Hybrid prediction method of load-carrying capacity considering boundary condition of expansion joint sleeve and rotation angle of spindle

2021 ◽  
Vol 35 (10) ◽  
pp. 4605-4615
Author(s):  
Yongqiang Guan ◽  
Jianmei Wang ◽  
Ke Ning ◽  
Dingbang Hou
Keyword(s):  
Boundary Condition ◽  
Carrying Capacity ◽  
Rotation Angle ◽  
Prediction Method ◽  
Load Carrying Capacity ◽  
Expansion Joint ◽  
Hybrid Prediction ◽  
Load Carrying

scholarly journals Influence of boundary condition and stiffener type on collapse behaviours of stiffened panels under longitudinal compression

2019 ◽  
Vol 11 (10) ◽  
pp. 168781401988476
Author(s):  
Jin Pan ◽  
Na Li ◽  
Zhao Jun Song ◽  
Ming Cai Xu
Keyword(s):  
Boundary Condition ◽  
Finite Element ◽  
Carrying Capacity ◽  
Biaxial Stress ◽  
Stiffened Panel ◽  
Load Carrying Capacity ◽  
Longitudinal Compression ◽  
Stiffened Panels ◽  
Biaxial Stress State ◽  
Load Carrying

A series of stiffened panels with different dimensions and types of stiffener are simulated under longitudinal compression in finite element code ANSYS. Two bays/spans model with periodic boundary condition is adopted to consider the influence of neighbouring members. The stiffened panel adopted in the finite element mode is generally cut from the deck or bottom of a ship hull girder, and thus, the constraint on their edges depends to some extent on the relative structural response of the adjacent members. Hence, to understand the effects of constraint condition on the collapse behaviour, an extensive parametric study is carried out, employing a wide geometrical range for bulk carrier and very large crude carrier. Moreover, considering various collapse modes, the load-carrying capacities of the stiffened panels are also investigated for various stiffener types. It is found that the biaxial stress state caused by longitudinal constraint could increase or decrease the load-carrying capacity of the stiffened panel, which depends on the collapse mode and should be noticed. The transverse constraint on the longitudinal edges could cause biaxial stress state, which might increase or decrease the load-carrying capacity of the stiffened panel, which depends on the collapse modes.

Paper 14: Hydrodynamic Lubrication of Lightly Loaded Finite Cylinders

1966 ◽  
Vol 181 (15) ◽  
pp. 112-116
Author(s):  
R. J. Boness
Keyword(s):  
Boundary Condition ◽  
Boundary Conditions ◽  
Velocity Gradient ◽  
Carrying Capacity ◽  
Hydrodynamic Lubrication ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Fluid Properties ◽  
Theoretical Results ◽  
Finite Cylinders

Theoretical results of the load-carrying capacity of lightly loaded finite cylinders indicate that the effect of side leakage can be secondary to upstream boundary condition considerations. Neglecting side leakage the calculations are extended to cover the experimental results of Crook into the régime where the fluid properties are pressure dependent. The results support the adoption of the new velocity and velocity gradient boundary conditions suggested by Lauder.

Investigating the effect of different slip zone locations on the lubrication performance of textured journal bearings

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mohammad Arif ◽  
Saurabh Kango ◽  
Dinesh Kumar Shukla
Keyword(s):  
Boundary Condition ◽  
Carrying Capacity ◽  
Slip Boundary Condition ◽  
Journal Bearings ◽  
Load Carrying Capacity ◽  
Inflow Rate ◽  
Content Type ◽  
Surface Textures ◽  
Slip Boundary ◽  
Load Carrying

Purpose This study aims to purpose the suitable location of slip boundary condition and microscale surface textures to enhance the tribological performance of the hydrodynamic journal bearings. Design/methodology/approach Mass conserving Elrod cavitation algorithm with considering slip boundary condition has been used for predicting the static performance characteristics (load carrying capacity, coefficient of friction and volumetric inflow rate) of finite cylindrical shape textured journal bearings. Findings It has been observed that the full textured bearing with slip boundary condition in between 0°–180° circumferential region gives a significant reduction in the lubricant rupture zone. However, the introduction of textures up to the interface of slip and the no-slip region is increasing the load-carrying capacity and reduces the shear stress. This reduction in shear stress with combined slip and surface textures is effective in increasing the volumetric inflow rate of the lubricant. Practical implications The combined effect of slip boundary condition and surface texturing is increasing the scope of liquid lubricants in hydrodynamic journal bearings and further contributing toward the development of small-scale rotating machines. Originality/value The study related to the use of mass conserving Elrod cavitation algorithm for finding the optimum location of slip and surface texture zones has been found rare in the literature. Previous studies show that the mass conserving Elrod cavitation algorithm gives realistic results for textured bearings and its findings show good agreement with the experimental observations.

Effect of large-area texture/slip surface on journal bearing considering cavitation

2015 ◽  
Vol 67 (3) ◽  
pp. 216-226 ◽  
Author(s):  
Qiyin Lin ◽  
Zhengying Wei ◽  
Ning Wang ◽  
Wei Chen
Keyword(s):  
Boundary Condition ◽  
Carrying Capacity ◽  
Journal Bearing ◽  
Slip Surface ◽  
Load Carrying Capacity ◽  
Large Area ◽  
Texture Surface ◽  
Content Type ◽  
Load Carrying ◽  
The Impact

Purpose – The purpose of this paper is to study the influence of large-area texture/slip surface, especially the area and position of large-area texture surface on journal bearing, and improve the tribological performances of journal bearing. Design/methodology/approach – A modified texture/slip numerical boundary condition with double parameters is presented and is applied onto the region where surface textures locate to represent the impact of actual texture/slip surface. A phase change condition is used to analyze cavitation phenomena. Findings – The global/cumulative texture effect can be represented by applying texture/slip condition onto the region where it locates. The area and position of texture/slip surface would significantly affect the cavitation and load-carrying capacity. Texture/slip surface would not affect the pressure and load-carrying capacity when it locates at cavitation zone. The effect of texture/slip surface on load-carrying capacity would be beneficial if it locates at the pressure rise region, but its effect would be adverse if it locates at the pressure drop region. Well-designed texture/slip surface can improve tribological performances. Originality/value – The developed texture/slip boundary condition can be a suitable and useful tool to analyze the effect of large-area texture/slip surface and especially to optimize the area and position of large-area texture surface. This approach can be complementary to conventional approach which is used to analyze the influence of textures’ real configurations and parameters.

Isoviscous Lubrication of Rigid Cylinders: A Modification to Classical Theory

1966 ◽  
Vol 8 (3) ◽  
pp. 276-283 ◽  
Author(s):  
R. J. Boness
Keyword(s):  
Boundary Condition ◽  
Film Thickness ◽  
Boundary Conditions ◽  
Classical Theory ◽  
Velocity Gradient ◽  
Carrying Capacity ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
The Difference ◽  
Theoretical Results

Measurements of oil film thickness between lightly loaded lubricated discs show that the original theory of Martin over-estimates the film thickness by between 100 and 800 per cent, depending on the ratio of the difference of the surface velocities and their sum. Theoretical results indicate that the upstream boundary condition could account for the discrepancy between the experimental results and the Martin theory. A procedure for the calculation of load-carrying capacity of lightly loaded cylinders based upon new upstream velocity and velocity gradient boundary conditions suggested by Lauder is presented.

The Lubrication of Lightly Loaded Cylinders in Combined Rolling, Sliding, and Normal Motion—Part I: Theory

1976 ◽  
Vol 98 (4) ◽  
pp. 509-516 ◽  
Author(s):  
D. Dowson ◽  
P. H. Markho ◽  
D. A. Jones
Keyword(s):  
Boundary Condition ◽  
Steady State ◽  
Film Thickness ◽  
Carrying Capacity ◽  
Dimensionless Parameter ◽  
Load Carrying Capacity ◽  
State Problem ◽  
Load Carrying ◽  
Minimum Film Thickness ◽  
Steady State Problem

The problem considered in this paper is that of the lubrication of rigid cylindrical solids by an isoviscous lubricant. The steady-state problem has been studied by several authors, but the present analysis explores the effect of non-steady-state conditions arising from combined ‘normal’ and ‘entraining’ motion. It is shown that the major bearing performance characteristics can be accounted for by means of a dimensionless parameter (q) involving the ‘normal’ and ‘entraining’ velocities, the minimum film thickness and the radius of a geometrically equivalent cylinder near a plane. The results are represented graphically and by a set of convenient polynomials in (q). The influence of the cavitation boundary condition is considered and it is shown that sinusoidal ‘normal’ motion superimposed upon ‘entraining’ action can lead to a substantial increase in the nett load carrying capacity.

Influence of Yield Strength Variability over Cross-Section to Steel Beam Load-Carrying Capacity

2005 ◽  
Vol 10 (2) ◽  
pp. 151-160 ◽  
Author(s):  
J. Kala ◽  
Z. Kala
Keyword(s):  
Yield Strength ◽  
Cross Section ◽  
Carrying Capacity ◽  
Bending Moment ◽  
Statistical Characteristics ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Strength Variability ◽  
Hot Rolled ◽  
Hot Rolled Steel

Authors of article analysed influence of variability of yield strength over cross-section of hot rolled steel member to its load-carrying capacity. In calculation models, the yield strength is usually taken as constant. But yield strength of a steel hot-rolled beam is generally a random quantity. Not only the whole beam but also its parts have slightly different material characteristics. According to the results of more accurate measurements, the statistical characteristics of the material taken from various cross-section points (e.g. from a web and a flange) are, however, more or less different. This variation is described by one dimensional random field. The load-carrying capacity of the beam IPE300 under bending moment at its ends with the lateral buckling influence included is analysed, nondimensional slenderness according to EC3 is λ¯ = 0.6. For this relatively low slender beam the influence of the yield strength on the load-carrying capacity is large. Also the influence of all the other imperfections as accurately as possible, the load-carrying capacity was determined by geometrically and materially nonlinear solution of very accurate FEM model by the ANSYS programme.

Fuzzy Sets Theory in Comparison with Stochastic Methods to Analyse Nonlinear Behaviour of a Steel Member under Compression

2005 ◽  
Vol 10 (1) ◽  
pp. 65-75 ◽  
Author(s):  
Z. Kala
Keyword(s):  
Fuzzy Sets ◽  
Carrying Capacity ◽  
Stochastic Methods ◽  
Nonlinear Behaviour ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Input Parameters ◽  
Stochastic Solution ◽  
Fuzzy Solution ◽  
Sets Theory

The load-carrying capacity of the member with imperfections under axial compression is analysed in the present paper. The study is divided into two parts: (i) in the first one, the input parameters are considered to be random numbers (with distribution of probability functions obtained from experimental results and/or tolerance standard), while (ii) in the other one, the input parameters are considered to be fuzzy numbers (with membership functions). The load-carrying capacity was calculated by geometrical nonlinear solution of a beam by means of the finite element method. In the case (ii), the membership function was determined by applying the fuzzy sets, whereas in the case (i), the distribution probability function of load-carrying capacity was determined. For (i) stochastic solution, the numerical simulation Monte Carlo method was applied, whereas for (ii) fuzzy solution, the method of the so-called α cuts was applied. The design load-carrying capacity was determined according to the EC3 and EN1990 standards. The results of the fuzzy, stochastic and deterministic analyses are compared in the concluding part of the paper.

Pavement Damage Due to Conventional and New Generation of Wide-Base Super Single Tires

2005 ◽  
Vol 33 (4) ◽  
pp. 210-226 ◽  
Author(s):  
I. L. Al-Qadi ◽  
M. A. Elseifi ◽  
P. J. Yoo ◽  
I. Janajreh
Keyword(s):  
Carrying Capacity ◽  
Material Properties ◽  
Three Dimensional ◽  
Fe Analysis ◽  
Load Carrying Capacity ◽  
Inflation Pressure ◽  
3D Finite Element ◽  
Load Carrying ◽  
Pavement Damage ◽  
New Generation

Abstract The objective of this study was to quantify pavement damage due to a conventional (385/65R22.5) and a new generation of wide-base (445/50R22.5) tires using three-dimensional (3D) finite element (FE) analysis. The investigated new generation of wide-base tires has wider treads and greater load-carrying capacity than the conventional wide-base tire. In addition, the contact patch is less sensitive to loading and is especially designed to operate at 690kPa inflation pressure at 121km/hr speed for full load of 151kN tandem axle. The developed FE models simulated the tread sizes and applicable contact pressure for each tread and utilized laboratory-measured pavement material properties. In addition, the models were calibrated and properly validated using field-measured stresses and strains. Comparison was established between the two wide-base tire types and the dual-tire assembly. Results indicated that the 445/50R22.5 wide-base tire would cause more fatigue damage, approximately the same rutting damage and less surface-initiated top-down cracking than the conventional dual-tire assembly. On the other hand, the conventional 385/65R22.5 wide-base tire, which was introduced more than two decades ago, caused the most damage.

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