Three-Dimensional CFD Simulation for Water-Lubricated Guide Bearing of Large Tubular Pump

A numerical simulation for flow field in water-lubricated guide bearing of large tubular pump is conducted by software Fluent, which shows the pressure distribution of water film with different rotating speeds and the rule of the influence of relevant parameters on the amount of lubricating water, dynamic and static characteristics of guide bearing.The result shows that the pressure distributions of water film at low and high speeds are very different, and with the obvious dynamic pressure effect, the bearing inner can be in a state of reflux and the water-lubricated amount and clearance are reduced. The load capacity and stiffness of guide bearing are increased along with the speed and water pressure increase meanwhile the amount of water is increased along with the speed lowering and the water pressure and clearance increase.

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THE EFFECT OF HELICAL GROOVE PRESENCE ON THE TRIBOLOGICAL PERFORMANCE OF JOURNAL BEARINGS

Tribologia ◽

10.5604/01.3001.0012.7021 ◽

2018 ◽

Vol 279 (3) ◽

pp. 131-138

Author(s):

Jarosław SĘP ◽

Leszek TOMCZEWSKI ◽

Lidia GAŁDA

Keyword(s):

Load Capacity ◽

Three Dimensional ◽

Flow Simulation ◽

Equation System ◽

Journal Bearings ◽

Operating Conditions ◽

Static Characteristics ◽

Hydrodynamic Bearings ◽

Oil Flow ◽

Helical Groove

The hydrodynamic bearings could suffer critical damages operating in contaminated environments that cause machine breakdown. In such hard operating conditions, hydrodynamic bearings with grooved journals are less sensitive to damage compared to plain bearings. The wear resistance of the grooved journal bearings is several times greater than that of smooth journal bearings. Contaminants existing in the oil film are moved out from the bearing clearance by the groove created on the journal surface. The presence, shape, and geometry of the groove strongly influence the bearings performance. The aim of this article is to study the selected static characteristics of bearings consisting of a journal with the helical groove on its surface. The static characteristics were determined based on the flow simulation in the oil clearance. A three-dimensional, adiabatic model of the oil flow was assumed. The oil flow was described with the Navier-Stokes continuity and energy equations. The equation system was solved by the finite volume method. The numerical model of the flow was verified experimentally on a test stand. It has been established that the grooved journal application leads to a decrease of load capacity in whole range of eccentricity and for all examined clearances. The oil flow rate increase was mainly observed due to spiral groove presence on the shaft.

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An Evaluation of Simulated Flow and Experimental Study Through an Axial Fan

Volume 1: 23rd Computers and Information in Engineering Conference, Parts A and B ◽

10.1115/detc2003/cie-48252 ◽

2003 ◽

Author(s):

J. Xie ◽

R. S. Amano ◽

E. K. Lee

Keyword(s):

Experimental Study ◽

Cfd Simulation ◽

Dynamic Pressure ◽

Experimental Studies ◽

Three Dimensional ◽

Axial Fan ◽

Rotating Reference Frame ◽

Speed Up ◽

Fan Blade ◽

Simulated Flow

A comprehensive three-dimensional CFD approach and experimental study is developed for a 6-ft diameter commercial axial fan with rotational speed up to 1014 rpm. The use of sophisticated CFD software has made it possible to simulate fluid flow in complex moving geometries found in rotating machinery such as fans, pumps compressors, etc. In this paper, FLUENT is used to study an axial fan performance. Simulations are performed for steady state conditions using an implicitly rotating reference frame for the blades. Experimental studies are also conducted to visualize the flow on fan blade surface by using tuft method. The pressure and velocity distribution in front of the fan and the uncertainty dynamic pressure field measurement are also carried out. Comparisons between CFD simulation results and experimental measurement are found to be reasonable.

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An Experimental Study on Externally Pressurized Supersonic Gas Thrust Bearings

Journal of Tribology ◽

10.1115/1.3260987 ◽

1985 ◽

Vol 107 (1) ◽

pp. 122-127 ◽

Cited By ~ 1

Author(s):

Yutaka Miyake ◽

Takehiko Inaba ◽

Naoshige Kubo ◽

Jun-ichi Takeoka

Keyword(s):

Experimental Study ◽

Flow Rate ◽

Load Capacity ◽

Experimental Results ◽

Static Characteristics ◽

Thrust Bearings ◽

Pressure Distributions ◽

Theoretical Predictions ◽

New Type ◽

Good Agreement

Externally pressurized supersonic gas thrust bearings whose generation of load capacity is substantially independent of the viscosity of working fluids, have been proposed and analyzed by the authors. This report presents the experimental results of the static characteristics of this new type of bearings. The experimental results including load capacity, stiffness, mass flow rate, and pressure distributions in the bearing clearance, generally show a good agreement with the theoretical predictions and verify the validity of this new bearing. The effect of an orifice to improve the stiffness is also examined. Some problems which should be solved to put the bearing in practical use are pointed out.

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CFD Research on Aerostatic Bearing with Tangential Supply Holes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.2021 ◽

2010 ◽

Vol 97-101 ◽

pp. 2021-2026 ◽

Cited By ~ 1

Author(s):

He Chun Yu ◽

Wen Qi Ma ◽

Zu Wen Wang ◽

Li Fang Xu

Keyword(s):

Load Capacity ◽

Dynamic Effect ◽

Three Dimension ◽

Static Characteristics ◽

Pressure Distributions ◽

Theoretical Support ◽

Gas Consumption ◽

Aerostatic Bearings ◽

Volume Method ◽

Gas Supply

The radial aerostatic bearings with reversely tangential gas supply holes have been proved successfully in some applications to improve the dynamic stability. However, the concept lacks firm theoretical support. Aerostatic bearings with reversely tangential gas supply holes and radial gas supply holes were designed. The finite volume method (FVM) was used to solve the three-dimension flow field, the static characteristics of them were studied, and the following conclusions were drawn: The tangential gas supply holes can improve the pressure distributions in the working clearance, but they can’t effectively improve the load capacity and stiffness. The improvement of the characteristics of aerostatic bearings with tangential gas supply holes is at the expense of excessive gas consumption. For aerostatic bearings, when the eccentricity ( ) is large and the rotor speed ( ) is high, the dynamic effect can effectively improve the load capacity and stiffness.

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The Hydromechanical Interplay in the Simplified Three-Dimensional Limit Equilibrium Analyses of Unsaturated Slope Stability

Geosciences ◽

10.3390/geosciences11020073 ◽

2021 ◽

Vol 11 (2) ◽

pp. 73

Author(s):

Panagiotis Sitarenios ◽

Francesca Casini

Keyword(s):

Analytical Solution ◽

Slope Stability ◽

Slope Failure ◽

Failure Modes ◽

Pore Water Pressure ◽

Limit Equilibrium ◽

Water Pressure ◽

Three Dimensional ◽

Stability Limit ◽

Smooth Transition

This paper presents a three-dimensional slope stability limit equilibrium solution for translational planar failure modes. The proposed solution uses Bishop’s average skeleton stress combined with the Mohr–Coulomb failure criterion to describe soil strength evolution under unsaturated conditions while its formulation ensures a natural and smooth transition from the unsaturated to the saturated regime and vice versa. The proposed analytical solution is evaluated by comparing its predictions with the results of the Ruedlingen slope failure experiment. The comparison suggests that, despite its relative simplicity, the analytical solution can capture the experimentally observed behaviour well and highlights the importance of considering lateral resistance together with a realistic interplay between mechanical parameters (cohesion) and hydraulic (pore water pressure) conditions.

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A New Method to Calculate Water Film Stiffness and Damping for Water Lubricated Bearing with Multiple Axial Grooves

Chinese Journal of Mechanical Engineering ◽

10.1186/s10033-020-00492-w ◽

2020 ◽

Vol 33 (1) ◽

Author(s):

Guojun Ren

Keyword(s):

Analytical Procedure ◽

Load Capacity ◽

Water Film ◽

New Method ◽

Hard Materials ◽

Stiffness And Damping ◽

Film Stiffness ◽

Hydro Turbines

Abstract Water lubricated guide bearings for hydro turbines and pumps are conventionally designed with multiple axial grooves to provide effectively cooling and flushing away abrasives. Due to the variety of groove configuration in terms of number and size, a predication of their performance is difficult. This paper deals with an analytical procedure to investigate groove effect on load capacity, stiffness and damping for this type of bearing where it is considered as an assembly of many inclined slide bearings. The result can be applied to bearings made of hard materials combined with low bearing pressure.

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Study of dynamic pressure on the packer for deep-water perforation

Open Physics ◽

10.1515/phys-2021-0025 ◽

2021 ◽

Vol 19 (1) ◽

pp. 215-223

Author(s):

Hao Huang ◽

Qiao Deng ◽

Hui Zhang

Keyword(s):

Deep Water ◽

Peak Pressure ◽

Orthogonal Design ◽

Dynamic Pressure ◽

Three Dimensional ◽

Calculation Model ◽

Well Testing ◽

Technical Problems ◽

Wellbore Pressure ◽

Three Dimensional Finite Element

Abstract The packer is one of the most important tools in deep-water perforation combined well testing, and its safety directly determines the success of perforation test operations. The study of dynamic perforating pressure on the packer is one of the key technical problems in the production of deep-water wells. However, there are few studies on the safety of packers with shock loads. In this article, the three-dimensional finite element models of downhole perforation have been established, and a series of numerical simulations are carried out by using orthogonal design. The relationship between the perforating peak pressure on the packer with the factors such as perforating charge quantity, wellbore pressure, perforating explosion volume, formation pressure, and elastic modulus is established. Meanwhile, the database is established based on the results of numerical simulation, and the calculation model of peak pressure on the packer during perforating is obtained by considering the reflection and transmission of shock waves on the packer. The results of this study have been applied in the field case of deep-water well, and the safety optimization program for deep-water downhole perforation safety has been put forward. This study provides important theoretical guidance for the safety of the packer during deep-water perforating.

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A Three-Dimensional Numerical and Multi-Objective Optimal Design of Wavy Plate-Fins Heat Exchangers

Processes ◽

10.3390/pr9010009 ◽

2020 ◽

Vol 9 (1) ◽

pp. 9

Author(s):

Chao Yu ◽

Xiangyao Xue ◽

Kui Shi ◽

Mingzhen Shao

Keyword(s):

Heat Exchangers ◽

Cfd Simulation ◽

Three Dimensional ◽

Basis Functions ◽

Approximation Model ◽

Multi Objective Optimization ◽

Multi Objective ◽

Multi Objective Genetic Algorithm ◽

Colburn Factor ◽

Heat Exchange Efficiency

This paper presents a method for optimizing wavy plate-fin heat exchangers accurately and efficiently. It combines CFD simulation, Radical Basis Functions (RBF) with multi-objective optimization to improve the performance. The optimization of the Colburn factor j and the friction coefficient f is regarded as a multi-objective optimization problem, due to the existence of two contradictory goals. The approximation model was obtained by Radical Basis Functions, and the shape of the heat exchanger was optimized by multi-objective genetic algorithm (MOGA). The optimization results showed that j increased by 17.62% and f decreased by 20.76%, indicating that the heat exchange efficiency was significantly enhanced and the fluid structure resistance reduced. Then, from the aspects of field synergy and tubulence energy, the performance advantage of the optimized structure was further confirmed.

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