Experimental Study of Low Liquid Loading Gas-Liquid Flow in Near-Horizontal Pipes

2001 ◽  
Author(s):  
Nicolas R. Olive ◽  
Hong-Quan Zhang ◽  
Clifford L. Redus ◽  
James P. Brill
Keyword(s):  
Flow Rate ◽  
Annular Flow ◽  
Film Flow ◽  
Phase Flow ◽  
Flow Loop ◽  
Liquid Holdup ◽  
Liquid Loading ◽  
Two Phase ◽  
Horizontal Pipes ◽  
Liquid Film Flow

Abstract Gas-liquid two-phase flow exists extensively in the transportation of hydrocarbon fluids. A more precise prediction of liquid holdup in near-horizontal, wet-gas pipelines is needed in order to better predict pressure drop and size downstream processing facilities. The most important parameters are pipe geometry (pipe diameter and orientation), physical properties of the gas and liquid (density, viscosity and surface tension) and flow conditions (velocity, temperature and pressure). Stratified flow and annular flow are the two flow patterns observed most often in near-horizontal pipelines under low liquid loading conditions. Low liquid loading is commonly referred to as cases in which liquid loading is less than 1,100 m3/MMm3 (200 bbl/MMscf). A previous study by Meng [1] was carried out on a new low liquid loading flow loop. A transparent test section (50.8-mm inner diameter and 19-m long) could be inclined within ± 2° from the horizontal. Mineral oil was used as the liquid and air was used as the gas phase. A surprising phenomenon was observed with air-oil flow; at high gas velocities (annular flow), liquid film flow rate, liquid holdup and pressure gradient decreased as liquid velocity increased. Low liquid loading gas-liquid two-phase flow in near-horizontal pipes was studied for air-water flow in the present study, in order to investigate the effects of the liquid properties on flow characteristics. This study was carried out on the same 2-in. ID flow loop used by Meng. The measured parameters included gas flow rate, liquid flow rate, pressure, differential pressure, temperature, liquid holdup, pipe wetted perimeter, liquid film flow rate, droplet entrainment fraction and droplet deposition rate. A new phenomenon was observed with air-water flow at low superficial velocities and with a liquid loading larger than 600 m3/MMm3. The liquid holdup increased as gas superficial velocity increased.

Experimental Study of Low Liquid Loading Gas-Liquid Flow in Near-Horizontal Pipes

2003 ◽  
Vol 125 (4) ◽  
pp. 294-298 ◽  
Author(s):  
Nicolas R. Olive ◽  
Hong-Quan Zhang ◽  
Qian Wang ◽  
Clifford L. Redus ◽  
James P. Brill
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Liquid Flow ◽  
Two Phase Flow ◽  
Liquid Density ◽  
Phase Flow ◽  
Liquid Holdup ◽  
Liquid Loading ◽  
Two Phase ◽  
Horizontal Pipes

Gas-liquid two-phase flow exists extensively in the transportation of hydrocarbon fluids. A more precise prediction of liquid holdup in near-horizontal, wet-gas pipelines is needed in order to better predict pressure drop and size downstream processing facilities. The most important parameters are pipe geometry (pipe diameter and orientation), physical properties of the gas and liquid (density, viscosity and surface tension) and flow conditions (velocity, temperature and pressure). Stratified flow and annular flow are the two flow patterns observed most often in near-horizontal pipelines under low liquid loading conditions. Low liquid loading is commonly referred to as cases in which liquid loading is less than 1,100m3/MMm3 (200 bbl/MMscf). Low liquid loading gas-liquid two-phase flow at −1° downward pipe was studied for air-water flow in the present study. The measured parameters included gas flow rate, liquid flow rate, pressure, differential pressure, temperature, liquid holdup, pipe wetted perimeter, liquid film flow rate, droplet entrainment fraction and droplet deposition rate. A new phenomenon was observed with air-water flow at low superficial velocities and with a liquid loading larger than 600m3/MMm3. The liquid holdup increased as gas superficial velocity increased. In order to investigate the effects of the liquid properties on flow characteristics, the experimental results for air-water flow are compared with the results for air-oil flow provided by Meng. (1999, “Low Liquid Loading Gas-Liquid Two-Phase Flow In Near-Horizontal Pipes,” Ph.D. Dissertation, U. of Tulsa.)

Study on Characteristics of Liquid Film Flow and Mass Transfer in Annular Two-Phase Flow

2017 ◽  
Vol 2017.22 (0) ◽  
pp. F112
Author(s):  
Takayuki YAMAGATA ◽  
Minoru KOMATSU ◽  
Nobuyuki FUJISAWA ◽  
Fumio INADA
Keyword(s):  
Mass Transfer ◽  
Liquid Film ◽  
Film Flow ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Two Phase ◽  
Liquid Film Flow

scholarly journals Liquid Film Flow Phenomena in Upwards Two-Phase Annular Flow

1973 ◽  
Vol 39 (317) ◽  
pp. 313-323 ◽  
Author(s):  
Kotohiko SEKOGUCHI ◽  
Kaneyasu NISHIKAWA ◽  
Masao NAKASATOMI ◽  
Hidetoshi NISHI ◽  
Akira KANEUZI
Keyword(s):  
Liquid Film ◽  
Annular Flow ◽  
Film Flow ◽  
Two Phase ◽  
Flow Phenomena ◽  
Liquid Film Flow

Gas-Liquid Two-Phase Flow Simulation of Wetted Wall Flows in Packed Columns

2010 ◽  
Author(s):  
Yoshiyuki Iso ◽  
Xi Chen
Keyword(s):  
Flow Rate ◽  
Liquid Flow ◽  
Film Flow ◽  
Liquid Flow Rate ◽  
Flow Simulation ◽  
Phase Flow ◽  
Flow Transition ◽  
Two Phase ◽  
Wall Flows ◽  
Rivulet Flow

Gas-liquid two-phase interfacial flows on the wall like liquid film flows, which are the so-called wetted wall flows, are observed in many industrial processes such as absorption, desorption, and distillation. For the optimum design of packed columns widely used in those kind of processes, the accurate predictions of the details on the small scale behavior of wetted wall flows in packing elements are very important, especially in order to enhance the mass transfer between the gas and liquid and to prevent flooding and channeling of the liquid flow. The present study focuses on the effects of the change of liquid flow rate and the wall surface texture treatments on the characteristics of wetted wall flows which have the drastic flow transition between the film flow and rivulet flow. In this paper, the three-dimensional gas-liquid two-phase flow simulation by using the volume of fluid (VOF) model is applied into wetted wall flows. Firstly, present results showed that the hysteresis of the flow transition between the film flow and rivulet flow arose against the increasing or decreasing stages of the liquid flow rate. It was supposed that this transition phenomenon depends primarily on the history of flow pattern as the change of curvature of interphase surface which leads to the surface tension. Additionally, the applicability and accuracy of the present numerical simulation were validated by using the existing experimental and theoretical studies. Secondary, referring to the texture geometry used in an industrial packing element, the present simulations showed that surface texture treatments added on the wall can improve the prevention of liquid channeling and can increase the wetted area.

Multi-Channel R134a Two-Phase Flow Measurement Technique for Automobile Air-Conditioning System

2003 ◽  
Author(s):  
Junjie Gu ◽  
Masahiro Kawaji ◽  
Tracey Smith-Pollard ◽  
James Cotton
Keyword(s):  
Flow Rate ◽  
Air Conditioning ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Flow Loop ◽  
Two Phase ◽  
Flow Area ◽  
Liquid Phases ◽  
Glass Tubes ◽  
Hot Film

This paper presents an improved on-line measurement technique developed to study two-phase flow rate distributions of refrigerants in parallel flow channels of compact heat exchangers and evaporators used in automotive air-conditioning systems. A prototype test station containing a refrigerant flow loop and a multi-channel two-phase flow measuring system, was designed and constructed based on the stratification of two-phase flow in horizontal tubes with relatively large diameters. In this work, glass tubes of 1”, 1.5” and 2” diameter were tested. Upon entering the glass tube, a vapour-liquid refrigerant mixture would readily stratify and the mean velocities of vapour and liquid phases could be measured separately using a hot film anemometer and an ultrasonic flow meter, respectively. Scales taped onto the glass tubes were also used to determine the mean liquid levels, from which the flow area of each phase could be calculated. The product of the flow area, phase density and mean phase velocity would then yield the mass flow rate of each phase. Validation experiments have been performed with R-134a as the working fluid and a 3-channel evaporator test section, designed with three separate outlets and kept under an adiabatic condition. The sum of the flow rates in the glass tubes for each phase was compared with the vapour or liquid flow rate determined from the total mass flow rate measured at the evaporator inlet and a heat balance in the pre-heater section of the pump-driven refrigerant flow loop. Validation tests yielded satisfactory results for both vapor and liquid phases, indicating the soundness of the measurement system based on the stratification tubes as well as the use of an ultrasonic flow meter and hot-film anemometer probes for phase average velocity measurements. The present measurement system has been equipped with seven glass tubes and thus can be used to study liquid and vapor flow rate distributions in commercial compact heat exchangers and improve their performance in automobile air conditioning systems.

Sign in / Sign up

Export Citation Format

Share Document