeds and control currents are presented.

Study on the influences of oil supply pressure and maximum opening of electromagnetic valve on upstream pressure fluctuation

2019 ◽  
pp. 146808741987285
Author(s):  
Zhiqiang Han ◽  
Mingyan Hu ◽  
Jiahui Zhao ◽  
Wenbin Yu
Keyword(s):  
Characteristic Parameter ◽  
Pressure Variation ◽  
Hydraulic Circuit ◽  
Valve Mechanism ◽  
Electromagnetic Valve ◽  
Oil Supply ◽  
Supply Pressure ◽  
Instantaneous Pressure ◽  
Variable Valve ◽  
Maximum Opening

The pressure fluctuation in the hydraulic pipeline in the electro-hydraulic variable valve mechanism will cause the instability of the oil pressure in the hydraulic chamber, thereby making the valve movement characteristics unpredictable, which can affect the adjustment function of the valve mechanism to the air intake, and further affect the combustion, emission, and fuel consumption of the engine. In this article, a simulation model is established for the working process of a certain type of marine diesel engine’s electro-hydraulic variable valve system, and the simulation and experiment are combined to study the influence of the hydraulic oil supply pressure P0 (10–13 MPa) and the maximum opening d (2.5–4 mm) of the electromagnetic valve on the upstream instantaneous pressure variation of the hydraulic circuit of the electromagnetic valve. The fluctuation curve of instantaneous pressure variation is divided into three stages (I a–b, II b–c–d, and III d–e), and the characteristic values ( Pa, Pb, Pc, Pd, Pe) and characteristic phases ( βa, βb, βc, βd, βe) at the inflection point of the fluctuation curve are selected to describe the influence of the hydraulic oil supply pressure and the maximum opening of the inlet electromagnetic valve on the upstream instantaneous pressure variation of the hydraulic circuit of the electromagnetic valve. The result shows that the decrease in the characteristic parameters Pa and Pc values and the increase in the Pb and Pd values increase with the increase in the oil supply pressure and the maximum opening. When the maximum opening is constant, the decrease in the characteristic parameter Pe value increases with the increase in the oil supply pressure; when the oil supply pressure remains unchanged, the difference in the characteristic parameter Pe value is less than 0.04 MPa at different maximum openings, which is hardly affected by the maximum opening; and the influence of the oil supply pressure and the maximum opening on the characteristic phase βa-e is very different.

Recent Patents on Valve Mechanism Device

2020 ◽  
Vol 13 (3) ◽  
pp. 230-241
Author(s):  
Ye Dai ◽  
Hui-Bing Zhang ◽  
Yun-Shan Qi
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Flow Direction ◽  
Research Progress ◽  
Valve Mechanism ◽  
Advantages And Disadvantages ◽  
Valve Structure ◽  
Valve Leakage ◽  
Safety And Reliability

Background: Valves are an important part of nuclear power plants and are the control equipment used in nuclear power plants. It can change the cross-section of the passage and the flow direction of the medium and has the functions of diversion, cutoff, overflow, and the like. Due to the earthquake, the valve leaks, which will cause a major nuclear accident, endangering people's lives and safety. Objective: The purpose of this study is to synthesize the existing valve devices, summarize and analyze the advantages and disadvantages of various devices from many literatures and patents, and solve some problems of existing valves. Methods: This article summarizes various patents of nuclear-grade valve devices and recent research progress. From the valve structure device, transmission device, a detection device, and finally to the valve test, the advantages and disadvantages of the valve are comprehensively analyzed. Results: By summarizing the characteristics of a large number of valve devices, and analyzing some problems existing in the valves, the outlook for the research and design of nuclear power valves was made, and the planning of the national nuclear power strategic goals and energy security were planned. Conclusion: Valve damage can cause serious safety accidents. The most common is valve leakage. Therefore, the safety and reliability of valves must be taken seriously. By improving the transmission of the valve, the problems of complicated valve structure and high cost are solved.

Cylinder Deactivation with Mechanically Fully Variable Valve Train

2012 ◽  
Vol 5 (2) ◽  
pp. 207-215 ◽  
Author(s):  
Rudolf Flierl ◽  
Frederic Lauer ◽  
Michael Breuer ◽  
Wilhelm Hannibal
Keyword(s):  
Valve Train ◽  
Cylinder Deactivation ◽  
Variable Valve Train ◽  
Variable Valve

Variable Valve Train Concept for Compliance with Future Diesel Emission Standards

MTZ worldwide ◽  
2021 ◽  
Vol 82 (2) ◽  
pp. 36-41
Author(s):  
Michael Elicker ◽  
Wolfgang Christgen ◽  
Jahaazeb Kiyanni ◽  
Maximilian Brauer
Keyword(s):  
Valve Train ◽  
Emission Standards ◽  
Variable Valve Train ◽  
Diesel Emission ◽  
Variable Valve

A Multi-Cylinder HCCI Engine Model for Control

2004 ◽  
Author(s):  
Jason S. Souder ◽  
Parag Mehresh ◽  
J. Karl Hedrick ◽  
Robert W. Dibble
Keyword(s):  
Design Process ◽  
Control Design ◽  
The Other ◽  
Variable Valve Timing ◽  
Valve Timing ◽  
Coupling Effects ◽  
Hcci Engine ◽  
Engine Model ◽  
Hcci Engines ◽  
Variable Valve

Homogeneous charge compression ignition (HCCI) engines are a promising engine technology due to their low emissions and high efficiencies. Controlling the combustion timing is one of the significant challenges to practical HCCI engine implementations. In a spark-ignited engine, the combustion timing is controlled by the spark timing. In a Diesel engine, the timing of the direct fuel injection controls the combustion timing. HCCI engines lack such direct in-cylinder mechanisms. Many actuation methods for affecting the combustion timing have been proposed. These include intake air heating, variable valve timing, variable compression ratios, and exhaust throttling. On a multi-cylinder engine, the combustion timing may have to be adjusted on each cylinder independently. However, the cylinders are coupled through the intake and exhaust manifolds. For some of the proposed actuation methods, affecting the combustion timing on one cylinder influences the combustion timing of the other cylinders. In order to implement one of these actuation methods on a multi-cylinder engine, the engine controller must account for the cylinder-to-cylinder coupling effects. A multi-cylinder HCCI engine model for use in the control design process is presented. The model is comprehensive enough to capture the cylinder-to-cylinder coupling effects, yet simple enough for the rapid simulations required by the control design process. Although the model could be used for controller synthesis, the model is most useful as a starting point for generating a reduced-order model, or as a plant model for evaluating potential controllers. Specifically, the model includes the dynamics for affecting the combustion timing through exhaust throttling. The model is readily applicable to many of the other actuation methods, such as variable valve timing. Experimental results validating the model are also presented.

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