scholarly journals Research on the Dynamic Responses of Simply Supported Horizontal Pipes Conveying Gas-Liquid Two-Phase Slug Flow

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 83
Author(s):  
Gang Liu ◽  
Zongrui Hao ◽  
Yueshe Wang ◽  
Wanlong Ren
Keyword(s):  
Slug Flow ◽  
Peak Frequency ◽  
Dynamic Responses ◽  
Piping System ◽  
Transverse Displacement ◽  
Vibration Acceleration ◽  
Two Phase ◽  
Horizontal Pipes ◽  
Simply Supported ◽  
Superficial Gas Velocity

The dynamic responses of simply supported horizontal pipes conveying gas-liquid two-phase slug flow are explored. The intermittent characteristics of slug flow parameters are mainly considered to analyze the dynamic model of the piping system. The results show that the variations of the midpoint transverse displacement could vary from periodic-like motion to a kind of motion whose amplitude increases as time goes on if increasing the superficial gas velocity. Meanwhile, the dynamic responses have certain relations with the vibration acceleration. By analyzing the parameters in the power spectrum densities of vibration acceleration such as the number of predominant frequencies and the amplitude of each peak frequency, the dynamic behaviors of the piping system like periodicity could be calculated expediently.

Numerical Simulation of the Transient Development of Slug Flow in Horizontal Pipes

2016 ◽  
Vol 819 ◽  
pp. 300-304 ◽  
Author(s):  
Zahid Ibrahim Al-Hashimy ◽  
Hussain H. Al-Kayiem ◽  
Mohammad Shakir Nasif ◽  
Abdalellah. O. Mohmmed
Keyword(s):  
Flow Regime ◽  
Slug Flow ◽  
Two Phase Flow ◽  
Piping System ◽  
Phase Flow ◽  
Two Phase ◽  
Horizontal Pipe ◽  
Horizontal Pipes ◽  
Flow Phenomena ◽  
Multi Phase Flow

Slug flow regime in two and multi-phase flow in pipes is a complicated flow phenomena representing challenge in the design of the piping system. In the present work, water/air two phase flow was modeled and simulated as 3 dimensional, transient, and incompressible flow using Volume of Fluid technique in STAR-CCM+ software. The simulation was conducted to predict and evaluate the air-water slug flow in a horizontal pipe with 0.16 m diameter and 7 m long. The superficial velocities for both phases were extracted from Baker chart slug zone. The results were validated against experimental bench marking referenced in Baker chart and the proposed VOF technique shows a good capability in simulating the development of the slug flow regime. This model could be utilized for simulation of various two phase flow regimes.

Experimental Determination of Hydrodynamic Parameters of Air-Water Two-Phase Slug Flow in Horizontal Pipes

2012 ◽  
Author(s):  
Carlos H. Romero ◽  
María A. Márquez ◽  
Sissi D. Vergara ◽  
María T. Valecillos
Keyword(s):  
Slug Flow ◽  
High Speed ◽  
Electronic Device ◽  
Water System ◽  
Superficial Velocity ◽  
Two Phase ◽  
Horizontal Pipes ◽  
Type Pattern ◽  
Elongated Bubble

Two phase slug flow is the most common flow pattern for horizontal and near-horizontal pipelines. This study is designed to determine experimental velocities of elongated bubbles, lengths of liquid slugs and elongated bubbles, and slug frequencies for twenty flow rates combinations of a two phase air-water system that belong to a slug type pattern in horizontal pipes with a non invasive electronic device made of Photo-diodes (emitter) and photo-transistors (receiver) in a non visible length wave of 940 nanometers. The non intrusive electronic device is validated by simultaneously taking pictures with a high speed camera, (Kodak model Ektapro 4540 mx Imager, at shooting speed of 4500 frames per second, the picture resolution is 256 × 256 pixels), through a visualization cell filled with glycerin. This work is done with acrylic pipes of 0,03175 m inner diameter, to ensure complete flow development, the pictures are taken from a visualization cell located at a x/D = 249, the electronic device is located at x/D = 250. Air superficial velocity ranged between 0.156 and 0.468 m/s while water superficial velocity ranged between 0.159 and 1.264m/s. It is found that the non intrusive electronic device formed by photo diodes and photo transistors is an accurate technique that can be used in the determination of elongated bubble velocities, lengths and slug frequencies.

scholarly journals Optimization and Extended Applicability of Simplified Slug Flow Model for Liquid-Gas Flow in Horizontal and Near Horizontal Pipes

Energies ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 842
Author(s):  
Tea-Woo Kim ◽  
Nam-Sub Woo ◽  
Sang-Mok Han ◽  
Young-Ju Kim
Keyword(s):  
Slug Flow ◽  
Pressure Loss ◽  
Gas Flow ◽  
Flow Model ◽  
Flow Coefficient ◽  
Coefficient Of Determination ◽  
Liquid Holdup ◽  
Two Phase ◽  
Horizontal Pipes ◽  
Image Velocimetry

The accurate prediction of pressure loss for two-phase slug flow in pipes with a simple and powerful methodology has been desired. The calculation of pressure loss has generally been performed by complicated mechanistic models, most of which require the iteration of many variables. The objective of this study is to optimize the previously proposed simplified slug flow model for horizontal pipes, extending the applicability to turbulent flow conditions, i.e., high mixture Reynolds number and near horizontal pipes. The velocity field previously measured by particle image velocimetry further supports the suggested slug flow model which neglects the pressure loss in the liquid film region. A suitable prediction of slug characteristics such as slug liquid holdup and translational velocity (or flow coefficient) is required to advance the accuracy of calculated pressure loss. Therefore, the proper correlations of slug liquid holdup, flow coefficient, and friction factor are identified and utilized to calculate the pressure gradient for horizontal and near horizontal pipes. The optimized model presents a fair agreement with 2191 existing experimental data (0.001 ≤ μL ≤ 0.995 Pa∙s, 7 ≤ ReM ≤ 227,007 and −9 ≤ θ ≤ 9), showing −3% and 0.991 as values of the average relative error and the coefficient of determination, respectively.

Non-Invasive Method for Velocity and Slug Length Measurements in Gas/Liquid Flow in Horizontal Pipes

2005 ◽  
Author(s):  
S. Al-Lababidi ◽  
M. L. Sanderson
Keyword(s):  
Liquid Flow ◽  
Liquid Velocity ◽  
Correlation Technique ◽  
Translational Velocity ◽  
Two Phase ◽  
Horizontal Pipe ◽  
Horizontal Pipes ◽  
Non Invasive ◽  
Gas Liquid Flow ◽  
Superficial Gas Velocity

A method was developed for the measurement of slug frequency, slug velocity and slug length of two-phase gas/liquid flow under slug conditions in 2-inch horizontal pipe. The method consists of two pairs of ultrasonic transducers with 1MHz frequency. Non-invasive detection for slugs was achieved over a range of (0.1–1 ms−1) superficial liquid velocity and (0.1–3 ms−1) superficial gas velocity. The slug translational velocity was measured using a cross correlation technique for the modulated ultrasonic signals received. The slug length was measured after measuring the slug time t(slug) and slug translational velocity. The slug parameters measured were extensively compared with conductivity probes measurements and experimental correlations.

Computational Estimation of Bubble Gas Velocity for Slug Flow Pattern in Horizontal Pipes Using Image Processing Technique

2012 ◽  
Author(s):  
María T. Valecillos ◽  
Carlos H. Romero ◽  
María A. Márquez ◽  
Sissi D. Vergara
Keyword(s):  
Image Processing ◽  
Flow Pattern ◽  
Slug Flow ◽  
High Speed ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Gas Velocity ◽  
Two Phase ◽  
Horizontal Pipes ◽  
Computational Estimation

Two-phase slug flow pattern is one of the most common flow patterns present in many industries, therefore its study becomes relevant. The aim of this work was to develop an automated computational program to determine the bubble gas velocity associated to gas-liquid two-phase slug flow by using video digital image processing technique. In order to obtain the images for the analysis, experiments were carried out using a pipe bench for air-water two-phase flow. The experimental facility is located in Simon Bolivar University, in Venezuela. The system has three pipes with different internal diameters and can be rotated around its axis and fixed at any inclination angle from horizontal to vertical flow. The tests were run in a horizontal pipeline of 0.03175m of internal pipe diameter and 8m long. For slug flow visualization a high speed camera Kodak Ektapro 4540mx imager was used. The camera was located in an x/D relation corresponding to 249 from the pipe inlet, ensuring the complete development of the flow. The camera allowed a maximum acquisition velocity of 4500 frames per second. The superficial velocity range was 0.16–1.79m/s and 0.16–1.26m/s for air and water, respectively. To summarize, 165 tests were performed and 1320000 images were analyzed with 20 flow rate combinations. The computational application was validated by comparing it with the velocities measured manually over selected images. Results obtained were compared to several correlations such as Bendiksen [1], Cook & Behnia [2] and Wang et al. [3].

Sign in / Sign up

Export Citation Format

Share Document