THE OXIDATION, IGNITION, AND DETONATION OF FUEL VAPORS AND GASES: IV. THE CAUSE OF DETONATION OR COMBUSTION KNOCK IN ENGINES

1948 ◽  
Vol 26f (5) ◽  
pp. 228-240 ◽  
Author(s):  
R. O. King
Keyword(s):  
Internal Combustion Engine ◽  
Experimental Evidence ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combustible Mixture ◽  
Lubricating Oil ◽  
Nuclear Theory ◽  
General Application ◽  
Combustion Knock ◽  
Permanent Gases

A nuclear theory of self-ignition is described which is based on the substitution of finely divided carbon for the nuclear drops of the Callendar theory. The finely divided carbon appears in the gaseous combustible mixture in the engine as a result of pyrolysis of the lubricating oil or of the fuel. The theory is therefore of general application and can be applied to explain combustion knock or detonation when permanent gases such as hydrogen as well as hydrocarbon vapors are used as fuel for the carburetor type of internal combustion engine. The theory is supported by experimental evidence quoted mainly from earlier publications and is intended as a working hypothesis for further confirmatory experiments.

Impact of the Piston Secondary Motion on its Slap Force

2014 ◽  
Vol 553 ◽  
pp. 582-587
Author(s):  
Bao Cheng Zhang ◽  
Tong Li ◽  
Hai Fei Zhan ◽  
Yuan Tong Gu
Keyword(s):  
Theoretical Model ◽  
Boundary Conditions ◽  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Cylinder Liner ◽  
Internal Combustion ◽  
Lubricating Oil ◽  
Actual Condition ◽  
Piston Skirt ◽  
Secondary Motion

A theoretical model is developed for the analysis of piston secondary motion. Based on this model, the slap force of a specific L6 diesel engine was compared when considering different boundary conditions, such as lubricating oil on cylinder liner, surface roughness, deformation of cylinder liner and piston skirt. It is concluded that it is necessary to consider the secondary motion of piston in the analysis of the inner excitation for an internal combustion engine. A more comprehensive consideration of the boundary condition (i.e., more close to the actual condition) will lead to a smaller maximum slap force, and among all boundary conditions considered in this paper, the structural deformation of the piston skirt and cylinder liner is the most influential factor. The theoretical model developed and findings obtained in this study will benefit the future analysis and design of advanced internal combustion engine structures.

THE OXIDATION, IGNITION AND DETONATION OF FUEL VAPORS AND GASES: V. THE HYDROGEN ENGINE AND THE NUCLEAR THEORY OF IGNITION

1948 ◽  
Vol 26f (6) ◽  
pp. 264-276 ◽  
Author(s):  
R. O. King ◽  
W. A. Wallace ◽  
B. Mahapatra
Keyword(s):  
Normal Condition ◽  
Compression Ratio ◽  
Gaseous Mixture ◽  
Combustible Mixture ◽  
The Body ◽  
Lubricating Oil ◽  
Nuclear Theory ◽  
Combustion Knock ◽  
Ignition And Combustion ◽  
Hydrocarbon Vapor

It should not be possible, according to the nuclear theory of ignition, stated in Part IV, to obtain ignition in the body of a gaseous combustible mixture by any method of heating if it remain truly homogeneous while the temperature is raised. Such mixtures cease to be homogeneous when heated by sudden compression to the temperatures required for ignition because of the formation of finely divided carbon by pyrolysis of lubricating oil or of hydrocarbon vapor. The finely divided carbon provides nuclear centers of ignition in the gaseous mixture. Ignition due to finely divided carbon produced by pyrolysis of the lubricant is demonstrated by experiments with hydrogen as the fuel for a C.F.R. engine. The usual pre-ignition and severe knocking were obtained when the engine in normal condition was run on hydrogen, and it was impossible, as previously found by others, to use any but weak mixtures even at low compression ratios. When however the combustion space was decarbonized and thereafter maintained reasonably clear of fluffy carbon, hydrogen could be used as the sole fuel at any compression ratio up to the limit of 10:1 possible with the engine, and at any mixture strength ranging from very weak to very rich, while power output varied accordingly. Conversely pre-ignition and combustion knock reappeared when carbon dust was admitted with the combustible mixture.

The Simple Model of the Oil Film Thickness between Piston Ring and Cylinder

2010 ◽  
Vol 97-101 ◽  
pp. 1239-1242
Author(s):  
De Liang Liu ◽  
Hui Biao Lu ◽  
C.G. Sun
Keyword(s):  
Film Thickness ◽  
Internal Combustion Engine ◽  
Piston Ring ◽  
Reynolds Equation ◽  
Combustion Engine ◽  
Friction Pair ◽  
Internal Combustion ◽  
Theoretical Research ◽  
Lubricating Oil ◽  
Oil Film

Piston ring-cylinder is one of the most important friction pair of internal combustion engine，the lubricating state between them has decided internal combustion engine lubrication quality. So the theoretical research to the lubricating characteristics of the piston-ring group, especially the calculation of the lubricating oil film thickness is very important. The oil film thickness between piston-ring and cylinder is studied by calculation method. The calculation program is developed with average Reynolds equation taken the surface topography, viscosity-temperature effect, viscosity-pressure effect, extrusion effect and other factors into account. The position of oil outlet point is preinstalled, the full lubrication is assumed, and the Reynolds equation is solved by full pivot element gausses elimination approach, so the iterative course and calculation workload are reduced, and a great lot of the calculating time is saved, the oil film thickness of full period can be more accurately predicted by the ordinary PC within 30 minutes, which can supply quick effective evidence for next calculation and analysis.

Sign in / Sign up

Export Citation Format

Share Document