scholarly journals Fatigue analysis of the connecting rod in internal combustion engines

2019 ◽  
Vol 485 ◽  
pp. 012008
Author(s):  
M Frătița ◽  
F Popescu ◽  
K Uzuneanu ◽  
V Mereuță ◽  
I Ion
Keyword(s):  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Fatigue Analysis ◽  
Combustion Engines ◽  
Connecting Rod

scholarly journals The influence of centrial forces on crankshaft bearing lubrication is in emergency modes of the engine of the car

2021 ◽  
Vol 12 (2) ◽  
pp. 112-121
Author(s):  
Oleksandr Khrulev ◽  
◽  
Olexii Saraiev ◽  
Iryna Saraieva ◽  
◽  
...  
Keyword(s):  
Internal Combustion Engines ◽  
Operating Mode ◽  
Internal Combustion ◽  
Technical Condition ◽  
Operating Conditions ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Oil Supply ◽  
Technical Expert ◽  
The Difference

The analysis of the crankshaft bearing condition of the automotive internal combustion engines in the case of insufficiency and breakage of oil supply to them is carried out. It is noted that this fault is one of the most common causes of damage to rubbing pairs in operation. At the same time, the different groups of bearings are often damaged, which cannot be explained within the framework of existing models of plain bearing lubrication. The objective of the work is to develop a mathematical model of oil supply to connecting rod bearings in emergency mode, taking into account the characteristic features of the bearing design. The model also, depending on the nature of the damage, should help to determine and explain the causes of bearing failures if they occur in different modes when operating conditions are broken. A computational model has been developed that makes it possible to assess the effect of design differences in the features of oil supply and the action of the centrifugal forces during crankshaft rotation on the oil column in the lubrication hole where oil is supplied to the conrod bearing. Calculations of the change in time of the oil supply pressure to the connecting rod bearings for the various designs of the crankshaft lubrication holes have been performed. It is shown that, depending on the operating mode of the engine and its design, the oil pressure in front of the connecting rod bearings does not disappear immediately after oil supply failure to crankshaft. Moreover, the lower the crankshaft speed is, the longer the lubrication of the conrod bearings will continue. The calculation results are confirmed by the data of the expert studies of the engine technical condition, in which the crankshaft was wedged in the damaged main bearings was found in the absence of serious damage to the connecting rod ones. It has been found that such features of the damage correspond to an rapid breakage of the oil supply to the crankshaft in the case of such operational damage as the oil pump and pressure reducing valve failure, the oil filter seal and oil pan destruction, etc. The developed model explains the difference in lubrication conditions and in the damage feature to the main and connecting rod bearings in the emergency cases of the oil supply breakage, which are observed during operation, and helps to clarify the failure causes. This makes it possible to use the model and the obtained data when providing auto technical expert studies of the failure causes of automobile internal combustion engines This makes it possible to use the model and the obtained data when providing auto technical expert studies of the failure causes of automobile internal combustion engines when the operating conditions are broken.

scholarly journals SOME ASPECTS OF INFLUENCE OF THE CONNECTING ROD DESIGN ON THE OUTPUT PARAMETERS OF HIGH-SPEED INTERNAL COMBUSTION ENGINES

2020 ◽  
Vol 0 (1(86)) ◽  
Author(s):  
Сергій Олексійович Дмитрієв ◽  
Олександр Едуардович Хрулєв
Keyword(s):  
High Speed ◽  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Connecting Rod

An Optimum Flexible Linkage Design of a Fully Variable Electromechanical Valve Actuation System for Internal Combustion Engines

2011 ◽  
Vol 133 (12) ◽  
Author(s):  
D. T. Hossein Rokni ◽  
Rudolf J. Seethaler ◽  
Abbas S. Milani
Keyword(s):  
Internal Combustion Engines ◽  
Mechanical Design ◽  
Design Procedure ◽  
Experimental Tests ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Actuation System ◽  
Flexible Linkage ◽  
Valve Actuation

In this study, the mechanical design of a fully flexible valve actuation system (FFVA) for intake valves of naturally aspirated internal combustion engines is optimized. The original FFVA design used a connecting rod in order to transform the rotating motion of the actuator to translating motion of the valve. In the improved design introduced here, the connecting rod is replaced by a flexible linkage. This step is taken in order to eliminate wear and play in the mechanical connections. A detailed design procedure is presented to optimize the heavy fatigue load on this element. Simulations and experimental tests are carried out in order to validate the system performance. It is shown that valve trajectory and energy consumption of the actuation system obtained by simulations are consistent with those observed experimentally. The present redesigned FFVA system then provides more reliable valve motion than previously shown designs.

scholarly journals A Wear Analysis Carried On Connecting Rod Bearings From Internal Combustion Engines

2020 ◽  
Author(s):  
Juan Rodrigo Laguna-Camacho ◽  
Silvia M. Sánchez-Yáñez ◽  
Gabriel Juárez-Morales ◽  
Maria I. Cruz-Orduña ◽  
Luz M. Ramos-González ◽  
...  
Keyword(s):  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Wear Analysis

scholarly journals Desarrollo didáctico complementario de las expresiones analíticas de las acciones de sacudimiento en las máquinas de combustión interna

2020 ◽  
pp. 16-26
Author(s):  
Benjamín Vázquez-González ◽  
Homero Jiménez Rabiela ◽  
José Luis Ramírez Cruz ◽  
Pedro García Segura
Keyword(s):  
Internal Combustion Engine ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Dynamic Equations ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Repetitive Movement ◽  
Main Interest

The study of the forces and the pairs of shaking that appear in mechanisms, are of main interest in the study of the dynamics of the internal combustion engines. An internal combustion engine is modeled from a particular arrangement of a set of mechanisms of the connecting-rod-crank type. During the performance of the internal combustion engine, the repetitive movement of the slide or piston induces accelerations and forces that are transmitted and distributed between the connecting rod and the crank or crankshaft. When the crankshaft is subjected to the components of the forces induced by the piston, the shaking torques are generated in turn. The purpose of the analysis of the pairs of shaking is to determine the dynamic values of the counterweights that must be added to each mechanism, with the aim of reducing the set of shaking actions. In the traditional bibliography in which the dynamic equations are presented, the complete analytical developments are not always presented; there are references that present partial results, in this work the algebraic developments are presented that allow to validate the correspondence between the expressions of different bibliographic sources in the teaching of these subjects.

scholarly journals Estimation of Design Parameters of the Crank-Connecting Rod Mechanism of Engines for Mobile Agricultural Machines

2021 ◽  
Vol 37 ◽  
pp. 00076
Author(s):  
F. Khaliullin ◽  
G. Pikmullin ◽  
A. Nurmiev ◽  
M. Lushnov
Keyword(s):  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Design Model ◽  
Design Parameters ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Mass Model ◽  
Calculation Results ◽  
The Masses ◽  
Lumped Masses

An accurate choice of the design model of the crank-connecting rod mechanism of piston internal combustion engines affects the accuracy of the calculation results and their complexity. At present, most of scientists and technicians choose a two-mass design model to analyze the operation of the crankconnecting rod mechanism. The model considers only the rotational and reciprocating movements of two masses, which are connected by a rigid weightless rod. This model significantly simplifies the calculations, neglects the elastic deformations of the parts of the crank-connecting rod mechanism, and eliminates the need for compiling the equations of dynamics in partial derivatives. However, the model has a number of drawbacks. The calculation results obtained using the two-mass model exhibit significant errors, which mainly depend on the design features of the connecting rod assembly. The paper discusses multi-mass design models, where the connecting rod assembly can comprise several lumped masses located along its length. In this case, the plane-parallel motion of these masses is added. The masses have weightless and absolutely rigid bonds. Forces and moments acting on the piston assembly and the crank are calculated according to the equations compiled. Comparison of the calculation results with the results obtained for a two-mass model can be used to determine errors and choose a design model that provides the required accuracy. The considered design model is of interest to engineers and technicians engaged in the design and calculation of the crank-connecting rod mechanism of piston internal combustion engines.

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