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Machine learning methods for predicting CO_(2) solubility in hydrocarbons

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Petroleum Science 2024年第5期21卷 3340-3349页

作者： Yi Yang Binshan Ju Guangzhong lü Yingsong huang School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Key laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationBeijing100083China Key laboratory of Geological Evaluation and Development Engineering of Unconventional Natural Gas Energy Beijing100083China Shengli Oilfield Company SINOPECDongying257015ShandongChina

The application of carbon dioxide(CO_(2)) in enhanced oil recovery(EOR) has increased significantly, in which CO_(2) solubility in oil is a key parameter in predicting CO_(2) flooding performance. Hydrocarbons are the major constituents of oil, thus the focus of this work lies in investigating the solubility of CO_(2) in hydrocarbons. However, current experimental measurements are time-consuming, and equations of state can be computationally complex. To address these challenges, we developed an artificial intelligence-based model to predict the solubility of CO_(2) in hydrocarbons under varying conditions of temperature, pressure, molecular weight, and density. Using experimental data from previous studies,we trained and predicted the solubility using four machine learning models: support vector regression(SVR), extreme gradient boosting(XGBoost), random forest(RF), and multilayer perceptron(MlP).Among four models, the XGBoost model has the best predictive performance, with an R^(2) of ***, sensitivity analysis and evaluation of the relative impacts of each input parameter indicate that the prediction of CO_(2) solubility in hydrocarbons is most sensitive to pressure. Furthermore, our trained model was compared with existing models, demonstrating higher accuracy and applicability of our model. The developed machine learning-based model provides a more efficient and accurate approach for predicting CO_(2) solubility in hydrocarbons, which may contribute to the advancement of CO_(2)-related applications in the petroleum industry.

关键词： CO_(2)solubility Machine learning Support vector regression Extreme gradient boosting Random forest Multi-layer perceptron

Nonplanar flow-induced vibrations of a cantilevered PIP structure system concurrently subjected to internal and cross flows

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Acta Mechanica Sinica 2019年第6期35卷 1241-1256页

作者： z.Y.liu T.l.Jiang l.Wang H.l.Dai Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

Pipe-in-pipe(PIP)structures are widely used in offshore oil and gas pipelines to settle thermal insulation issues.A PIP structure system usually consists of two concentric pipes and one softer layer for thermal insulation *** total response of the system is related to the dynamics of both pipes and the interactions between these two concentric *** the current work,a theoretical model for flow-induced vibrations of a PIP structure system is proposed and analyzed in the presence of an internal axial flow and an external cross *** interactions between the two pipes are modeled by a linear distributed damper,a linear distributed spring and a nonlinear distributed spring along the pipe *** unsteady hydrodynamic forces due to cross flow are modeled by two distributed van der Pol wake *** nonlinear partial differential equations for the two pipes and the wake are further discretized by the aid of Galerkin’s technique,resulting in a set of ordinary differential *** ordinary differential equations are further numeri cally solved by using a fourth-order Runge-Kutta integration *** portraits,bifurcation diagrams,an Argand diagram and oscillation shape diagrams are plotted,showing the existence of a lock-in phenomenon and figure-of-eight *** PIP system subjected to cross flow displays some interesting dynamical behaviors different from that of a single-pipe structure.

关键词： Cantilevered PIP structure Theoretical model Flow-induced vibration Cross flow Internal flow

Coarsening Behavior of Gamma Prime Precipitates in a Nickel Based Single Crystal Superalloy

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Journal of Materials Science & Technology 2016年第2期32卷 172-176页

作者： S.Tang l.K.Ning T.z.Xin z.zheng University of Chinese Academy of Sciences.Beijing 100049.China Superalloy Division.Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The γ/γ＇ microstructural evolution in a nickel based single crystal superalloy during load-free thermal exposure at 900 ℃ has been further investigated in this paper. The growth characteristics of γ＇ precipitates were discussed in detail. The generation of interfacial dislocations would accelerate the rate of coalescence in the dendrite arms. The average sizes of precipitates were used to compare interface with diffusion controlled growth mechanism and no mechanism seems obviously dominant, although the square rate law gives slightly better fit. The coarsening behavior may be controlled by diffusion through the ragged interface between the γ＇ precipitate and the y matrix.

关键词： Single crystal superalloy Coarsening Interfacial dislocations Rate controlling mechanism

Constitutive equation and model validation for a 31 vol.% B_4Cp/6061Al composite during hot compression

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Journal of Materials Science & Technology 2018年第10期34卷 1730-1738页

作者： l. zhou C. Cui Q.z. Wang C. li B.l. Xiao z.Y. Ma Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Electromechanical and Vehicle Engineering Yantai University Yantai 264005 China School of Mechanical Engineering Shenyang Ligong University Shenyang 110159 China Nuclear and Radiation Safety Center Ministry of Environmental Protection Beijing 100082 China

An accurate constitutive equation is essential to understanding the flow behavior of B4C/A1 compos-ites during the hot deformation. However, the constitutive equations developed previously in literature are generally for low strain rate deformation. In the present work, we modified the general consti-tutive equation and take the high strain rate correction into account. The constitutive equation for a 31 vol.% B4Cp/6061AI composite was constructed based on the flow stresses measured during isothermal hot compression at temperatures ranging from 375 to 525 ℃ and strain rates from 0.01 to 10 s^-1. The experimental flow stresses were corrected by considering temperature-dependent Arrhenius factor. The modified equation was then verified by using DEFORM-3D finite element analysis to simulate the exper-imental hot compression process. The results show that the modified equation successfully predicts flow stress, load-displacement, and the temperature rise. This helps to optimize the hot deformation process, and to obtain desirable properties, such as reduced porosity and homogenous particle distribution in B4C/AI composites.

关键词： Composites B4C/AI Constitutive equation Hot compression Finite element simulation

Effect of Carbon Nanotube Orientation on Mechanical Properties and Thermal Expansion Coefficient of Carbon Nanotube-Reinforced Aluminum Matrix Composites

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Acta Metallurgica Sinica(English letters) 2014年第5期27卷 901-908页

作者： z.Y.liu B.l.Xiao W.G.Wang z.Y.Ma School of Materials Science and Engineering Dalian University of Technology Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences School of Mechanical Engineering Liaoning Shihua University

Carbon nanotube-reinforced 2009Al （CNT/2009Al） composites with randomly oriented CNTs and aligned CNTs were fabricated by friction stir processing （FSP） and FSP-rolling, respectively. The CNT/2009A1 composites with aligned CNTs showed much better tensile properties at room temperature and elevated temperature compared with those with the randomly oriented CNTs, which is mainly attributed to larger equivalent aspect ratio of the CNTs and avoidance of preferential fracture problems. However, much finer grain size was not beneficial to obtaining high strength above 473 K. The aligned CNTs resulted in tensile anisotropy, with the best tensile properties being achieved along the direction of CNT aligning. As the off-axis angle increased, the tensile properties were reduced due to the weakening of the load transfer ability. Furthermore, aligned CNTs resulted in much lower coefficient of thermal expansion compared with randomly oriented CNTs.

关键词： Carbon nanotubes Metal matrix composites Mechanical properties Coefficient of thermalexpansion Friction stir processing

RESEARCH ON lASER DIRECT DEPOSITION PROCESS OF Ti-6Al-4V AllOY

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Acta Metallurgica Sinica(English letters) 2007年第3期20卷 171-180页

作者： S.Y. Gao Y.z. zhang l.K. Shi B.l. Du M.z. Xi H.z. Ji Mechanical Engineering College Yanshan University O~mhuangdao 066004 China Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

laser direct deposition （lDD） of metallic components is an advanced technology of combining CAD/CAM （computer aided design/computer aided manufacturing）, high power laser, and rapid prototyping. This technology uses laser beam to melt the powders fed coaxiaUy into the molten pool by the laser beam to fabricate fuUy dense metallic components. The present article mainly studies the lDD of Ti-6Al-4V alloy, which can be used to fabricate aircraft components. The mechanical properties of the Ti-6Al-4V alloy, fabricated by lDD, are obtained using the tension test, and the oxygen content of used powders and deposited specimens are measured. In the present article, it can be seen that the mechanical properties obtained using this method are higher than the ones obtained by casting, and equal to those got by wrought anneal. One aircraft part has been made using the lDD process. Because of this aircraft part, with sophisticated shape, the effect of the laser scanning track on the internal soundness of the deposited part was discussed.

关键词： laser direct deposition Ti-6Al-4V alloy mechanical property depositing process aircraft component

More Feasible Way to Cleave Photo-labile Resin

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Chinese Chemical letters 1996年第10期7卷 909-910页

作者： Wang, DX Guo, YH huang, l CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA XUANWU HOSP BEIJING GERIATR INSTBEIJING 100053PEOPLES R CHINA

A combinatorial cleavage, acidolysis-saponification, after solid phase peptide synthesis on photo-labile resin was stated in present paper. Peptide (Gly-Asp-Ala-lys-Gly)(2)>lys-OH was liberated with high yield(92.1%) and excellent purity(91.6%) from its protected peptidyl nitro-resin precursor by a new orthorgonal protocol: 1) Hi-TFMSA, 2) 0.2N NaOH/90% EtOH.

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INFlUENCE OF lOCAl BRITTlE zONE ON THE FRACTURETOUGHNESS OF HIGH-STRENGTH lOW-AllOYEDMUlTIPASS WElD METAlS

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Acta Metallurgica Sinica(English letters) 1998年第2期11卷 87-92页

作者： z.l.zhou S.H.liu Dalian Railway Inst Dalian China

In this paper, toughness properties and microstructurc of low-alloyed multipass welds with yield strength above 700MPa have 6een studied using the weld thermal simulation and throughout thickness CTOD fracture mechanics tests. Impact testing of thermal simulated specimens showed that the primary weld metal and the fine gmmed weld metal had good toughness, while the coarse grained weld metal had the lowest toughness value as the local brittle zone (lBz) in multipass weld metals. Cleavage fracture in CTOD testing of thick multipass weld metals was initiated from martensite-austenite (MA) phases in the lBz. MA phases were distributed at the prior austenite grain boundaries and around ferrite grains. As the size of the local brittle zone along the fatigue crack front increases, CTOD frncture toughness of multipass weld metals decreases. The weakest link theory was used to evaluate effect of the local brittle zone on fracture toughness of thick multipass weld metals. The estimated curves agree well with the eaperimental data.

关键词： multipass weld metal local brittle zone weld thermal simulation CTOD fracture toughness

NUMERICAl SIMUlATION OF SUCCINONITRITE DENDRITIC GROWTH IN A FORCED FlOW

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Acta Metallurgica Sinica(English letters) 2008年第6期21卷 444-450页

作者： z. Chen C.l. Chen l.M. Hao School of Science Department of Applied Physics Shaanxi Key Laboratory of Condensed Matter Structures and Properties Northwestern Polytechnical University Xi＇an 710072 China School of Science Xi＇an University of Science ＆ Technology Xi＇an 710054 China

Numerical simulation based on phase field method is performed to describe solidification process of pure material in a free or forced flow. The evolution of the interface is showed, and the effects of mesh grid and flow velocity on succinonitrite shape are studied. These results indicate that crystal grows into an equiaxial dendrite in a free flow and into an asymmetrical dendritic in a forced flow. With increasing flow velocity, the upstream dendritic arm tip grows faster and the downstream arm grows slower. However, the evolution of the perpendicular tip has no significant change. In addition, mesh grid has no influence on dendritic growth shape when mesh grid is above 300×300.

关键词： Phase field method Forced flow Dendritic Succinonitrite Tip velocity