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Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

作者： Gu-jun Chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

Effect of Short Chain Alcohols upon Viscosity of TTAB Solution

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Chinese Journal of Chemical Physics 2008年第2期21卷 169-173页

作者： Yun-fei Yan Hua-zhen Li Hai-yang Yang Jia-sheng Qian ping-ping Zhu ping-sheng He Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China

The effect of ethanol （C2H5OH）, propanol （C3H7OH）, and butanol （C4H9OH） upon the viscosity of tetradecyltrimethylammonium bromide （TTAB） solution in the presence or absence of KBr at 30℃was investigated, where the surfactant concentration CS is kept constant. In the absence of KBr, the relative viscosity ηr of TTAB solution increases linearly with the alcohol concentration CA, indicating that the alcohols do not promote micelle formation of TTAB. In the presence of KBr, ηr linearly decreases with CA for C2H5OH, but it exhibits a maximum with increasing CA for C3H7OH or C4H9OH. The facts reveal that C2H5OH or C4H9OH promotes the micelle formation of TTAB. A possible explanation is that the hydrophobicity of the mieellar interior is enhanced by KBr, so that C2H5OH or C4H9OH can dissolve in micelle and promotes micelle formation. In the presence of KCl, which is less efficient in promoting the micelle formation of cationic surfactant, both C3H7OH and C4H9OH have only a slight effect on the micelle formation. In contrast, due to the hydrophilicity, C2H5OH cannot dissolve in micelles in the presence of KBr or KCl.

关键词： Relative viscosity Cationic surfactant Organic additive Hydrophobic interaction

Study of Pseudogap in Underdoped Cuprate

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Communications in Theoretical Physics 2001年第7期36卷 91-94页

作者： LOU ping WU Hang-sheng Department of Physics Anhui University Hefei 230039 China Department of Physics University of Science and Technology of China Hefei 230026 China

A mean-field spin-density wave (SDW) analysis of pseudogap in the underdoped cuprates is proposed on the dependence of the energy gap which mimics the pseudogap near (π, 0) point at least. It implies that the pseudogap structure near (π, 0) is not sensitive to the long-range order and will survive leading to the pseudogap phenomenon in the underdoped metallic phase. On the other hand, in the long-range ordering antiferromagnetic region, the mean-field SDW theory holds and the pseudogap structure predicated by the theory should be observable experimentallyv. Then one prediction is that the pseudogap would smoothly extrapolate between itinerant antiferromagnetic phase and underdoped metallic phase.

关键词： high-temperature superconductors, pseudogap, underdoped cuprates, mean-field SDW analysis

EFFECTS OF NH_4Cl ON THE INTERACTION BETWEEN POLY(ETHYLENE OXIDE) AND IONIC SURFACTANTS IN AQUEOUS SOLUTIONS

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Chinese Journal of Polymer Science 2008年第1期26卷 31-37页

作者： Li, Jing Li, Hua-zhen Yang, Hai-yang Zhu, ping-ping He, ping-sheng Univ Sci & Technol China Dept Polymer Sci & Engn Hefei 230026 Peoples R China

The interaction of poly(ethylene oxide)(PEO)with the ionic surfactants,sodium dodecylsulfate(SDS)and cetyltrimethylammonium chloride(CTAC)respectively,in aqueous solutions containing a certain concentration of NH_4Cl, is studied by the viscosity *** has been found that the ion-dipole interaction between PEO and ionic surfactants is changed considerably by the organic *** anionic suffactant of SDS,the addition of NH_4Cl into solution strengthens the interaction between PEO and the headgroup o...

关键词： Viscosity Ion-dipole interaction Non-ionic polymer Ionic surfactant NH_4Cl

A Rescheduling Method for Operation Time Delay Disturbance in Steelmaking and Continuous Casting Production Process

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Journal of Iron and Steel Research International 2012年第12期19卷 33-41页

作者： YU sheng-ping PAN Quan-ke State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819 Liaoning China

In the steelmaking and continuous casting （SMCC） production process, operation time delay may lead to casting break or processing conflict so that the initial scheduling plan becomes unrealizable. Existing research meth- ods are difficult to guarantee the accuracy of the model and successful application to actual applications. The resched- uling problem in response to operation time delay is firstly analyzed. This is then followed by the establishment of a novel multi-obiective nonlinear programming model （MONPM）. In specifications, a three-stage rescheduling method is proposed including the batches splitting （BS）, forward scheduling method （FSM） and backward scheduling meth- od （BSM）. As a result, the real-time application shows that the proposed rescheduling method efficiently ensures the continuous casting and dramatically shortens the redundant waiting time for molten steel in very short rescheduling time.

关键词： SMCC rescheduling disturbance heuristic algorithm

Methods for seismic sedimentology research on continental basins

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Petroleum Science 2015年第1期12卷 67-80页

作者： ping-sheng Wei Ming-Jun Su Petrochina Research Institute of Petroleum Exploration & Development-Northwest

In contrast to marine deposits, continental deposits in China are characterized by diverse sedimentary types, rapid changes in sedimentary facies, complex lithology, and thin, small sand bodies. In seismic sedimentology studies on continental lacustrine basins, new thinking and more detailed and effective technical means are needed to generate lithological data cubes and conduct seismic geo- morphologic analyses. Based on a series of tests and studies, this paper presents the concepts of time-equivalent seismic attributes and seismic sedimentary bodies and a ＂four-step approach＂ for the seismic sedimentologic study of conti- nental basins： Step 1, build a time-equivalent stratigraphic framework based on vertical analysis and horizontal corre- lation of lithofacies, electrofacies, seismic facies, and pale- ontological combinations; Step 2, further build a sedimentary facies model based on the analysis of single- well facies with outcrop, coring, and lab test data; Step 3, convert the seismic data into a lithological data cube reflecting different lithologies by means of seismic tech- niques; and Step 4, perform a time-equivalent attribute analysis and convert the planar attribute into a sedimentary facies map under the guidance of the sedimentary facies model. The whole process, highlighting the verification and calibration of geological data, is an iteration and feedback procedure of geoseismic data. The key technologies include the following：（1） a seismic data-lithology conversion technique applicable to complex lithology, which can convert the seismic reflection from interface types to rock layers; and （2） time-equivalent seismic unit analysis and a time- equivalent seismic attribute extraction technique. Finally, this paper demonstrates the validity of the approach with an example from the Qikou Sag in the Bohai Bay Basin and subsequent drilling results.

关键词： Continental basin Seismic sedimentology Four-step approach Time-equivalent seismic attribute Seismic sedimentary body Lithology conversion processing

Potential Connection between the Australian Summer Monsoon Circulation and Summer Precipitation over Central China

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Atmospheric and Oceanic Science Letters 2015年第3期8卷 120-126页

作者： HE sheng-ping Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences

This study investigated the connection between the Australian summer monsoon(ASM) and summer precipitation over central China. It was found that,following a weaker-than-normal ASM, the East Asian summer monsoon and western North Pacific subtropical high tend to be stronger, yielding anomalous northward moisture to be transported from the western Pacific to central China. Besides, anomalous upwelling motion emerges over 30–37.5°N, along 110°E. Consequently,significant positive summer precipitation anomalies are located over central China. Further analysis indicated that the boreal winter sea surface temperature(SST) in the Indian Ocean and South China Sea shows positive anomalies in association with a weaker-than-normal ASM. The Indian Ocean warming in boreal winter could persist into the following summer because of its own long memory, emanating a baroclinic Kelvin wave into the Pacific that triggers suppressed convection and an anomalous anticyclone. Besides, the abnormal SST signal in the South China Sea develops eastward with time because of local air-sea interaction, causing summer SST warming in the western Pacific. The SST warming can further affect East Asian atmospheric circulation and precipitation through its impact on convection.

关键词： Australian summer monsoon East Asian summer monsoon precipitation

Asymmetry in the Arctic Oscillation Teleconnection with January Cold Extremes in Northeast China

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Atmospheric and Oceanic Science Letters 2015年第6期8卷 386-391页

作者： HE sheng-ping Climate Change Research Center Chinese Academy of Sciences Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences

The connection of the Arctic Oscillation(AO)with the frequency of temperature extremes over East Asia during boreal winter has been documented by many *** study describes an asymmetry in the relationship between the January AO and the simultaneous cold extremes in Northeast China(NEC),and further reveals a breakdown of this *** is demonstrated that the frequency of January cold extremes in NEC shows significant(insignificant)negative correlation with the simultaneous negative(positive)phase of the *** possible explanation for such an asymmetry is that the Arctic center of negative AO extends more southwards to Siberia compared with that of positive AO,conducive to a closer connection with the frequency of an extreme Siberian *** a result,the frequency of January cold extremes in NEC shows a more significant relationship with the negative *** other related explanation is that,concurrent with the negative phase of the AO,there is an evident meridional stationary planetary wave in the upper troposphere around(30°N,100–300 hP a),which disappears in the positive ***,the negative AO could better reflect the fluctuation of the subtropical westerly wind and the synoptic-scale transient wave activity,which is closely related to the frequency of cold extremes in *** with a positive polarity of the AO trend since the mid-1980s,the connection between the cold extremes over NEC and the AO during January has been weakened.

关键词： Arctic Oscillation temperature extremes asymmetry