Analysis of Transient Gas-Liquid Two-Phase Flow in Pipelines

1988 ◽  
Vol 110 (2) ◽  
pp. 93-101 ◽  
Author(s):  
K. Kohda ◽  
Y. Suzukawa ◽  
H. Furukawa
Keyword(s):  
Natural Gas ◽  
Flow Rate ◽  
Two Phase Flow ◽  
Air Flow ◽  
Water Flow Rate ◽  
Mass Conservation ◽  
Phase Flow ◽  
Two Phase ◽  
Experimental Conditions ◽  
Natural Gas Pipelines

A new method is developed to analyze transient gas-liquid two-phase flow in natural gas pipelines. This method utilizes the two velocity mixture model to derive the basic equations. Also, a new model, which expresses phase conditions for multicomponent natural gas-condensate system, is presented to derive mass conservation equations for each hypothetical component. Transient air-water two-phase flow experiments were conducted using a test pipeline 105.3 mm in diameter and 1436.5 m long. Experimental conditions include, increasing or decreasing air flow rate with constant water flow rate, and transition from single-phase air flow to air-water two-phase flow. Experimental data were compared with calculated results, and the agreement was very good. Furthermore, calculated results agreed very well with a published field data.

Development of Air/Water Two-Phase Flow Centrifugal Pump and Its Operating Characteristics

2003 ◽  
Author(s):  
Akinori Furukawa ◽  
Satoshi Ohshita ◽  
Kusuo Okuma ◽  
Satoshi Watanabe
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Two Phase Flow ◽  
Air Flow ◽  
Water Flow Rate ◽  
Phase Flow ◽  
Air Flow Rate ◽  
Operating Characteristics ◽  
Two Phase ◽  
Flow Pump

A centrifugal impeller, the pumping action of which could be highly kept even at an air-water two-phase flow condition of inlet void fraction more than 30% in the region of relatively high water flow rate, has been developed. In the present paper, the design concept of two-phase flow impeller is described, at first, with experimental results. The short bladed forward impeller with high outlet blade angle was decided to keep theoretical head higher even in two-phase flow condition and to disperse the air accumulating region on the suction blade surface by the water jet flow coming from the pressure side. Furthermore, the tandem arrangement of outer and inner rotating cascades with the same blade numbers was adopted to suppress the rotating stall phenomena appearing in the case of a single stage of outer cascade. It should be noted that these results were obtained with operating a boost pump installed upstream of mixing section of air and water, that is not an actual operation of two-phase flow pump. Secondly, the operating characteristics of this two-phase flow pump with change of air flow rate were investigated experimentally without operating the boost pump. As the trajectory of operating point with increasing air flow rate appears along the resistance curve of piping system, the impossibility of pumping occurs at lower air flow rate even though pump head takes a positive value at high air flow rate with increasing water flow rate. It is recognized that it is necessary to improve two-phase flow head characteristic curves in the region of low water flow rate to operate in wider two-phase flow conditions.

Influences of Impeller Diameter and Diffuser Blades on Air-Water Two-Phase Flow Performance of Centrifugal Pump

2005 ◽  
Author(s):  
Naoki Matsushita ◽  
Akinori Furukawa ◽  
Kusuo Okuma ◽  
Satoshi Watanabe
Keyword(s):  
Centrifugal Pump ◽  
Water Flow ◽  
Flow Rate ◽  
Rotational Speed ◽  
Flow Condition ◽  
High Performance ◽  
Two Phase Flow ◽  
Water Flow Rate ◽  
Phase Flow ◽  
Two Phase

A tandem arrangement of double rotating cascades and single diffuser cascade, proposed as a centrifugal pump with high performance in air-water two-phase flow condition, yields lower head due to the smallness of the impeller outlet in comparison with a impeller with large outlet diameter and no diffuser. Influences of impeller diameter change and installation of diffuser blades on two-phase flow performance were experimentally investigated under the case of the same volute casing. As the result, the similarity law of the diameter of impeller having the similar blade geometry and the rotational speed is satisfied even in two-phase flow condition. Comparing pump performances between a large impeller without diffuser blades and a small one with diffuser blades, higher two-phase flow performance is obtained by controlling the rotational speed of a small impeller with diffuser blades in the range of small water flow rates, while a large impeller with no diffuser gives high performance in the range of high water flow rate and small air flow rate.

Analysis of Orifice Plate Differential Pressure Noise in Horizontal and Vertical Rising Gas-Water Two-Phase Flow

2010 ◽  
Author(s):  
Xianfa Li ◽  
Shuoping Zhong ◽  
Yanfei Sun
Keyword(s):  
Flow Rate ◽  
Two Phase Flow ◽  
Water Flow Rate ◽  
Differential Pressure ◽  
Orifice Plate ◽  
Vapor Flow ◽  
Phase Flow ◽  
Square Root ◽  
Two Phase ◽  
The Difference

It is an important achievement of modern techniques to determine the mass flow rate and the phase fraction of wet steam by measuring the orifice plate differential pressure noise. The orifice plate differential pressure noise of air-water two-phase flow in horizontal and vertical rising pipelines were analyzed. Kinds of calculation methods were tried to get the differential pressure noise. From the difference waveform of the differential pressure square root that the acquisition card got and the mean square root of the sample that got before, the first in first out (FIFO) principle was used to get the differential pressure noise. Result shows that the differential pressure noise has different level at different vapor flow rate with the same water flow rate, conclusions show that the two-parameter measurement by using orifice plate differential pressure noise may be possibly used in vertical rising gas-water two phase flow.

Experimental Study on the Void Fraction of Siphon Breaking Process

2017 ◽  
Author(s):  
Lei Xing-lin ◽  
Huang Shan-fan ◽  
Guo Zhong-xiao ◽  
Guo Xiao-yu
Keyword(s):  
Void Fraction ◽  
Flow Rate ◽  
Nuclear Power ◽  
Two Phase Flow ◽  
Water Flow Rate ◽  
Experimental Results ◽  
Physical Parameters ◽  
Phase Identification ◽  
Phase Flow ◽  
Two Phase

As a safety device to alleviate the loss of reactor coolant, the siphon breaking system is widely used in nuclear power plant. Researchers are very interested in this technique for its “passive” characteristic. Vertical downward air-water two-phase flow is encountered in the siphon breaking process. Previous researches have been more focused on some physical parameters, such as water flow rate, air flow rate, pressure drop and the undershooting height. Void fraction, as a key parameter in multiphase flow, should be studied in the siphon breaking phenomenon. Therefore, a needle-contact capacitance probe is used for flow-phase identification and a single-wire capacitance for obtaining the average value of gas distribution along the straight line. Experimental results show that the flow pattern during the vertical downward air-water two-phase flow is mostly annular flow. With the gas entering the pipeline, void fraction profile against time can be divided into three stages. The slope in the first stage is similar to that in the third. However, the slope slows down in the middle stage. The experimental results also show that the real duration time to break the siphon flow is as short as about 6 s. The void fraction at the end of the siphon breaking process is about 0.38. During this stage, a large amount of gas is sucked into the downcomer and little water is inhaled. The gas phase results in a convergent effect, where the air intake is the direct and fundamental reason of siphon breaking.

Study on Characteristics of Gas-Liquid Two Phase Flow Distribution in Vertical Manifolds

2010 ◽  
Author(s):  
Cheng Sheng ◽  
Tao Zhou ◽  
Liping Pang ◽  
Yanping Huang
Keyword(s):  
Flow Pattern ◽  
Flow Rate ◽  
Working Condition ◽  
Two Phase Flow ◽  
Water Flow Rate ◽  
Flow Distribution ◽  
Phase Flow ◽  
Two Phase ◽  
Rate Distribution ◽  
Two Phases

This paper shows the experiments of the flow rate distribution measurements of air-water two-phase flow in vertical multi-branch carried out on the Gas-liquid two-phase flow fluid and flow rate distribution experimental platform, and discusses the laws and the Characteristics of two phase flow distribution in the multi-branch by changing the water flow rate or the air flow rate under the condition of fix the flow rate of the other phase, then analyzes the degree of the flow deviation of both two phases in branches by calculating the standard deviations of each working condition. The experiments show that the flow distributions of both two phases are very uneven. There was much air but little water flows into the branches which were close to the inlets of the distributor, but in the branches which were far away from the inlets of the distributor, the situation was opposite to the previous one. The types of the flow pattern in each branch in every working condition were obtained through the Hewitt-Robert flow pattern picture. As the flow rate of air increased, the annular pattern would spread from the branches which are close to the inlets of the distributor to the ones which are far away from the inlets of the distributor.

scholarly journals Transient modeling of non-isothermal, dispersed two-phase flow in natural gas pipelines

2010 ◽  
Vol 34 (2) ◽  
pp. 495-507 ◽  
Author(s):  
Mohammad Abbaspour ◽  
Kirby S. Chapman ◽  
Larry A. Glasgow
Keyword(s):  
Natural Gas ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Gas Pipelines ◽  
Two Phase ◽  
Natural Gas Pipelines ◽  
Transient Modeling

scholarly journals Correction to Flow Rate Profile Interpretation for a Two-Phase Flow in Multistage Fractured Horizontal Wells by Inversion of DTS Data

ACS Omega ◽  
2020 ◽  
Vol 5 (41) ◽  
pp. 26955-26955
Author(s):  
Hongwen Luo ◽  
Beibei Jiang ◽  
Haitao Li ◽  
Ying Li ◽  
Zhangxin Chen
Keyword(s):  
Flow Rate ◽  
Two Phase Flow ◽  
Horizontal Wells ◽  
Phase Flow ◽  
Two Phase ◽  
Fractured Horizontal Wells ◽  
Rate Profile

scholarly journals Bubble behavior in horizontal two-phase flow under flow rate fluctuation

2014 ◽  
Vol 1 (4) ◽  
pp. TEP0019-TEP0019 ◽  
Author(s):  
Jun-ichi TAKANO ◽  
Hideaki MONJI ◽  
Akiko KANEKO ◽  
Yutaka ABE ◽  
Hiroyuki YOSHIDA ◽  
...  
Keyword(s):  
Flow Rate ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Bubble Behavior ◽  
Two Phase ◽  
Rate Fluctuation

Research on Two-Phase Flow Instability in Evaporator of Refrigeration System

2010 ◽  
Author(s):  
Nan Liang ◽  
Changqing Tian ◽  
Shuangquan Shao
Keyword(s):  
Pressure Drop ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Two Phase Flow ◽  
Density Wave ◽  
Phase Flow ◽  
Constant Mass ◽  
Refrigeration System ◽  
Two Phase

As one kind of fluid machinery related to the two-phase flow, the refrigeration system encounters more problems of instability. It is essential to ensure the stability of the refrigeration systems for the operation and efficiency. This paper presents the experimental investigation on the static and dynamic instability in an evaporator of refrigeration system. The static instability experiments showed that the oscillatory period and swing of the mixture-vapor transition point by observation with a camera through the transparent quartz glass tube at the outlet of the evaporator. The pressure drop versus mass flow rate curves of refrigerant two phase flow in the evaporator were obtained with a negative slope region in addition to two positive slope regions, thus making the flow rate a multi-valued function of the pressure drop. For dynamic instabilities in the evaporation process, three types of oscillations (density wave type, pressure drop type and thermal type) were observed at different mass flow rates and heat fluxes, which can be represented in the pressure drop versus mass flow rate curves. For the dynamic instabilities, density wave oscillations happen when the heat flux is high with the constant mass flow rate. Thermal oscillations happen when the heat flux is correspondingly low with constant mass flow rate. Though the refrigeration system do not have special tank, the accumulator and receiver provide enough compressible volume to induce the pressure drop oscillations. The representation and characteristic of each oscillation type were also analyzed in the paper.

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