scholarly journals Analysis on the escape phenomenon of oil mist from turbine lower guide bearing based on VOF model

2021 ◽  
Vol 13 (11) ◽  
pp. 168781402110609
Author(s):  
Jiayang Pang ◽  
Huizi Liu ◽  
Xiaobing Liu ◽  
Minghui Ren ◽  
Pan Zhang ◽  
...  
Keyword(s):  
Flow Field ◽  
Labyrinth Seal ◽  
Economic Benefits ◽  
Lubricating Oil ◽  
Escape Phenomenon ◽  
Vof Model ◽  
Oil Mist ◽  
Oil Tank ◽  
Oil Gas ◽  
Bearing Structure

To analyze the cause and mechanism of oil mist escaping from the lower guide bearing during the operation of a turbine, the oil-gas mixture in the lower guide bearing was numerically simulated by using the VOF two-phase flow model and the SST turbulence model. The influences of different sealing clearances and speeds on the flow field and the oil-gas distribution in the oil tank were studied, and the escaping characteristics of oil mist were analyzed. The results show that increasing the clearance of the labyrinth seal will reduce the pressure difference between the inside and outside of the oil tank and reduce the driving force for the escape of the oil mist. However, increasing the clearance will increase the turbulence of the flow field, the number and volume of bubbles in the lubricating oil, which will lead to the uneven distribution of oil and gas and reduce the motion stability of the lower guide bearing. The change of speed will affect the normal use of the shaft-collar pump. High speed will aggravate the generation of bubbles in the oil tank and increase the possibility of cavitation in the lower guide bearing structure. In engineering practices, it is necessary to comprehensively consider factors such as oil mist escape phenomenon, economic benefits, process manufacturing and assembly, and adopt the lower guide bearing structure with a suitable labyrinth seal clearance.

Effects of Perforated Flow Tube on the Flow Field of a Blowout Well

SPE Journal ◽  
2016 ◽  
Vol 21 (04) ◽  
pp. 1470-1476 ◽  
Author(s):  
Ebrahim Hajidavalloo ◽  
Saeed Alidadi Dehkohneh
Keyword(s):  
Flow Field ◽  
Flow Tube ◽  
Gas Well ◽  
Safety Measures ◽  
Team Members ◽  
Well Control ◽  
Blowout Preventer ◽  
New Type ◽  
Oil Gas ◽  
Simple Flow

Summary When a blowout oil/gas well catches fire, usually a flow tube is used to detach the fire from the wellhead and provide appropriate conditions for operating team members to approach the well and install the blowout-preventer (BOP) cap. Using the flow tube above the wellhead creates powerful suction around the tube that may jeopardize the safety of crew members. To reduce the power of suction around the well, a new perforated flow tube instead of simple flow tube was introduced. To understand the effect of this new type of flow tube, modeling and simulation of the flow field around the blowout well were performed for both simple and perforated types of flow tube with Fluent 6.3.26 (2003) and Gambit 2.3.16 (2003) softwares. Different parameters around the well mouth were compared in both designs. The results showed that using the perforated flow tube decreases the vacuum around the well by 33% compared with the simple flow tubes. Thus, application of the perforated flow tube can be recommended in well-control operations for safety measures.

Influence of a Honeycomb Facing on the Flow Through a Stepped Labyrinth Seal

2000 ◽  
Vol 124 (1) ◽  
pp. 140-146 ◽  
Author(s):  
V. Schramm ◽  
K. Willenborg ◽  
S. Kim ◽  
S. Wittig
Keyword(s):  
Flow Field ◽  
Three Dimensional ◽  
Theoretical Work ◽  
Labyrinth Seal ◽  
Honeycomb Structure ◽  
Experimental Investigations ◽  
Labyrinth Seals ◽  
Numerical Predictions ◽  
Flow Through ◽  
Aero Engines

This paper reports numerical predictions and measurements of the flow field in a stepped labyrinth seal. The theoretical work and the experimental investigations were successfully combined to gain a comprehensive understanding of the flow patterns existing in such elements. In order to identify the influence of the honeycomb structure, a smooth stator as well as a seal configuration with a honeycomb facing mounted on the stator wall were investigated. The seal geometry is representative of typical three-step labyrinth seals of modern aero engines. The flow field was predicted using a commercial finite volume code with the standard k-ε turbulence model. The computational grid includes the basic seal geometry as well as the three-dimensional honeycomb structures.

A Measure to Imitate the Boundary Condition of Local Structure in Modal Analysis

2012 ◽  
Vol 594-597 ◽  
pp. 896-899
Author(s):  
Yu Chao Song ◽  
Biao Yang ◽  
Hong Liang Yu
Keyword(s):  
Boundary Condition ◽  
Modal Analysis ◽  
Local Structure ◽  
Lubricating Oil ◽  
Deformation Analysis ◽  
Beam Model ◽  
Coupling Vibration ◽  
Oil Tank ◽  
The Difference ◽  
Main Engine

The static element in static deformation analysis was used to simulate the boundary condition of local structure when studying the modality of local structure. Using this method, the vibration modality of a beam system and the main engine lubricating oil tank were researched. The results show that the usage of static element in dynamic analysis can solve the vibration modality of local structure accurately, the difference ratio of first order frequency is less than 1/10000 in the beam model analysis, and the modal analysis of main engine lubrication oil tank has a good performance, which is a helpful base for the coupling vibration research in ship structure.

Study of Flow Characteristics of Oil and Water in the Process of Stirring

2013 ◽  
Vol 353-356 ◽  
pp. 3190-3193
Author(s):  
Zong Rui Hao ◽  
Juan Xu ◽  
Hai Yan Bie ◽  
Zhong Hai Zhou
Keyword(s):  
Flow Field ◽  
Flow Pattern ◽  
Cross Section ◽  
Radial Flow ◽  
Flow Characteristics ◽  
Stirred Tank ◽  
Turbulent Model ◽  
Vof Model ◽  
Circular Flows ◽  
Oil Water

To study the flow pattern in the process of oil-water stirring in three paddle stirring tank, RNG k-ε turbulent model and VOF model are adopted to simulate the flow field at different time in the stirred tank with the baffle. The results showed that, in the stirring process, inverted cone manifold was formed in the center of the stirring shaft. The stratified area was formed in the baffle and gradually transported to the bottom of the tank. The two circular flows were formed among three groups of blades. And the axially acting of the fluid was strong, which made homogeneous stirring in the stirred tank. At the same time the radial flow of the cross-section inside the tank increased because of the baffle.

Unsteady Interaction of Labyrinth Seal Leakage Flow and Downstream Stator Flow in a Shrouded 1.5 Stage Axial Turbine

2005 ◽  
Author(s):  
P. Peters ◽  
J. R. Menter ◽  
H. Pfost ◽  
A. Giboni ◽  
K. Wolter
Keyword(s):  
Flow Field ◽  
Three Dimensional ◽  
Numerical Data ◽  
Labyrinth Seal ◽  
Rotor Blades ◽  
Navier Stokes ◽  
Experimental Program ◽  
Leakage Flow ◽  
Axial Turbine ◽  
Flow Phenomena

This paper presents the results of experimental and numerical investigations into the flow in a 1.5-stage low-speed axial turbine with shrouded rotor blades and a straight through labyrinth seal. The paper focuses on the time dependent influence of the leakage flow on the downstream stator flow field. The experimental program consists of time accurate measurements of the three-dimensional properties of the flow through ten different measurement planes in the stator passage. The measurements were carried out using pneumatic five-hole probes and three dimensional hot-wire probes at the design operating point of the turbine. The measurement planes extend from the shroud to the casing. The complex three-dimensional flow field is mapped in great detail by 4,800 measurement points and 20 time steps per blade passing period. The time-accurate experimental data of the ten measurement planes was compared with the results of unsteady, numerical simulations of the turbine flow. The 3D-Navier-Stokes Solver CFX-TASCflow was used. The experimental and numerical results correspond well and allow detailed analysis of the flow phenomena. Additionally numerical data behind the rotor is used to connect the entry of the leakage flow with the flow phenomena in the downstream stator passage and behind it. The leakage flow causes strong fluctuations of the flow in the downstream stator. Above all, the high number of measurement points reveals both the secondary flow phenomena and the vortex structures within the blade passage. The time-dependence of both the position and the intensity of the vortices influenced by the leakage flow is shown. The paper shows that even at realistic clearance heights the leakage flow influences considerable parts of the downstream stator and gives rise to negative incidence and flow separation. Thus, labyrinth seal leakage flow should be taken properly into account in the design or optimization process of turbines.

Numerical Simulation on Hydraulic Characteristics of Underflow for Falling-Sill Bottom-Flow Dissipation

2013 ◽  
Vol 864-867 ◽  
pp. 2027-2030
Author(s):  
Shan Shan Lu ◽  
Hua Li ◽  
Hui Chao Dai ◽  
Quan Lin Ding
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Scientific Basis ◽  
Flow Speed ◽  
Turbulent Motion ◽  
Hydraulic Characteristics ◽  
Two Phase ◽  
Plunge Pool ◽  
Vof Model ◽  
Flow Vortex

Falling-sill bottom-flow dissipation is an important energy dissipater way, which has two fluent characteristics, spatial 3D hydraulic jump and submerge jet. But the turbulent motion is strong with a flow pattern of complex level. It is hard to detail the hydraulic characteristics and strength being inside of the plunge pool using physical experiments. However, numerical simulation can match the deficiency of physical model, which has the access to detail flow field hydraulic characteristics and provide a strong scientific basis on analyzing the hydrodynamic and hydraulic characteristics of plunge pool. In this paper, XJB project is taken for example, gas-liquid two-phase flow tracking the simulation free surface of VOF model was used. The RNG κ_ε turbulent motion model is adequate to simulate the 3D flow field in plunge pool. The result shows that the consequence of numerical simulation and physic test match well, which can reflect the plunge pool hydraulic characteristics and dissipation process accurately. The distribution of flow speed inside the plunge pool locates the position of main flow and reflects the velocity decay along the way and reflux flow vortex .

A Numerical Simulations and Optimizations of the Flow Field in TengZhou Quanshang Constructed Wetland

2012 ◽  
Vol 212-213 ◽  
pp. 201-204
Author(s):  
Wei Gang Xu ◽  
Hua Yong Zhang ◽  
Zhong Yu Wang ◽  
Wen Pei Huang
Keyword(s):  
Flow Field ◽  
Constructed Wetland ◽  
Large Scale ◽  
Flow Analysis ◽  
Initial State ◽  
Measured Velocity ◽  
Efficient Operation ◽  
Water Quality Simulation ◽  
Vof Model ◽  
Large Scale Flow

The flow field of constructed wetland plays an important role in wetland stabilization and efficient operation. TengZhou Quanshang constructed wetland was taken as the research object. The RNG k-ε two-equation turbulence model equations coupling with the volume of fluid (VOF) model are introduced to simulation the vegetation cover flow. And the flow velocities of 37 measured points in wetland were measured by using the ADV instrument. Then the simulation velocity was compared with the field measured velocity. The results are shown to be satisfactory, and basically meet the large-scale flow analysis requirements. The problems of flow field distribution on the initial state was analyzed and optimized. The uniformity of velocity in wetland increased, and water mobility improved after optimization. Our results provide guidance for the 2D water quality simulation, pollutants migration and combination of plant purification effect in natural and constructed wetland.

Research on a Scheme of Real-Time Measuring of Lubrication Oil Quantity in an Aero-Engine Tank

2011 ◽  
Vol 317-319 ◽  
pp. 2079-2084
Author(s):  
Rang Shu Xu ◽  
Xiao Wen Chen ◽  
Jian Ming Yang ◽  
Zhi Wei Dong ◽  
Min Li Bai
Keyword(s):  
Interpolation Method ◽  
Oil Quality ◽  
Phase Interface ◽  
Measuring System ◽  
Dead Volume ◽  
Lubricating Oil ◽  
Digital Measurement ◽  
Vof Model ◽  
Data Tables ◽  
Height Data

The composition and principles of the digital measuring system was investigated on the basis of digital oil measuring method. Fly attitude-oil quality - measuring height data tables were generated by using UG software calculation of oil quantity characteristics. Then the oil surface angle under different fly attitude and overload was calculated through coordinate transformation method. Finally the amount of oil was calculated by three-dimensional liner interpolation method. Meanwhile, the free surface movement of lubricating oil tank under different overload was simulated through VOF numerical model. The results showed that using UG software to build model and generate fly attitude-oil quantity-measuring height data tables is accurate and useful. The VOF model method is a complement to digital measurement, which can track the phase interface of continuum, analyze the movement of oil qualitatively and calculate the dead volume of digital method.

scholarly journals Kajian Kegagalan Komponen Dan Perawatan Pada Sistem Pelumas Mesin Diesel Di Kapal

2021 ◽  
pp. 1-6
Author(s):  
Ratna Indriyani ◽  
Dwisetiono Dwisetiono
Keyword(s):  
Failure Mode ◽  
Preventive Maintenance ◽  
Lubricating Oil ◽  
Effect Analysis ◽  
Corrective Maintenance ◽  
Oil Pump ◽  
Oil Cooler ◽  
Oil Tank ◽  
Main Engine

Mesin diesel sebagai mesin induk di kapal dapat berfungsi dengan baik apabila ditunjang oleh sistem-sistem pendukung yang baik seperti sistem pelumas (lubricating oil system). Sistem pelumas salah satu sistem yang sangat penting dalam pengoperasian kapal, kegagalan pada sistem pelumasan menyebabkan sistem tidak beroperasi semestinya dan dapat mengalami kerugian dari pihak kapal. Kajian ini bertujuan untuk mengetahui kagagalan pada setiap komponen sistem pelumas di main engine dan perawatan yang tepat. Kajian ini dilakukan dengan menggunakan metode Failure Mode and Effect Analysis (FMEA) untuk mengoptimalkan cara mengatasi kegagalan dan perawatan mesin utama kapal untuk mengidentifikasi strategi dan prioritas perawatan. Dengan menggunakan FMEA dapat mengetahui kegagalan serta efek yang ditimbulkan oleh tiap-tiap komponen dapat diketahui dan untuk melakukan perawatan harus mengelompokan komponen berdasarkan tingkat resiko rendah sampai tinggi. Komponen lubricating oil tank dan sump tank memiliki resiko yang rendah, lubricating oil cooler memiliki resiko sedang dan lubricating oil pump, lubricating oil filter, purifier, transfer pump dan lubricating purifier heater memiliki resiko tinggi. Hasil dari kegagalan komponen sistem pelumas sangat berguna untuk mengidentifikasi strategi perawatan berdasarkan tingkat resiko komponen tersebut dengan memilih antara perawatan pencegahan (preventive maintenance) dan perawatan korektif (corrective maintenance).

Study on Thermal Insulation Solutions for Submarine Oil Storage in Offshore Gravity Platform

2014 ◽  
Vol 998-999 ◽  
pp. 1470-1473 ◽  
Author(s):  
Wen Juan Li ◽  
Yin Bang Wang ◽  
Wen Hui Wu
Keyword(s):  
Energy Consumption ◽  
Economic Benefits ◽  
Contrastive Analysis ◽  
Storage Technology ◽  
Oil Storage ◽  
Oil Tank ◽  
Reduce Energy Consumption ◽  
Gravity Platform ◽  
Heat Preservation ◽  
Offshore Oil

As application of gravity platform is increasing rapidly in marginal oilfields, the heat preservation performance of the submarine oil tank is becoming more and more important in offshore oil storage technology. In order to enhance heat preservation performance of the concrete oil tank to reduce energy consumption, three insulation solutions were proposed in this paper. Contrastive analysis shows that polyurethane solution can not only maximize economic benefits but also possess high engineering feasibility and environmental value.

Sign in / Sign up

Export Citation Format

Share Document