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Applied Mathematics and Mechanics(English Edition) 2006年第10期27卷 1373-1381页

作者：曾卓雄周力行刘志和 Department of Engineering Mechanics Tsinghua UniversityBeijing 100084P.R.China Department of Mechanical EngineeringNanchang Institute of Aeronautical TechnologyNanchang 330034P.R.China Department of Mechanical Engineering Nanchang Institute of Aeronautical TechnologyNanchang 330034P.R.China

The USM-θ model of Bingham fluid for dense two-phase turbulent flow was developed, which combines the second-order moment model for two-phase turbulence with the particle kinetic theory for the inter-particle collision. In this model, phases interaction and the extra term of Bingham fluid yield stress are taken into account. An algorithm for USM-θ model in dense two-phase flow was proposed, in which the influence of particle volume fraction is accounted for. This model was used to simulate turbulent flow of Bingham fluid single-phase and dense liquid-particle two-phase in pipe. It is shown USM-θ model has better prediction result than the five-equation model, in which the particle-particle collision is modeled by the particle kinetic theory, while the turbulence of both phase is simulated by the two-equation turbulence model. The USM-θ model was then used to simulate the dense two-phase turbulent up flow of Bingham fluid with particles. With the increasing of the yield stress, the velocities of Bingham and particle decrease near the pipe centre. Comparing the two-phase flow of Bingham-particle with that of liquid-particle, it is found the source term of yield stress has significant effect on flow.

关键词： Bingham fluid two-phase flow yield stress second-order moment model

Coriolis flowmeter for two-phase flow Measurement Based on TCN-LSTM

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Coriolis Flowmeter for Two-Phase Flow Measurement Based on T...

BASIC EQUATIONS AND WAVE THEORY OF GAS-LIQUID two-phase TRANSIENT flow

第43届中国控制会议

作者： Lijun Sun Zihui Zhao Haiming Wang Xuan Zhuang School of Electrical Automation and Information Engineering

Coriolis flow meters,are extensively utilized for directly measuring the mass flow of fluids across various ***,achieving high-accuracy measurements in two-phase flow remains an unresolved *** study evaluates several commonly used time series models with different signal lengths for input feature variables,aiming to compare their dynamic following capabilities and prediction ***,a composite model,TCN-LSTM,is introduced to enhance predictive accuracy and tracking *** performance of TCNLSTM is assessed through both offline and online prediction *** prediction experiments include both static and dynamic *** online static prediction experiment assesses TCN-LSTM's prediction ability under relatively stable operating *** online dynamic prediction experiment provides a horizontal comparison and better prediction between the prediction accuracy and follow-up prediction ability of TCN-LSTM and the Stacking model proposed in [4].The result indicates that TCN-LSTM have a better prediction performance.

关键词： Coriolis Mass flowmeter two-phase flow TCN LSTM

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Journal of Hydrodynamics 1992年第1期4卷 83-90页

作者： Yang, Jiandong Wu, Rongqiao Chen, Jiznzhi Wuhan Univ of Hydraulic and Electric Engineering Wuhan China

This paper systematically discussed the equations for two-phase transient flow and pressure wave and interfacial wave. The behaviour of basic equations was analyzed. The formulas for the wave speed of the pressure wave and the interfacial wave were derived. It was proved that various mathematical models can be uniformed by the integrating model and various wave speed formulas can be uniformed by the universal formula derived. The basic equations for the separated flow model are ill-conditioned because of the unreasonable neglect of the pressure differences between the phases and interfaces. Drift flux model can improve the accuracy if some additional equations are provided. The basic equations for homogeneous flow model are well-conditioned and they can be used in two-phase transient flow, especially in the cases of no velocity slips between various phases fluid.

关键词： wave theory two-phase flow mathematical model

Numerical simulation of two-phase flow field in underwater sealing device based on dynamic mesh

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Journal of Measurement Science and Instrumentation 2015年第3期6卷 253-257页

作者：张学伟李强吕梦柔中北大学机电工程学院山西太原030051

In order to speed underwater launch of minor-caliber weapons,a sealing device can be set in front of underwater muzzle to separate water,preventing the muzzle from water *** establishing and simplifying the model of underwater weapon sealing device and unstructured mesh computing domain model based on computational fluid dynamics（CFD）,dynamic mesh and user defined function（UDF）,the N-S equation is solved and the numerical analysis and calculation of the complex two-phase flow inside the sealing device are carried *** results show that the gas discharged from the sealing device is conducive to the formation of the projectile *** the projectile is launched at 5munder water,the shock wave before and after the projectile has impact on the box body up to 100 MPa,therefore the sealing device must be strong *** research results have the vital significance to the design of underwater weapon sealing device and the formation of the projectile supercavitation.

关键词： two-phase flow supercavitation sealing device computational fluid dynamics(CFD) dynamic mech

flow pattern and pressure drop of gas-liquid two-phase swirl flow in a horizontal pipe

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Journal of Central South University 2019年第9期26卷 2528-2542页

作者： RAO Yong-chao DING Bo-yang WANG Shu-li WANG Zi-wen ZHOU Shi-dong Jiangsu Key Laboratory of Oil-gas Storage and Transportation Technology Changzhou 213016China School of Petroleum Engineering Changzhou UniversityChangzhou 213016China

The gas-liquid two-phase swirl flow can increase the gas-liquid two-phase contact area and enhance the heat and mass transfer efficiency between gas and *** swirl flow has important practical application value for promoting gas hydrate formation and ensuring the flow safe of natural gas hydrate *** experimental section was made of plexiglass pipe and the experimental medium was air and *** flow pattern of the gas-liquid two-phase swirl flow in the horizontal pipe was divided,according to a high-definition camera and the overall characteristics of the gas-liquid *** flow pattern map of the gas-liquid two-phase swirl flow in a horizontal pipe was *** influence of the flow velocity and vane parameters on pressure drop was *** types of gas-liquid two-phase swirl flow pressure drop models was *** homogeneous-phase and split-phase pressure drop models have good prediction on swirl bubble flow,swirl dispersed flow,swirl annular flow and swirl stratified flow,and the predictive error band is not more than 20%.

关键词： swirl flow two-phase flow flow pattern swirl number pressure drop

Time-Frequency Signal Processing for Gas-Liquid two phase flow Through a Horizontal Venturi Based on Adaptive Optimal-Kernel Theory

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Chinese Journal of Chemical Engineering 2011年第2期19卷 243-252页

作者：孙斌王二朋丁洋白宏震黄咏梅 College of Metrological Technology and Engineering China Jiliang University Hangzhou 310018 China

A time-frequency signal processing method for two-phase flow through a horizontal Venturi based on adaptive optimal-kernel （AOK） was presented in this ***,the collected dynamic differential pressure signal of gas-liquid two-phase flow was preprocessed,and then the AOK theory was used to analyze the dynamic differ-ential pressure *** mechanism of two-phase flow was discussed through the time-frequency *** the condition of steady water flow rate,with the increasing of gas flow rate,the flow pattern changes from bubbly flow to slug flow,then to plug flow,meanwhile,the energy distribution of signal fluctuations show significant change that energy transfer from 15-35 Hz band to 0-8 Hz band;moreover,when the flow pattern is slug flow,there are two wave peaks showed in the time-frequency ***,a number of characteristic variables were defined by using the time-frequency spectrum and the ridge of *** the characteristic variables were visu-ally analyzed,the relationship between different combination of characteristic variables and flow patterns would be *** results show that,this method can explain the law of flow in different flow *** characteristic variables,defined by this method,can get a clear description of the flow *** method provides a new way for the flow pattern identification,and the percentage of correct prediction is up to 91.11%.

关键词： adaptive optimal-kernel two-phase flow time-frequency spectrum time-frequency ridge flow pattern identification

Effects of the outlet pressure on two-phase slug flow distribution uniformity in a multi-branch microchannel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第1期23卷 68-82页

作者： Peng-fei ZHANG Xiang-guo XU Yong-jun HUA Yu-qi HUANG Department of Energy Engineering Zhejiang UniversityHangzhou310027China Center for Balance Architecture Zhejiang UniversityHangzhou310027China State Key Laboratory of Clean Energy Utilization Department of Energy EngineeringZhejiang UniversityHangzhou310027China

The two-phase flow maldistribution phenomenon in microchannels with multi-parallel branches is inevitable in almost all common conditions,and not only affects the performance of the facility but also increases the risk of system *** order to better understand the distribution mechanism and to explore a potential strategy to improve uniformity,the pressure evolutions under different split modes in a microchannel with multi-parallel branches,were analyzed *** results show that the fluctuations of transient pressure exhibit similar trends at various split modes,but the time-averaged pressure drops in the branches are very *** may be related to the maldistribution of mass ***,the outlet pressures of the branches are numerically changed to explore the relationship between differential pressure and flow *** this study,the flow distribution is seen to display a strong sensitivity to the branch differential *** changing the pressure conditions,the gas flow of the middle branch can be effectively prevented from the main channel,and the flow type in this branch turns from gas-liquid to a single liquid *** the differential pressure of the first branch channel changes,the maldistribution phenomenon of the model can be mitigated to a certain *** on this,by adjusting the differential pressures of the second branch,the maldistribution phenomenon can be further mitigated,and the normalized standard deviation(NSTD)decreases from 0.52 to approximately *** results and conclusions are useful in understanding the two-phase flow distribution mechanism and for seeking optimizing strategies.

关键词： two-phase flow Multi-parallel microchannel flow distribution Slug flow Split modes

Measurement for Water Content in Oil-Water two phase flow Based on Novel Hybrid Intelligent Prediction Model

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Measurement for Water Content in Oil-Water Two Phase Flow Ba...

Gas Condensate two phase flow Performance in Porous Media Considering Capillary Number and Non-Darcy Effects

第二十六届中国控制会议

作者： Zhang Dongzhi,Xia Bokai,Fu Tao College of Information and Control Engineering,China University of Petroleum(East China),Dongying 257061,P.R.China

Some parameters affecting the measurement of water content in oil/water two-phase flow are detected using multi-sensor technology,and a novel hybrid intelligent prediction model is proposed to improve measuring precision of water *** advanced information processing technologies,such as neural networks optimized by hybrid genetic algorithm,combined method for decisions of multiple sub-modules,are introduced in this intelligent prediction model,which guarantee a good prediction effect with global and fast convergence,strong generalization capability and high *** research re-sult in this paper indicates that prediction precision is improved to a great extent in the all-round measuring range for water content,while the development cost is at a low *** is a new and effective method for measuring water content in oil/water two-phase flow.

关键词： two-phase flow Multi-sensor Neural Network Intelligent Prediction

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Petroleum Science 2004年第3期1卷 49-55页

作者：覃斌李相方程时清石油大学(北京) 中国北京昌平区102249

Retrograde condensation frequently occurs during the development of gas condensate reservoirs. The loss of productivity is often observed due to the reduced relative permeability to gas as condensate accumulates near the well bore region. How to describe the condensate blockage effect exactly has been a continuous research topic. However, up to now, the present methods usually over-estimate or underestimate the productivity reduction due to an incorrect understanding of the mechanism of flow in porous medium, which inevitably results in an inaccurate prediction of production performance. It has been found in recent numerous theoretical and experimental studies that capillary number and non-Darcy flow have significant influence on relative permeability in regions near the well bore. The two effects impose opposite impacts on production performance, thus leading to gas condensate flow showing characteristics different from general understanding. It is significant for prediction of performance in gas condensate wells to understand the two effects exactly. The aim of the paper is to describe and analyze the flow dynamics in porous media accurately during the production of gas condensate reservoirs. Based on the description of three-zone flow mechanism, capillary number and non-Darcy effect are incorporated in the analysis of relative permeability, making it possible to describe the effect of condensate blockage. The effect of capillary number and inertial flow on gas and condensate relative permeability is analyzed in detail. Novel Inflow Performance Relation (IPR) models considering high velocity effects are formulated and the contrast analysis of different IPR models is conducted. The result shows that the proposed method can help predict the production performance and productivity more accurately than conventional methods.

关键词： Gas condensate two-phase flow porous media capillary number non-Darcy effect