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Research on physical explosion crater model of high-pressure natural gas pipeline

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PETROLEUM RESEARCH 2024年第3期9卷 432-438页

作者： Wang, Dongyuan Xu, Shuiying Wang, Zhao Zhou, Yazhe Gao, Na China Petr Pipeline Engn Corp Langfang Peoples R China PipeChina Engn technol Innovat Co Ltd Tianjin Peoples R China Univ sci & technol Beijing Sch Civil & Resource Engn Beijing Peoples R China China Petr Pipeline Bur Engn Co Ltd Int Business Dept Langfang Peoples R China

In this study, Hypermesh and LS-DYNA numerical simulation software are used to build a multi domain coupling model of natural gas pipeline, including soil, pipeline, TNT explosive and air domain, and the non-reflection boundary conditions are set for the model. The TNT equivalent method is used to convert the physical explosion amount of natural gas pipeline into 1387.38 kg TNT explosive amount. The simulation results show that the physical explosion of pipeline forms an approximate elliptical crater with a width of 12.68 m and a depth of 4.12 m; the TNT equivalent of the model is corrected by comparing the crater simulation value and the size value of the crater calculated by the PRCI empirical formula under the same laying condition, and the correction coefficient is selected as 0.9, and the corrected TNT equivalent is 1248.64 kg; the modified model crater size is 3.72 m deep and 12.66 m wide, compared with the crater size obtained from the field test, the error of crater depth and width calculated by the modified model simulation is 5.7% and 15.5% respectively. (c) 2024 The Authors. Publishing services provided by Elsevier B.V. on behalf of KeAi Communication Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/licenses/ by-nc-nd/4.0/).

关键词： High-pressure natural gas Pipeline Physical explosion Crater Numerical simulation

Properties of the phase diagram from the Nambu-Jona-Lasino model with a scalar-vector interaction

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NUCLEAR sciENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Yang, Yong-Hang Liu, He Chu, Peng-Cheng Qingdao Univ technol Sch Sci Qingdao 266520 Peoples R China Qingdao Univ technol Res Ctr Theoret Phys Qingdao 266033 Peoples R China

We investigated the properties of the phase diagram of high-order susceptibilities, speed of sound, and polytropic index based on an extended Nambu-Jona-Lasinio model with an eight-quark scalar-vector interaction. Non-monotonic behavior was observed in all these quantities around the phase transition boundary, which also revealed the properties of the critical point. Further, this study indicated that the chiral phase transition boundary and critical point could vary depending on the scalar-vector coupling constant GSV\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$G_\text {SV}$$\end{document}. At finite densities and temperatures, the negative GSV\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$G_\text {SV}$$\end{document} term exhibited attractive interactions, which enhanced the critical point temperature and reduced the chemical potential. The GSV\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$G_\text {SV}$$\end{document} term also affected the properties of the high-order susceptibilities, speed of sound, and polytropic index near the critical point. The non-monotonic (peak or dip) structures of these quantities shifted to a low baryon chemical potential (and high temperature) with a negative GSV\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$G_\te

关键词： QCD phase diagram High-order susceptibilities Speed of sound Polytropic index NJL model QUANTUM CHROMODYNAMICS TRANSITION STATE

Study on Co-Permeation of Solid Rare Earth, Boron and Vanadium

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Journal of Rare Earths 2001年第2期19卷 149-152页

作者：陶小克董桂霞彭日升孙永昌 tianjin inst technol Dept Mat Sci & Engn Tianjin 300191 Peoples R China

The effect of rare earth compound of CeCl3 on the kinetic process, composition, microstructure and mechanical properties of co-permeating of solid powder boron-vanadium (B-V) was investigated. The results indicate that the addition of CeCl3 to permeating agent not only has obviously catalytic effect on permeating rate, which increases by more than 40%, hut also greatly improves the hardness and abrasion resistant of the permeating layer owing to the formation of new phase of CeFe2 after Ce permeates into the layer of the part as an alloying ingredient. It is believed that rare earth elements accelerate the permeating rate of B and V by increasing the potentials of B and V of the agent, activating the surface of the workpiece, and decreasing the activation energy of diffusion of the B and V atoms.

关键词： rare earths boron potential vanadium potential co-permeation of rare earth boron and vanadium

Application of Magnetic Treatment in Hot Water Boilers for Preventing Scale

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Journal of Materials science & technology 1999年第6期15卷 575-577页

作者： Geng, DY Zhang, ZD Cui, BZ Guo, ZJ Liu, W Zhao, XG Liu, JW Chinese Acad sci Inst Met Res Shenyang 110015 Peoples R China tianjin inst technol Tianjin 300191 Peoples R China

The application of magnetic treatment technology to hot water recirculating systems resulted in a reduction in scale deposited on the inside pipe walls by changing the formation of scale from its solid form to slag. T... 详细信息

关键词： exp Application of Magnetic Treatment in Hot Water Boilers for Preventing Scale

Study on Mg PSZ Ceramics Doped with Y_2O_3 and CeO_2

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Journal of Rare Earths 2000年第2期18卷 105-109页

作者：马亚鲁袁启明谈家琪 tianjin Univ Dept Mat Sci & Technol Tianjin 300072 Peoples R China tianjin Univ Dept Chem Tianjin 300072 Peoples R China

Mg PSZ ceramics doped with Y 2O 3 and CeO 2 was prepared using traditional processing method. The fine grain PSZ ceramics( d c10 μm) sintered at low temperature(1550 ℃) was obtained by means of composition design. The effects of co stabilization of Y 2O 3, CeO 2 and annealing at 1100 ℃ on material composition, microstructure and mechanical properties were studied. The results show that Y 2O 3 and CeO 2 during annealing at 1100 ℃ can inhibit subeutectoid decomposition reaction effectively, and optimize nucleation and growth of t ZrO 2 precipitates in c ZrO 2 matrix phase. The materials show transgranular and intergranular fracture characteristics, and exhibit better mechanical properties owing to the cooperative effect of stress induced transformation toughening and microcrack toughening.

关键词： rare earths Mg PSZ ceramic doping Y 2O 3 CeO 2 mechanical property

Bimetallic Ni-Fe catalysts derived from layered double hydroxides for CO methanation from syngas

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Frontiers of Chemical science and Engineering 2017年第4期11卷 613-623页

作者： Tang, Honggui Li, Shuangshuang Gong, Dandan Guan, Yi Liu, Yuan tianjin Univ Sch Chem Engn Dept Catalysis Sci & Technol Tianjin 300072 Peoples R China tianjin Univ Sch Chem Engn Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin 300072 Peoples R China

Carbon deposition and sintering of active components such as nano particles are great challenges for Ni-based catalysts for CO methanation to generate synthetic natural gas from syngas. Facing the challenges, bimetallic catalysts with different Fe content derived from layered double hydroxide containing Ni, Fe, Mg, A1 elements were prepared by co-precipitation method. Nanoparticles of Ni-Fe alloy were supported on mixed oxides of aluminium and magnesium after calcination and reduction. The catalysts were characterized by Brunner- Emmett-Teller （BET）, X-ray diffraction, hydrogen tem- perature programmed reduction, inductively coupled plasma, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric techniques, and their catalytic activity for CO methanation was investigated. The results show that the Ni-Fe alloy catalysts exhibit better catalytic performance than mono- metallic catalysts except for the Ni4Fe-red catalyst. The Ni2Fe-red catalyst shows the highest CO conversion （100% at 260-350 ~C）, as well as the highest CH4 selectivity （over 95% at 280-350 ~C）, owing to the formation of Ni-Fe alloy. In stability test, the Ni2Fe-red catalyst exhibits great improvement in both anti-sintering and resistance to carbon formation compared with the Ni0Fe-red catalyst. The strong interaction between Ni and Fe element in alloy and surface distribution of Fe element not only inhibits the sintering ofnanoparticles but restrains the formation of Ni clusters.

关键词： methanation layered double hydroxide bime-tal Ni-Fe alloy sintering carbon deposition

Phase Development and Crystallization Kinetics of NiTi Prepared by Mechanical Alloying

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Journal of Materials science & technology 2003年第6期19卷 560-562页

作者： Xunyong JIANG, Xueping GAO and Deying SONGinstitute of New Energy Material Chemistry, Nankai University, tianjin 300071, ChinaDepartment of Materials science and Engineering, tianjin institute of technology, tianjin 300191, China inst. of New Energy Mat. Chem. Nankai Univ. Tianjin 300071 China Dept. of Mat. sci. and Eng. Tianjin Inst. of Technol. Tianjin 300191 China

NiTi alloy is produced by mechanical alloying(MA). It becomes amorphous after milling for enough time, such as 100 h in this paper. DSC measurement shows that the crystallization temperature is 676 K for the amorphous powder. Activation energy of crystallization is 199.98 kJ/mol for MA powder, which is lower than that of amorphous prepared by magnetron sputtering. Avrami parameter of crystallization is 1.07.

关键词： NiTi Mechanical alloying Amorphous Crystallization

Laser Surface Remelting of Fe-based Alloy Coating Deposited by APS

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稀有金属材料与工程 2012年第S1期41卷 407-413页

作者： Fu Teng Ye Fuxing Wei Haihong Cui Chong tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China tianjin Key Lab Adv Joining technol Tianjin 300072 Peoples R China

The Fe-based amorphous alloy coatings with different porosities were deposited on Q235 steel substrates by means of atmospheric plasma spraying(APS).The as-sprayed coatings were remelted by the facility of a Nd:YAG laser to further enhance their compactness and bonding strength via orthogonal experiment *** effects of laser remelting on the microstructure,phase compositions and mechanical properties of the as-sprayed coatings were investigated by optical microscopy,scanning electron microscope,X-ray diffraction and Vickers microhardness *** corrosion performance of the coatings was evaluated by both potential dynamic measurements(PDM)and electrochemical impedance spectroscopy(EIS)in a 10%NaOH *** results indicate that laser power of 700 W,scanning velocity of 4 mm/s,beam size of 3 mm and porosity of 1.19%are the optimized remelting process *** laser-remelted coatings exhibite more homogenous structure as strong metallurgical bonding to *** amorphous phases in the as-sprayed coatings crystallize toα-Fe,Fe2Si,Fe3.5B,and Fe2W phases for the high temperature and rapid solidification in the remelting *** microhardness values of as-sprayed are in the range of 700-800 HV0.1,while the microhardness values of the remelted coatings are enhanced slightly to 750-850 *** PDM and EIS analysis results show that the remelted coatings exhibite relatively excellent corrosion resistance compared with the stainless steel 1Cr18Ni9Ti,however the corrosion resistance of the remelted coatings is inferior to the as-sprayed amorphous coatings.

关键词： Fe-based amorphous alloy coating plasma spraying laser surface remelting corrosion resistance

Internal Oxidation of Cu-Al Alloy

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Journal of Materials science & technology 1999年第5期15卷 444-448页

作者： Wu, JJ Zhang, Y Shen, YT Li, GB Lei, TQ Hebei Univ technol Dept Mat Sci & Engn Tianjin 300130 Peoples R China Harbin inst technol Sch Mat Sci & Engn Harbin 150006 Peoples R China

The thermodynamics and kinetics of the internal oxidation in dilute Cu-Al alloy are investigated. The internal oxidation of copper alloy containing 0.2 similar to 1.2 wt pet Al is studied in the temperature range from 1073 K to 1273 K. A related equilibrium diagram is drawn. A mathematic model of oxidation layer depth is developed on the base of the experimental results. The experiments and investigation show that the formation rate of the internal oxidation layer is mainly controlled by the diffusion of O in matrix, the O concentration on the surface and the Al concentration in the alloy.

关键词： Copper alloys