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A Hybrid Scheme of Level Set and Diffuse Interface Methods for Simulating multi-phase Compressible flows

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Numerical Mathematics(Theory,Methods and Applications) 2022年第3期15卷 715-743页

作者： Meiyan Fu Tiao Lu School of Mathematical Sciences Peking UniversityBeijingChina Northwest Institute of Nuclear Technology Xi’anChina HEDPS&CAPT LMAM&School of Mathematical SciencesPeking UniversityBeijingChina

We propose a hybrid scheme combing the level set method and the multicomponent diffuse interface method to simulate complex multi-phase flows.The overall numerical scheme is based on a sharp interface framework where the level set method is adopted to capture the material interface,the Euler equation is used to describe a single-phase flow on one side of the interface and the six-equation diffuse interface model is applied to model the multi-phase mixture or gas-liquid cavitation on the other side.An exact Riemann solver,between the Euler equation and the six-equation model with highly nonlinear Mie-Gr¨uneisen equations of state,is developed to predict the interfacial states and compute the phase interface flux.Several numerical examples,including shock tube problems,cavitation problems,air blast and underwater explosion applications are presented to validate the numerical scheme and the Riemann solver.

关键词： multi-phase flow sharp interface diffuse interface level set six-equation model exact Riemann solver Mie-Gruneisen equation of state

Crude oil wax:A review on formation,experimentation,prediction,and remediation techniques

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Petroleum Science 2022年第5期19卷 2343-2357页

作者： Wyclif Kiyingi Ji-Xiang Guo Rui-Ying Xiong Li Su Xiao-Hui Yang Shi-Ling Zhang Unconventional Petroleum Research Institute China University of PetroleumBeijing102249China Sinopec Northwest Oil Field Branch UrumqiXinjiang830011China CNPC Engineering Technology R&D Company Limited BeijingChina

Wax deposition during crude oil production,transportation,and processing has been a headache since the early days of oil utilization.It may lead to low mobility ratios,blockage of production tubing/pipelines as well as fouling of surface and processing facilities,among others.These snags cause massive financial constraints increasing projects’turnover.Decades of meticulous research have been dedicated to this problem that is worth a review.Thus,this paper reviews the mechanisms,experimentation,thermodynamic and kinetic modeling,prediction,and remediation techniques of wax deposition.An overall assessment suggests that available models are more accurate for single than multi-phase flows while the kind of remediation and deployment depend on the environment and severity level.In severe cases,both chemical and mechanical are synergistically deployed.Moreover,future prospective research areas that require attention are proposed.Generally,this review could be a valuable tool for novice researchers as well as a foundation for further research on this topic.

关键词： Oil wax phase modeling Inhibitors Dispersants multi-phase flow

Numerical study on the dynamic characteristics of water entry of cavity body using two-phase SPH method

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Acta Mechanica Sinica 2021年第7期37卷 1072-1089,I0002页

作者： Qiuzu Yang Fei Xu Yang Yang Jingyu Wang Anwen Wang Chunhao Ma School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Engineering Technical University of Munich85748 GarchingGermany ASN Technology Group Co.Ltd Xi’an 710065China

The air usually has a major influence on the water entry of a typical cavity body(cavity body is a hollow,cylindrical,semiclosed structure),which not only lowers the slamming load but also affects the dynamic characteristics of water entry.In this paper,a two-phase smoothed particle hydrodynamics(SPH)model for simulating the water entry of cavity body is presented.The SPH model combined with Riemann solver is improved to deal with the two-phase flows with the discontinuous quantities across the interface.One-sided Riemann problem is used to impose the fluid–structure interaction and a switchfunction-based Riemann solver dissipation is formulated to improve the interfacial instability owing to the strong impact.The motion equations of rigid body are incorporated into two-phase SPH model to describe the motion of cavity body.The proposed model is validated by research on the test cases in the published literature.Finally,this work presents a study of water entry of cavity body by experiment and this two-phase SPH method.The dynamics phenomena in the coupling process between cavity body and two-phase flow are investigated.And the effects of air,mass,the sizes and incline angles of cavity body on the dynamic characteristics of cavity body and two-phase flows are shown.

关键词： Water entry Cavity body Dynamic characteristics multi-phase flow Smoothed particle hydrodynamics(SPH)

EXPERIMENTAL AND NUMERICAL INVESTIGATION OF BUBBLE AUGMENTED WATERJET PROPULSION

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Journal of Hydrodynamics 2012年第5期24卷 635-647页

作者： CHOI Jin-Keun SINGH Sowmitra HSIAO Chao-Tsung CHAHINE Georges L DYNAflow INC. JessupMarylandUSA

This contribution presents experimental and numerical investigations of the concept jet propulsion augmentation using bubble injection. A half-3D （D-shaped cylindrical configuration to enable optimal visualizations） divergent-convergent nozzle was designed, built, and used for extensive experiments under different air injection conditions and thrust measurement schemes. The design, optimization, and analysis were conducted using numerical simulations. The more advanced model was based on a two-way coupling between an Eulerian description of the flow field and a Lagrangian tracking of the injected bubbles using our Surface Averaged Pressure （SAP） model. The numerical results compare very favorably with nozzle experiments and both experiments and simulations validation the thrust augmentation concept. For a properly designed nozzle and air injection system, air injection produces net thrust augmentation, which increases with the rate of bubble injection. Doubling of thrust was measured for a 50% air injection rate. This beneficial effect remains at 50% after account for liquid pump additional work to overcome increased pressure by air injection.

关键词： waterjet propulsion bubble dynamics multi-phase flow

Progress in numerical simulation of cavitating water jets

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Journal of Hydrodynamics 2013年第4期25卷 502-509页

作者： PENG Guoyi SHIMIZU Seiji College of Engineering Nihon University

This paper reviews recent progress made toward modeling of cavitation and numerical simulation of cavitating water jets. Properties of existing cavitation models are discussed and a compressible mixture flow method for the numerical simulation of high- speed water jets accompanied by intensive cavitation is introduced. Two-phase fluids media of cavitating flow are treated as a homo- geneous bubbly mixture and the mean flow is computed by solving Reynolds-Averaged Navier-Stokes （RANS） equations for com- pressible fluid. The intensity of cavitation is evaluated by the gas volume fraction, which is governed by the compressibility of bubble-liquid mixture corresponding to the status of mean flow field. Numerical results of cavitating water jet issuing from an orifice nozzle are presented and its applicability to intensively cavitating jets is demonstrated. However, the effect of impact pressure caused by collapsing of bubbles is neglected, and effectively coupling of the present compressible mixture flow method with the dynamics of bubbles remains to be a challenge.

关键词： cavitation water jet multi-phase flow numerical simulation

A high precision computing method for heat transfer in the process of oil-water displacement

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Journal of Hydrodynamics 2021年第5期33卷 958-969页

作者： Pan-pan Han Ke Chen Dong-xi Liu Yun-xiang You Jin Wang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Yazhou Bay Institute of Deepsea Technology Shanghai Jiao Tong UniversitySanya 572000China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China COTEC Offshore Engineering Solutions Beijing 100011China

The process of oil-water displacement is one of the key technologies in offshore underwater tank.When hot oil is contacting the normal-temperature water,the interfacial heat transfer should be investigated as the heat loss may result in wax precipitation and solidification which will reduce the flowing of oil and thus affect the process.As for the numerical simulation of heat transfer,the calculation is costly as the underwater tank is usually large and the displacement period is long.A high precision computing method would greatly reduce the mesh scale.Therefore,this research is performed to establish a high precision computing solver.Based on volume of fluid(VOF),a new form of energy equation is proposed.This equation is derived from temperature equation and the variable internal energy per volume is used.This variable is additive and has a close relationship with volume fraction.With algorithm implantation to OpenFOAM,two non-isothermal VOF solvers are established corresponding to temperature equation and the new equation respectively.After an analytical solution is built,the two solvers are compared.The solver based on the new equation presents far more accurate results than the solver based on temperature equation.An energy weighted scheme is more reasonable than a linear temperature distribution for the mixture phase.

关键词： multi-phase flow energy equation heat transfer oil-water displacement volume of fluid(VOF)

multi-scale HPC system for multi-scale discrete simulation—Development and application of a supercomputer with 1 Petaflops peak performance in single precision

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Particuology 2009年第4期7卷 332-335页

作者： Feiguo Chen Wei Ge Li Guo Xianfeng He Bo Li Jinghai Li Xipeng Li Xiaowei Wang Xiaolong Yuan State Key Laboratory o fmulti-phase Complex System Institute of Process Engineering Chinese Academy of Sciences P.O. Box 353 Beijing 100190 China

A supercomputer with 1.0 Petaflops peak performance in single precision, designed and established by Institute of Process Engineering, Chinese Academy of Sciences, is introduced in this brief communication. A designing philosophy utilizing the similarity between hardware, software and the problems to be solved is embodied, based on the multi-scale method and discrete simulation approaches developed at Institute of Process Engineering （IPE） and implemented in a graphic processing unit （GPU）-based hybrid computing mode. The preliminary applications of this machine in areas of multi-phase flow, molecular dynamics and so on are reported, demonstrating the supercomputer as a paradigm of green computation in new architecture.

关键词： High-performance computing （HPC） Graphic processing unit （GPU） Lattice Boltzmann method Molecular dynamics multi-phase flow multi-scale method Particle method

Numerical modelling of the hybrid rocket engine performance

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Propulsion and Power Research 2021年第1期10卷 15-22页

作者： Marian Gieras Aleksander Gorgeri a Institute of Heat Engineering Warsaw University of TechnologyWarsaw00-665Poland Łukasiewicz Research Network e Institute of Aviation Warsaw02-256Poland

The purpose of this paper is to present method of the numerical modeling of the hybrid rocket engine's work as a tool for designing engines of this type.The model is intended as an accurate and simple to use development tool for use in preliminary design stages of hybrid rocket engines,improving the effectiveness and quality of this process.General assumptions underlying the use of a model are presented,together with an analysis of past work in this field.Results of an extensive experimental campaign are presented and compared with the results of numerical modelling in order to calibrate the proposed model and evaluate its accuracy.Parameter variation and optimization were conducted,proving functionality of the methodology.Presented numerical calculations show that the adopted approach to reduce the analysis time and complexity was correct.This method of numerical calculation of hybrid engine working parameters combines aspects of accuracy and simplicity at the early design stage to avoid timeconsuming and costly changes in subsequent detailed stages of design.

关键词： Hybrid rocket engine Combustion multi-phase flow Regression Specific impulse

二氧化碳在York地层中埋存的地球化学模拟(英文)

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Chinese Journal of Chemical Engineering 2011年第6期19卷 1052-1059页

作者：杨子浩金敏李明远董朝霞闫鹏 Enhanced Oil Recovering Center China University of Petroleum(Beijing) Institute of Petroleum Engineering Heriot-Watt University

In this paper, we build up a three-dimensional model for CO2 storage in the deep reservoir. And this paper gives the mathematical formalism of combined geochemical and multi-phase flow. The results give us the information about geochemical changing caused by CO2 injection into aqueous, the dissolution or precipitation of reservoir minerals caused by aqueous components change, the change of water density, also the differences between this model and the simulation model without considering geochemical. The basic data for simulation is from York Reservoir.

关键词： CO2 storage geochemical reactions multi-phase flow numerical simulation York reservoir