Entrapped Gas and Vapor Formation Influence on Surge Pressure in Liquid Pipeline Systems

2016 ◽  
Author(s):  
David Cheng ◽  
Borith Seng
Keyword(s):  
Experimental Data ◽  
Single Phase ◽  
Air Bubble ◽  
Modeling Methods ◽  
Column Separation ◽  
Design Engineers ◽  
Pipeline Systems ◽  
Entrapped Air ◽  
Pipeline Design ◽  
Vapor Formation

Predicting the effects of entrapped gas or vapor formation on surge is very important in design and operation of liquid pipelines. This paper identified the scenarios in which entrapped air and vapor formation need to be considered in pipeline operation and design. Useful modeling methods utilizing common liquid pipeline transient hydraulics software are provided. Validation of the presented methods was completed using experimental data from published literature. Examples are presented in showing the implementation of the provided modeling methods on real pipeline design scenarios. Finally, advantages and limitations of the presented methods was discussed. The methods presented in this paper enable pipeline operators and design engineers to properly estimate the complicated surge issues such as the influence of air bubble venting and column separation and collapse using commonly available single phase hydraulics tools. The operators and engineers will benefit from the provided methods in finding and validating reliable surge mitigation solutions and creating pipeline design with higher integrity level. The paper also presents the limitation of the methods and continuous improvements that can be achieved in the future.

VIV Predictions for an SCR in Sheared Ocean Currents

2002 ◽  
Author(s):  
Christopher J. Wajnikonis
Keyword(s):  
Experimental Data ◽  
Design Parameters ◽  
Finite Element Analyses ◽  
Steel Catenary Riser ◽  
Specialized Software ◽  
Design Engineers ◽  
Sensitivity Studies ◽  
Deepwater Riser ◽  
Extended Program ◽  
Areas Of Interest

Vortex Induced Vibration (VIV) prediction is one of the key areas of interest in Deepwater Riser Engineering. Several Joint Industry Projects (JIPs) are currently in progress in this field, which results in an increase of experimental data available to design engineers, in revisions of specialized software and in development of new engineering tools. This paper presents VIV predictions for a hypothetical Steel Catenary Riser (SCR) using the latest versions of the SHEAR7 and the VIVA/VIVARRAY Programs. Both built-in and extended program capabilities are utilized and detailed plots of computation results are presented. Sensitivity studies on the influence of variations of selected design parameters are also included in the paper. Finite Element Analyses (FEAs) results and simple engineering tools were utilized in parallel to built-in program features. The calculations demonstrated, that for the riser investigated and presumably also for a wide variety of similar SCRs, that the built in program features are sufficient to predict VIVs conservatively. Notes on VIV predictions in a real ocean and on selected areas that require investigation are also included.

scholarly journals ANALYSIS OF THE CURRENT STATE OF RESEARCHES OF THE DEPOSITION OF ASPHALT-RESINOUS SUBSTANCES, PARAFFIN, AND MODELING METHODS. REVIEW PART II: WAX DEPOSITION

2021 ◽  
pp. 13-23
Author(s):  
M.R. Manafov ◽  
◽  
G.S. Aliyev ◽  
A.I. Rustamova ◽  
V.I. Kerimli ◽  
...  
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Deposition Process ◽  
Real Field ◽  
Wax Deposition ◽  
Scaling Effect ◽  
Modeling Methods ◽  
Current State ◽  
Simulation Results ◽  
Reliable Interpretation

The mechanism of paraffin formation in transport pipes is briefly discussed. A kinetic model of the formation and wax deposition from oil is proposed. Comparison of the model with the available experimental data gave satisfactory results. The review considers software tools for modeling the wax deposition process. It is noted that the simulation results are not always applicable to real field cases. For a more reliable interpretation, the scaling effect must be taken into account. In the work various technologies for wax removal are considered

FEA Tire Modeling and Validation Techniques

2015 ◽  
Author(s):  
Mehrsa Marjani ◽  
Moustafa El-Gindy ◽  
David Philipps ◽  
Fredrik Öijer ◽  
Inge Johansson
Keyword(s):  
Experimental Data ◽  
Dynamic Characteristics ◽  
Rolling Resistance ◽  
Vertical Acceleration ◽  
Virtual Model ◽  
Static And Dynamic Characteristics ◽  
Modeling Methods ◽  
Truck Tire ◽  
Tire Modeling ◽  
Tire Models

Recent advances in power and efficiency of computerized modeling methods has made it easier to develop accurate tire models. These newer models are now created with such accuracy that it has become easy to predict the experimental tire’s behavior and characteristics. These models are helpful with determining tire, tire-road, and tire-soil interaction properties. By creating virtual models, the overall capital for research and development can be reduced as well as replacing unavailable experimental tires for research. This research paper mainly focuses on the validation of computer generated FEA tire models which are then used for the prediction of the experimental tire’s rolling resistance, static and dynamic characteristics. Experimental data, such as rolling resistance and vertical acceleration are used in validation simulations in order to tune the virtual model to match the experimental tire’s behavior. The tire that was used for this research is a six-groove 445/50R22.5 FEA truck tire, which was constructed and validated over the course of this research.

Two-Phase Flow Behavior in Channels With Sudden Area Change Using Experimental and Computational Approach

2017 ◽  
Author(s):  
Ashish Kotwal ◽  
Che-Hao Yang ◽  
Clement Tang
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Experimental Analysis ◽  
Single Phase ◽  
Computational Analysis ◽  
Phase Flow ◽  
Single Phase Flow ◽  
Two Phase ◽  
Flow Rates ◽  
Area Change

The current study shows computational and experimental analysis of multiphase flows (gas-liquid two-phase flow) in channels with sudden area change. Four test sections used for sudden contraction and expansion of area in experiments and computational analysis. These are 0.5–0.375, 0.5–0.315, 0.5–0.19, 0.5–0.14, inversely true for expansion channels. Liquid Flow rates ranging from 0.005 kg/s to 0.03 kg/s employed, while gas flow rates ranging from 0.00049 kg/s to 0.029 kg/s implemented. First, single-phase flow consists of only water, and second two-phase Nitrogen-Water mixture flow analyzed experimentally and computationally. For Single-phase flow, two mathematical models used for comparison: the two transport equations k-epsilon turbulence model (K-Epsilon), and the five transport equations Reynolds stress turbulence interaction model (RSM). A Eulerian-Eulerian multiphase approach and the RSM mathematical model developed for two-phase gas-liquid flows based on current experimental data. As area changes, the pressure drop observed, which is directly proportional to the Reynolds number. The computational analysis can show precise prediction and a good agreement with experimental data when area ratio and pressure differences are smaller for laminar and turbulent flows in circular geometries. During two-phase flows, the pressure drop generated shows reasonable dependence on void fraction parameter, regardless of numerical analysis and experimental analysis.

Statistical Analysis Method of the Grain Structure of Nanostructured Single Phase Metal Materials Processed by High-Pressure Torsion

2018 ◽  
Vol 284 ◽  
pp. 425-430 ◽  
Author(s):  
Alexey V. Stolbovsky ◽  
Elena Farafontova
Keyword(s):  
Experimental Data ◽  
High Pressure ◽  
Statistical Analysis ◽  
Single Phase ◽  
High Pressure Torsion ◽  
Grain Structure ◽  
Analysis Method ◽  
Tin Bronze ◽  
Statistical Analysis Method ◽  
Metal Materials

The statistical analysis method of the grain structure in bulk single-phase metal materials subjected to high-pressure torsion is proposed. The possibility of methods division of mathematical statistics observed in the grain structure materials by their sizes with the several groups identification, having various behavior at further heating is presented. The example of the grain structure analysis on the nanostructured tin bronze is given. The agreement of the received analysis results with experimental data is offered.

Dynamic Modeling of Capsule Separator for Control of Hydraulic Capsule Pipelines

1999 ◽  
Vol 121 (2) ◽  
pp. 233-241 ◽  
Author(s):  
Hongliu Du ◽  
Satish S. Nair
Keyword(s):  
Dynamic Modeling ◽  
Control Strategies ◽  
Hydraulic Design ◽  
Pipeline Systems ◽  
Automation And Control ◽  
Computer Controlled ◽  
Strategy Design ◽  
And Control ◽  
Pipeline Design ◽  
Pipeline Model

Hydraulic capsule pipelines concepts are novel as compared to existing commercial pipeline systems. The complexity of such novel systems places greater demands on sensing, automation, and control strategy design for such systems as compared to existing commercial pipeline systems. These issues, as well as hydraulic design automation and control strategies, are reported. A novel capsule separator design has also been proposed to ensure reliable functioning of ‘booster’ stations for such pipelines. Detailed dynamic modeling of the proposed capsule separator is performed for generating design and control guidelines. Validation of the overall hydraulic capsule pipeline design and control, and limited validation of the proposed capsule separator subsystem, are provided using a prototype hardware computer controlled pipeline model.

Simulation of Air Entrapment by a Plunging Liquid Jet of Finite Length

Volume 1 ◽  
2004 ◽  
Author(s):  
Paul S. Krueger ◽  
Razvan Bidoae ◽  
Peter E. Raad
Keyword(s):  
Finite Length ◽  
Liquid Jet ◽  
Air Entrapment ◽  
Air Bubble ◽  
Pool Surface ◽  
Air Volume ◽  
Large Pool ◽  
Vorticity Generation ◽  
Simulation Results ◽  
Entrapped Air

The impingement of a finite length round water jet on a large pool of water was simulated numerically using a 3D Eulerian-Lagrangian Marker and Micro-Cell (ELMMC) method. The method allowed simulation of the initial impact of the jet on the pool surface, the deformation of the pool surface by the falling jet, and, under certain conditions, the entrapment of an air bubble as the pool closes in on the jet. The conditions considered were for ratios of jet length to radius (h/r) in the range of 4 to 25 and jet Froude number in the range of 16 to 74. The results agreed with previous experimental observations by Oguz et al. (J. Fluid Mech., 294, 1995) in terms of entrapped air volume and the possible geometries of entrapped bubbles (viz., toroidal or spheroidal). The simulation results also allowed for a detailed study of effects difficult to discern experimentally, such as vorticity generation and differences in entrapped air volume between toroidal and spheroidal bubbles.

Numerical Investigation of Heat Transfer Characteristics of Different Nanoparticles Using Modified Eulerian-Eulerian Model

2020 ◽  
Author(s):  
Muzafar Hussain ◽  
Shahbaz Tahir
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Heat Exchangers ◽  
Single Phase ◽  
Reynolds Numbers ◽  
Operating Conditions ◽  
Phase Model ◽  
Heat Transfer Characteristics ◽  
Eulerian Model ◽  
Transfer Characteristics

Abstract Nanofluids are widely adopted nowadays to enhance the heat transfer characteristics in the solar applications because of their excellent thermophysical properties. In this paper, a modified Eulerian-Eulerian model recently developed based on experiments was validated numerically to account for the deviations from the experimental data. The modified Eulerian-Eulerian model is compared with the single-phase model, Eulerian-Eulerian models for TiO2-water at different operating conditions and deviation from the experimental data for each of the model was documented. However, the modified Eulerian-Eulerian model gave much closer results when compared to the experimental data. For the further extension of work, the modified Eulerian-Eulerian model was applied to different nanofluids in order to investigate their heat transfer characteristics. Three different nanoparticles were investigated namely Cu, MgO, and Ag and their heat transfer characteristics is calculated based on the modified Eulerian-Eulerian model as well as the single-phase model for the comparison. For lower values of Reynolds numbers, the average heat transfer coefficient was almost identical for both models with small percentage of error but for higher Reynolds numbers, the deviation got larger. Therefore, single-phase model is not appropriate for higher Reynolds numbers and modified Eulerian-Eulerian model should be used to accurately predict the heat transfer characteristics of the nanofluids at higher Reynolds numbers. From the analysis it is found that the Ag-water nanofluid have the highest heat transfer characteristics among others and can be employed in the solar heat exchangers to enhance the heat transfer characteristics and to further improve the efficiency.

Frictional Pressure Losses for Annular Flow of Drilling Mud and Mud-Gas Mixtures

1985 ◽  
Vol 107 (1) ◽  
pp. 142-151 ◽  
Author(s):  
J. P. Langlinais ◽  
A. T. Bourgoyne ◽  
W. R. Holden
Keyword(s):  
Experimental Data ◽  
Single Phase ◽  
Two Phase Flow ◽  
Hydraulic Diameter ◽  
Phase Flow ◽  
Drilling Mud ◽  
Two Phase ◽  
Bingham Plastic ◽  
Pressure Losses ◽  
Annular Geometry

The calculation of single-phase and two-phase flowing pressure gradients in a well annulus is generally based on an extension of empirical correlations developed for Newtonian fluids in circular pipes. Various techniques for extending pipe flow correlations to an annular geometry have been presented in the literature which involve the representation of the annular well geometry with an equivalent circular diameter and the representation of non-Newtonian fluid behavior with an apparent Newtonian viscosity. Unfortunately, little experimental data have been available which would allow a comparison of the relative accuracy of the various proposed techniques. In this study, experimental pressure gradient data have been taken in two 6000-ft wells. Frictional pressure losses for single-phase flow (mud only) in two annuli were compared to values predicted by the Bingham plastic and power law models. These calculations utilized the equivalent diameters defined by the Crittendon criteria, the hydraulic diameter, and the slot approximation. Also, total pressure difference for two-phase flow was measured for one annular geometry. This data was compared to that predicted by the Poettmann and Carpenter, Hagedorn and Brown, Orkiszewski, and Beggs and Brill correlations. Comparison of experimental data with the various prediction techniques was favorable, each having advantage in certain situations. For the data investigated, the Crittendon criteria using a Bingham plastic model gave the best results. The two-phase flow data was best predicted by the Hagedorn and Brown correlation utilizing an equivalent hydraulic diameter.

Sign in / Sign up

Export Citation Format

Share Document