Elastic Connecting-Rod Bearing With Piezoviscous Lubricant: Analysis of the Steady-State Characteristics

1979 ◽  
Vol 101 (2) ◽  
pp. 190-197 ◽  
Author(s):  
B. Fantino ◽  
J. Frene ◽  
J. Du Parquet
Keyword(s):  
Steady State ◽  
Film Thickness ◽  
Plane Elasticity ◽  
Operating Conditions ◽  
Maximum Pressure ◽  
Connecting Rod ◽  
Oil Film ◽  
Lubricant Analysis ◽  
Relative Eccentricity ◽  
Dimensional Equation

The effect of the deformation of an automotive connecting-rod on the oil film characteristics are studied. The simultaneous elastic deformation and pressure distribution are obtained by iterative methods in steady-state conditions under realistic speeds and loads (5500 rpm, 25,000 N). Plane elasticity relations are used in this study. The following parameters are investigated: —bearing characteristics: bearing thickness B and bearing clearance C, —operating conditions: journal speed N and applied load W, —lubricant: viscosity μ0 and piezoviscous coefficient α. As a result of the deformation, the maximum pressure and the attitude angle are decreased and the relative eccentricity is greatly increased. The minimum oil film thickness is slightly but systematically decreased. The piezoviscosity effect is noticeable only at high loads: it increases slightly the oil film thickness and the maximum pressure. An empirical dimensional equation for the minimum oil film thickness hm is derived numerically for the bearing considered. Thus: hm∼μ0NW0.5(1+0.06108α)B0.12C0.09

Steady State Performance Characteristics of a Tilting Pad Thrust Bearing

2000 ◽  
Vol 123 (3) ◽  
pp. 608-615 ◽  
Author(s):  
Sergei B. Glavatskikh
Keyword(s):  
Steady State ◽  
Film Thickness ◽  
Thrust Bearing ◽  
Operating Conditions ◽  
Performance Characteristics ◽  
Shaft Speed ◽  
Oil Film ◽  
Tilting Pad ◽  
Bearing Load ◽  
Steady State Performance

The paper reports results of the experimental investigation into the steady state performance characteristics of a tilting pad thrust bearing typical of design in general use. Simultaneous measurements are taken of the pad and collar temperatures, the pressure distributions, oil film thickness, and power loss as a function of shaft speed, bearing load, and supplied oil temperature. The effect of operating conditions on bearing performance is discussed. A small radial temperature variation is observed in the collar. A reduction in minimum oil film thickness with load is approximately proportional to p−0.6, where p is an average bearing pressure. It has also been found that the oil film pressure profiles change not only due to the average bearing load but also with an increase in shaft speed and temperature of the supplied oil.

The dynamic simulation and experiment of bearing capacity of multi oil cushion static bearing with double rectangular cavities

2019 ◽  
Vol 71 (9) ◽  
pp. 1072-1079
Author(s):  
Yanqin Zhang ◽  
Jichang Sun ◽  
Pengrui Kong ◽  
Xiangbin Kong ◽  
Xiaodong Yu
Keyword(s):  
Film Thickness ◽  
Bearing Capacity ◽  
Dynamic Simulation ◽  
Working Conditions ◽  
Operating Conditions ◽  
Dynamic Mesh ◽  
Maximum Pressure ◽  
Inlet Flow ◽  
Content Type ◽  
Oil Film

Purpose The purpose of the paper is to analyze the bearing capacity of hydrostatic bearing during the change of film thickness under different working conditions and to improve the processing efficiency and precision of equipment. Design/methodology/approach In this study, Q1-205 double rectangular cavity hydrostatic thrust bearing is selected as the research object. The dynamic mesh method and ANSYS/FLUENT software are used to simulate the curves of oil film thickness and oil pressure under different operating conditions. Finally, the change of pressure in the oil cavity at different operating speeds under a certain inlet flow rate was tested through design experiments. Findings When the film thickness was thick, the maximum pressure in the oil cavity at different inlet velocities showed little difference. With a larger inlet flow, the maximum pressure in the oil cavity was higher. The pressure at the edge of the oil seal was linearly distributed. The oil pressure in the downstream side was greater than that in the counter flow side. When the working pressure was low, the pressure in the oil cavity slightly decreased with the increase of working speed. Moreover, the pressure loss at high speed was considerable. Originality/value Based on the lubrication theory, the mathematical model of the bearing oil film was set up. The bearing capacity equation of the hydrostatic cavity was derived. The double-rectangular-annular hydrostatic guides studied in this paper have not been reported in previous research literature and the method of dynamic mesh dynamic simulation of variable viscosity is seldom studied before. The bearing characteristics and the change of oil film thickness under different working conditions have been studied systematically and comprehensively. The theoretical analysis results are basically consistent with the experimental results.

Influence of Engine Inertia Forces on Minimum Film Thickness in Con-Rod Big-End Bearings

1966 ◽  
Vol 181 (1) ◽  
pp. 749-764 ◽  
Author(s):  
F. A. Martin ◽  
J. F. Booker
Keyword(s):  
Film Thickness ◽  
General Purpose ◽  
Operating Conditions ◽  
Eccentricity Ratio ◽  
Connecting Rod ◽  
Oil Film ◽  
Minimum Film Thickness ◽  
Method Of Solution ◽  
Mobility Method ◽  
Inertia Forces

In the design of dynamically loaded bearings, the journal eccentricity will vary in magnitude and direction throughout the loading cycle. One of the designer's interests is in the trends of maximum eccentricity ratio and the corresponding oil film thickness for various bearing and engine conditions. From experience with journal eccentricity predictions for big-end bearings it has been found that the eccentricity ratio in the bearing due to the peak firing load seldom exceeds that due to the inertia load alone (although this load is smaller). Therefore, as an approximation, it is thought justifiable to neglect the gas forces. The maximum eccentricity ratio for numerous inertia load cycles was computed based on the numerical mobility method of solution (1)†; because of its simplicity and as only trends were required, the short bearing solution was used. The results of this study applied to big-end bearings show how the reciprocating and rotating masses affect the maximum eccentricity ratio. Also the effect of the ratio of crank radius to con-rod length is investigated, as is the effect of change in bearing clearance. A useful general-purpose graph is presented which will enable the designer to estimate comparative values of minimum oil film thickness over a practical range of bearing operating conditions. It is emphasized that the value of oil film thickness by itself may not be very helpful if used in absolute terms, as its correctness will depend on the assumptions made. The general results will, however, be useful if used as a comparator, and should give some guidance on how to improve the performance of connecting-rod big-end bearings.

Studying Systems of Stabilization of Supports in Hydrostatic Machine Tool

2012 ◽  
Vol 622-623 ◽  
pp. 489-493
Author(s):  
Iskander Beisembetov ◽  
Sabyi Ussupov ◽  
Bakhyt Absadykov ◽  
Beken Arymbekov ◽  
Birzhan Bektibay
Keyword(s):  
Film Thickness ◽  
Machine Tools ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Operational Parameters ◽  
Automatic Stabilization ◽  
Design Elements ◽  
Oil Film ◽  
Hydrostatic Bearing ◽  
Automatic Control Systems

Development relevance to improve the operational parameters of the support units of machine tools in their design elements is introduced that increase the rigidity of the components, their carrying capacity, damp occurring vibrations in the process, the coefficient of performance (COP), smoothness of motion, positioning accuracy, reducing the wear of their working surfaces and maintain the original accuracy. A number of engineering development [1], [2], aimed at improving the above characteristics of the machine by changing and improving design of reference nodes used in these rails rolling bearings, aerostatic and hydrostatic guides, as well as the use of automatic control systems of its basic parameters, determine its quality. However, in some operating conditions in which errors occur, mainly due to the instability of oil-film thickness (gap) between the mobile and immobile elements of the hydrostatic bearing. For high accuracy requirements it will negatively affect the quality of machined parts and equipment performance. On this basis, it becomes apparent urgency of the problem of automatic stabilization of oil-film thickness (gap) in the IR. To ensure high precision equipment to improve power system hydrostatic bearing units of machine tools. This, in turn, creates the prerequisite for the development of stabilization systems of the gap in the hydrostatic bearing, with the help of which the thickness of oil layer in them would be kept constant even with significant dynamic load on the support.

Comprehensive design methodology for an engine journal bearing

2000 ◽  
Vol 214 (4) ◽  
pp. 401-412 ◽  
Author(s):  
H Hirani ◽  
K Athre ◽  
S Biswas
Keyword(s):  
Film Thickness ◽  
High Speed ◽  
Design Methodology ◽  
Design Procedure ◽  
Maximum Pressure ◽  
Connecting Rod ◽  
Automotive Engine ◽  
Reciprocating Engine ◽  
High Power Output ◽  
Minimum Film Thickness

The trend towards high power output, high speed and low power loss in engines requires a better understanding of bearing behaviour. Research in this area is directed more towards different aspects involved in bearing analyses, rather than providing a comprehensive guideline on design of bearing. This effort compiles the design methodology for selection of diametral clearance and bearing length by limiting the minimum film thickness, maximum pressure and temperature. The design procedure is summarized on the basis of the existing rapid bearing analyses for evaluation of the journal trajectory, minimum film thickness and maximum pressure and simplified thermal analysis. A flow chart is provided for step-by-step bearing design. Finally, two case studies of engine bearings are described: one investigates the VEB bigend connecting-rod bearing for a large industrial reciprocating engine and the other a main crankshaft bearing for an automotive engine. The methodology translates into easy-to-use expressions and the overall procedure is outlined, using practical data to demonstrate how this can be employed effectively by users.

An Experimental Analysis of Misalignment Effects on Hydrodynamic Plain Journal Bearing Performances

2001 ◽  
Vol 124 (2) ◽  
pp. 313-319 ◽  
Author(s):  
J. Bouyer ◽  
M. Fillon
Keyword(s):  
Film Thickness ◽  
Journal Bearing ◽  
Hydrodynamic Pressure ◽  
Operating Conditions ◽  
Temperature Fields ◽  
Maximum Pressure ◽  
Minimum Film Thickness ◽  
Oil Flow ◽  
Hydrodynamic Effects

The present study deals with the experimental determination of the performance of a 100 mm diameter plain journal bearing submitted to a misalignment torque. Hydrodynamic pressure and temperature fields in the mid-plane of the bearing, temperatures in two axial directions, oil flow rate, and minimum film thickness, were all measured for various operating conditions and misalignment torques. Tests were carried out for rotational speeds ranging from 1500 to 4000 rpm with a maximum static load of 9000 N and a misalignment torque varying from 0 to 70 N.m. The bearing performances were greatly affected by the misalignment. The maximum pressure in the mid-plane decreased by 20 percent for the largest misalignment torque while the minimum film thickness was reduced by 80 percent. The misalignment caused more significant changes in bearing performance when the rotational speed or load was low. The hydrodynamic effects were then relatively small and the bearing offered less resistance to the misalignment.

Thermal Elastohydrodynamic Lubrication of Rider Rings

1984 ◽  
Vol 106 (4) ◽  
pp. 492-498 ◽  
Author(s):  
Vilmos Simon
Keyword(s):  
Film Thickness ◽  
Numerical Solution ◽  
Temperature Variation ◽  
Elastohydrodynamic Lubrication ◽  
Operating Conditions ◽  
Performance Characteristics ◽  
Oil Film ◽  
The Real ◽  
Ring Geometry

The full thermal elastohydrodynamic analysis of the lubrication of rider rings is presented. A numerical solution of the coupled Reynolds, elasticity, energy, and Laplace’s equations for the oil film thickness, pressure, and temperature and rider rings temperatures is obtained. The temperature variation across the oil film is included. The real rider ring geometry is treated. The effect of the operating conditions on the performance characteristics is discussed.

Summary 1: The Influence of Engine Component Inertia Forces on Minimum Oil Film Thickness in Connecting Rod Big-End Bearings

1966 ◽  
Vol 181 (2) ◽  
pp. 155-155
Author(s):  
J. F. Booker ◽  
F. A. Martin
Keyword(s):  
Film Thickness ◽  
Graphical Form ◽  
Load Carrying Capacity ◽  
Eccentricity Ratio ◽  
Connecting Rod ◽  
Oil Film ◽  
First Approximation ◽  
Load Carrying ◽  
The Many ◽  
Inertia Forces

when Designing steadily loaded bearings the designer can usually predict the position of the journal centre quite easily with the aid of one of the many load carrying capacity/eccentricity relationships available. With dynamically loaded bearings, however, the journal path will vary in magnitude and direction throughout the loading cycle and one of the designer's interests is in the trends of maximum eccentricity ratio and the corresponding oil film thickness for various bearing and engine conditions. From experience with journal path predictions for big-end bearings it has been found that the eccentricity ratio in the bearing due to the peak firing load seldom exceeds that obtained by the inertia load loop (although this load is smaller) and therefore, as a first approximation, it is thought justifiable to neglect the gas forces. The results of this inertia study (numerical solution) applied to big-end bearings are presented in a general graphical form. Further work can be carried out on the same basis for main bearings, but this is more difficult to present in a general fashion as there are many more variables to consider, such as the phasing and magnitude of the crank out of balance and the firing order. This report therefore concentrates on the first step, i.e. that of big-end bearings.

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