scholarly journals Analysis of a high speed driven valve system of internal combustion engines with consideration of the design of valve-springs. 1st Report. Dynamic rehavior of a driven valve train.

1987 ◽  
Vol 53 (495) ◽  
pp. 2283-2288
Author(s):  
Kosuke NAGAYA
Keyword(s):  
High Speed ◽  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Valve Train ◽  
Combustion Engines ◽  
Valve System

Nonlinear Transient Response of a High Speed Driven Valve System and Stresses in Valve Springs for Internal Combustion Engines

1989 ◽  
Vol 111 (3) ◽  
pp. 264-271 ◽  
Author(s):  
K. Nagaya
Keyword(s):  
High Speed ◽  
Internal Combustion Engines ◽  
Three Dimensional ◽  
Beam Theory ◽  
Internal Combustion ◽  
Valve Train ◽  
Combination Method ◽  
Combustion Engines ◽  
Valve System ◽  
Cam Profile

This paper presents a method for solving the dynamic response problems of a driven valve system and the stress problem of valve springs for internal combustion engines. In this system there is hysteresis behavior in the spring constants during the rotation of the cam shaft. To treat this nonlinearity, the rigidity of each section is assumed to be one of a partly linear spring. For the valve trains, the cam profile is complex in general. To treat a general cam profile, this paper applies a combination method of the Fourier expansion, the Laplace transform and the analytical connection methods, and gives a response of valve trains. This paper also presents a theoretical result for the stresses in the valve spring due to the motion of the valve train based on the three dimensional curved beam theory.

Improving the tribological behavior of internal combustion engines via the addition of nanoparticles to engine oils

2015 ◽  
Vol 4 (4) ◽  
Author(s):  
Mohamed Kamal Ahmed Ali ◽  
Hou Xianjun
Keyword(s):  
Internal Combustion Engines ◽  
Tribological Behavior ◽  
Internal Combustion ◽  
Valve Train ◽  
Combustion Engines ◽  
Power Losses ◽  
Oil Consumption ◽  
Engine Oils ◽  
Engine Efficiency ◽  
Sliding Surfaces

AbstractThe friction between two sliding surfaces is probably one of the oldest problems in mechanics. Frictional losses in any I.C. engine vary between 17% and 19% of the total indicated horse power. The performance of internal combustion engines in terms of frictional power loss, fuel consumption, oil consumption, and harmful exhaust emissions is closely related to the friction force and wear between moving parts of the engine such as piston assembly, valve train, and bearings. To solve this problem, most modern research in the area of Nanotribology (Nanolubricants) aims to improve surface properties, reduce frictional power losses, increase engine efficiency, and reduce consumed fuel and cost of maintenance. Nanolubricants contain different nanoparticles such as Cu, CuO, TiO

scholarly journals A zonal approach for estimating pressure ratio at compressor extreme off-design conditions

2018 ◽  
Vol 20 (4) ◽  
pp. 393-404 ◽  
Author(s):  
José Galindo ◽  
Roberto Navarro ◽  
Luis Miguel García-Cuevas ◽  
Daniel Tarí ◽  
Hadi Tartoussi ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
High Speed ◽  
Internal Combustion Engines ◽  
Pressure Ratio ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Combustion Engines ◽  
One Dimensional ◽  
Performance Map

Zero-dimensional/one-dimensional computational fluid dynamics codes are used to simulate the performance of complete internal combustion engines. In such codes, the operation of a turbocharger compressor is usually addressed employing its performance map. However, simulation of engine transients may drive the compressor to work at operating conditions outside the region provided by the manufacturer map. Therefore, a method is required to extrapolate the performance map to extended off-design conditions. This work examines several extrapolating methods at the different off-design regions, namely, low-pressure ratio zone, low-speed zone and high-speed zone. The accuracy of the methods is assessed with the aid of compressor extreme off-design measurements. In this way, the best method is selected for each region and the manufacturer map is used in design conditions, resulting in a zonal extrapolating approach aiming to preserve accuracy. The transitions between extrapolated zones are corrected, avoiding discontinuities and instabilities.

Sign in / Sign up

Export Citation Format

Share Document