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A Study into Blood Flow, Heart Rate Variability, and Body Surface Temperature While Listening to Music 被引量:1
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作者 Kenichi Itao Makoto Komazawa Hiroyuki Kobayashi 《Health》 2018年第2期181-188,共8页
In this study we examined the relaxing effects of listening to music on a total of 12 women aged from their 20s to their 40s by measuring their blood flow, heart rate variability, and their body surface temperature. A... In this study we examined the relaxing effects of listening to music on a total of 12 women aged from their 20s to their 40s by measuring their blood flow, heart rate variability, and their body surface temperature. As a result, We found that there was a tendency for the volume of blood flow to the fingertips to significantly increase when listening to classical music, but there was a variety of changes in blood flow between each age group for healing music and J-Pop music. When measuring heart rate it was found that the LF/HF value, which is an index for the autonomic nervous system which shows tension and stress, fell significantly when listening to each type of music. Lastly, there was a trend for body surface temperature to rise when listening to classical or healing music, a rise which was particularly significant when listening to healing music. This study shows that a relaxing effect can be expected for all indices when listening to classical music. However, for healing music and J-Pop, personal musical preferences seemed to have an effect and the results were varied. 展开更多
关键词 Music BLOOD flow HEART rate Variability AUTONOMIC Nervous System Body surface TEMPERATURE
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Field Measurements of Influence of Sand Transport Rate on Structure of Wind-sand Flow over Coastal Transverse Ridge 被引量:10
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作者 DONG Yuxiang S L NAMIKAS +1 位作者 P A HESP MA Jun 《Chinese Geographical Science》 SCIE CSCD 2008年第3期255-261,共7页
The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Prov... The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Province, which is one of the most typical coastal aeolian distribution regions in China and famous for the tall and typical coastal transverse ridges. The measurement results show that, on the conditions of approximate wind velocities and same surface materials and environments, some changes happen to the structure of wind-sand flow with the increase of total sand transport rate on the crest of coastal transverse ridge. First, the sand transport rates of layers at different heights in the wind-sand flow increase, with the maximum increase at the height layer of 4-8cm. Second, the ratios of sand trans-port rates of layers at different heights to total sand transport rate decrease at the low height layer (0-4cm), but increase at the high height layer (4-60cm). Third, the distribution of the sand transport rate in the wind-sand flow can be expressed by an exponential function at the height layer of 0-40cm, but it changes from power function model to ex-ponential function model in the whole height layer (0-60cm) and changes into polynomial function model at the height layer of 40-60cm with the increase of total sand transport rate. Those changes have a close relationship with the limit of sand grain size of wind flow transporting and composition of sand grain size in the wind-sand flow. 展开更多
关键词 sand transport rate coastal transverse ridge structure of wind-sand flow field measurement
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Methodology for production logging in oil-in-water flows under low flow rate and high water-cut conditions 被引量:2
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作者 Wang Da-Yang Jin Ning-De +2 位作者 Zhai Lu-Sheng Ren Ying-Yu He Yuan-Sheng 《Applied Geophysics》 SCIE CSCD 2019年第3期302-313,395,共13页
This study aimed to obtain the production profiles of oil-in-water flow under low flow rate and high water-cut conditions in oil wells.A combination production profile logging composed of an arc-type conductance senso... This study aimed to obtain the production profiles of oil-in-water flow under low flow rate and high water-cut conditions in oil wells.A combination production profile logging composed of an arc-type conductance sensor(ATCS)and a cross-correlation flow meter(CFM)with a center body is proposed and experimentally evaluated.The ATCS is designed for water holdup measurement,whereas the CFM with a center body is proposed to obtain the mixture velocity.Then,a drift-flux model based on flow patterns is established to predict the individual-phase superficial velocity of oil-in-water flows.Results show that the ATCS possesses high resolution in water holdup measurement and that flow pattern information can be deduced from its signal through nonlinear time series analysis.The CFM can enhance the correlation of upstream and downstream signals and simplify the relationship between the cross-correlation velocity and mixture velocity.On the basis of the drift-flux model,individual-phase superficial velocities can be predicted with high accuracy for different flow patterns. 展开更多
关键词 oil-in-water flows low flow rate high water-cut conductance sensor flow meter measurement model
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Partial phase flow rate measurements for stratified oil-water flow in horizontal wells 被引量:1
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作者 SONG Hongwei GUO Haimin +1 位作者 GUO Shuai SHI Hangyu 《Petroleum Exploration and Development》 2020年第3期613-622,共10页
To accurately measure and evaluate the oil-water production profile of horizontal wells, a dynamic measurement experiment of oil-water two-phase flow in horizontal wells and numerical simulation were combined to estab... To accurately measure and evaluate the oil-water production profile of horizontal wells, a dynamic measurement experiment of oil-water two-phase flow in horizontal wells and numerical simulation were combined to establish a method for measuring the partial phase flow rate of oil-water two-phase stratified flow in horizontal wells. An experimental work was performed in horizontal oil-water two-phase flow simulation well using combination production logging tool including mini-capacitance sensor and mini-spinner. The combination tool provides a recording of holdup and velocity profiles at five different heights of the borehole cross-section. The effect of total flow rate and water-cut on the response of spinner and capacitive sensor at five measured positions were investigated. The capacitance water holdup interpolation imaging algorithm was used to determine the local fluid property and oil-water interface height, and the measured local fluid speed was combined with the numerical simulation result to establish an optimal calculation model for obtaining the partial phase flow rate of the oil-water two-phase stratified flow in the horizontal well. The calculated flow rates of five measured points are basically consistent with the experimental data, the total flow rate and water holdup from calculation are in agreement with the set values in the experiment too, suggesting that the method has high accuracy. 展开更多
关键词 horizontal well oil-water two-phase flow stratified flow regime flow rate measurement fluid dynamics experiment production logging
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A New Method for Measurement of Helium Mass Flow Rate in the Cryogenic System of TORE SUPRA
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作者 欧阳峥嵘 Pascal Reynaud 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2825-2827,共3页
The TORE SUPRA Tokamak was built by EURATOM-CEA association. The NbTi conductor of superconducting coils is inserted in a tight enclosure filled with pressurized superfluid helium of 0.125 MPa at 1.8 K. The thick casi... The TORE SUPRA Tokamak was built by EURATOM-CEA association. The NbTi conductor of superconducting coils is inserted in a tight enclosure filled with pressurized superfluid helium of 0.125 MPa at 1.8 K. The thick casing is cooled to 4.5 K by 1.8 MPa in 4.5 K supercritical helium circulation. Around this thick casing, a 80 K thermal shield protects the parts at very low temperatures from the thermal radiation, which is cooled by pressurized helium at 80 K and 1.8 MPa. A new measurement method for helium mass flow rate of 80 K shield and 4.5 K casing is described in this paper. The commissioning was done on the two helium loops of the cryoplant: the supercritical 4.5 K thick casing and 80 K shields. The purpose is to improve control of the 4.5 K and 80 K refrigeration loops. 展开更多
关键词 mass flow rate VALVE MEASUREMENT HELIUM
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Re-measuring International Short-term Capital Flow into China with Varying Methods
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作者 张明 《China Economist》 2011年第5期80-92,共13页
This paper.fi'rst conducts a systematic review of domestic and foreign scholars' approaches to predicting short-term capital flows, then employs a combination of both direct and indirect methods to carry out its ana... This paper.fi'rst conducts a systematic review of domestic and foreign scholars' approaches to predicting short-term capital flows, then employs a combination of both direct and indirect methods to carry out its analysis. Three kinds of indicators, both specific and general, are applied in both methods. Thorough consideration is given to short-term international capital inflow from trade, other current account items, capital account, and errors and omissions, as well as other channels through which short term capital might accrue to a nation's balance. Based on a comprehensive comparison of year-on-year data, this paper also estimates monthly data using a simplified, indirect calculation approach. Estimates show that, despite a degree of difference in results between methods, most estimates are highly consistent for a given period. Based on monthly estimates, we conclude that turbulence in international financial markets (i.e., the United States subprime mortgage crisis and the European sovereign debt crisis) has had a major impact on China 's short-term capital flow. 展开更多
关键词 short-term international capital flows direct method indirect method scale measurement
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Experimental study on preferential solution flow during dump leaching of low-grade ores 被引量:3
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作者 尹升华 吴爱祥 +1 位作者 苏永定 张杰 《Journal of Central South University of Technology》 EI 2007年第4期584-588,共5页
The phenomenon of preferential solution flow during dump leaching of low-grade ores was studied.The formative mechanism of preferential solution flow was investigated through analyzing the relationship between permeab... The phenomenon of preferential solution flow during dump leaching of low-grade ores was studied.The formative mechanism of preferential solution flow was investigated through analyzing the relationship between permeability and ore diameter,and the relationship between surface tension and ore diameter.The preferential solution flow happened within the fine ore area when the dump was unsaturated.And it could happen within the coarse ore area when the dump became saturated.The results of experiment show that the outflow of coarse ore area increases sharply with higher applied rate.The outflow of fine ore area is greater than that of coarse ore area when the applied rate is below 3.2 L/min,and the preferential solution flow happens in fine ore area.But the preferential solution flow happens in coarse ore area when the applied rate is higher than 3.2 L/min.The result of the experiment is consistent with the mechanism analyzing. 展开更多
关键词 low-grade ore preferential solution flow PERMEABILITY surface tension applied rate
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FlowLevelCon油气井动液面连续监测系统的研制及应用 被引量:1
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作者 毛军军 杨若谷 +3 位作者 魏方方 任桂山 苏锋 米立飞 《数码设计》 2017年第6期216-218,共3页
在油田的开发以及采油过程中,动液面是一个非常重要的参数。动液面值的测量对掌握油井生产工况和调整生产参数均十分关键,为及时准确地测量油井液面深度,研制了一套FlowLevelCon油气井动液面连续监测系统;本文介绍了该系统的测量原理、... 在油田的开发以及采油过程中,动液面是一个非常重要的参数。动液面值的测量对掌握油井生产工况和调整生产参数均十分关键,为及时准确地测量油井液面深度,研制了一套FlowLevelCon油气井动液面连续监测系统;本文介绍了该系统的测量原理、软硬件实现过程及现场应用情况。通过该系统在大港油田对不同工况油井的试验效果表明,单井动液面计量误差在1.0%以内,满足油田现场计量需求。 展开更多
关键词 油井动液面 flowLevelCon 回声法 在线计量
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Possibility of a Straightening Flow-Meter by Using Woven Screen
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作者 Takahiro Tsuchiya Yota Koishi +1 位作者 Mitsuo Iwamoto Hidemi Yamada 《Open Journal of Fluid Dynamics》 2015年第1期34-38,共5页
In this paper, the possibility of the flow rate measurement for a circular pipe flow by using a wo-ven screen with the property of straightening un-uniform flows is discussed. The resistance coefficient and the flow r... In this paper, the possibility of the flow rate measurement for a circular pipe flow by using a wo-ven screen with the property of straightening un-uniform flows is discussed. The resistance coefficient and the flow rate coefficient are estimated from the pressure difference caused by the woven screen under the experiment ranges of the wire Reynolds number, Red = 2.2 × 102-1.8 × 103, and of the open area ratio, β = 0.28-0.65. As a result, the resistance coefficient decreases and the flow rate coefficient increases as the wire Reynolds number Red or the open area ratio β increases. In addition, both coefficients are not affected by the difference between uniform and turbulent pipe flows approaching the woven screen. Therefore, the possibility of a flow-meter having the property to straighten the un-uniform flow is expected. 展开更多
关键词 flow rate Measurement Woven SCREEN flow-Straightening Resistance COEFFICIENT
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THE CLINICAL SIGNIFICANCE OF FLOW CYTOMETRIC DEOXYRIBONUCLEIC ACID MEASUREMENT OF DEPARA-FFINIZED SPECIMEN IN BLADDER TUMOR
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作者 王泽 缪廷杰 +1 位作者 熊汝成 曹世龙 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第1期77-81,共5页
A retrospective study of flow cytometric measurements on paraffin-embedded tumor specimens from 188 patients with bladder tumor was conducted. The results were analyzed in combination with the morphological variation ... A retrospective study of flow cytometric measurements on paraffin-embedded tumor specimens from 188 patients with bladder tumor was conducted. The results were analyzed in combination with the morphological variation of bladder tumors. It was found that the DNA ploid pottern, degree of infiltration and the multiplicity of bladder tumor were closely related with tumor recurrence, among which the DNA ploid pattern was most significant. In aneuploid bladder tumors the recurrent rate and mean annual recurrence frequency were 76.7% and 1.46, and those in the diploid bladder tumors were 18.7% and 0.33 respectively. Aneuploid was the most indicative parameter of the recurrence in bladder tumors. In addition, according to the DNA ploid pattern and DNA index (DI), the aneuploid tumors in our group were divided into 4 types, namely, tetraploid tumors, npn-euploid with DI(?)1.5, non-euploid tumors with DI>1.5 and two-aneuploid tumors. The results showed that the recurrent rate of tetraploid tumors was relatively lower and it became higher and higher in the following order: non-euploid tumors with DI(?)1.5, non-euploid tumors with DI>1.5, and two-aneuploid tumors. This indicates that there are different biological behaviors in tumors with different ploid pattern. Finally, the correlation between DNA ploid pattern and tumor metastasis was also discussed. 展开更多
关键词 rate THE CLINICAL SIGNIFICANCE OF flow CYTOMETRIC DEOXYRIBONUCLEIC ACID MEASUREMENT OF DEPARA-FFINIZED SPECIMEN IN BLADDER TUMOR DNA FCM
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Experiment on Vaporization of Jet into Cross-Flow
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作者 MA Cuuxiang DENG Yucnhao +1 位作者 YAN Yingwen XU Huasheng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第6期977-985,共9页
The injection characteristics of the main fuel nozzle,which is widely applied in advanced lean-premixed-prevaporized(LPP)low-emission combustors,can be simplified as the atomization and vaporization processes of a jet... The injection characteristics of the main fuel nozzle,which is widely applied in advanced lean-premixed-prevaporized(LPP)low-emission combustors,can be simplified as the atomization and vaporization processes of a jet into cross-flow.In this study,a nozzle with a diameter of 0.4 mm is designed and processed through the heating of the inlet air,and the vaporization characteristics are investigated.The optical measurement and cyclone separation methods are separately used to investigate the evaporation rate of a jet into cross-flow.Experimental results show that the fuel evaporation rate in cross-flow is mainly affected by the Weber number(We),equivalent ratio(φ),momentum rate of fuel to air(q),and air temperature.In addition,the inlet temperature is a crucial factor for the evaporation ratio of a jet into cross-flow.The evaporation results measured by two different methods in the same cross-flow are very close to each other with a deviation within 10%. 展开更多
关键词 evaporation rate JET CROSS-flow optical measurement cyclone separation method
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Improvements to machining surface quality by controlling the flow direction of electrolyte during electrochemical sinking and milling of titanium alloy 被引量:4
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作者 LIU Yang QU NingSong 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2020年第12期2698-2708,共11页
Electrochemical milling is eminently suitable for machining aerospace parts(which usually have complex structures) because of its great flexibility. However,titanium alloys are particularly sensitive to changes in the... Electrochemical milling is eminently suitable for machining aerospace parts(which usually have complex structures) because of its great flexibility. However,titanium alloys are particularly sensitive to changes in the flow field,which often cause severe pitting corrosion of the machined surface. Although electrochemical sinking and milling(ESM) can restrict the flow of electrolyte and reduce pitting corrosion,the quality of the machined surface is not ideal because the latter are susceptible to stray corrosion. To reduce such corrosion and improve the surface quality,the internal flow channel of the tool electrode and the cutting depth were investigated thoroughly. Extensive experiments revealed that stray corrosion could be reduced significantly and surface quality improved by controlling the electrolyte flow direction in the machining area,which was achieved by changing the style of the internal flow channel of the tool electrode. These reductions in corrosion and surface roughness were achieved using a tool electrode with a triangular internal flow channel. In addition,the main components and micro-hardness of the machined surface were close to that of the TB6 titanium alloy substrate,which helped to maintain the inherent high strength of the titanium alloy. The surface of the workpiece changed from being hydrophilic to being hydrophobic,which reduced the flow resistance. 展开更多
关键词 electrochemical sinking and milling titanium alloys flow direction surface quality and characteristics
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Modeling and Analysis of A Rotary Direct Drive Servovalve 被引量:12
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作者 YU Jue ZHUANG Jian YU Dehong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第5期1064-1074,共11页
Direct drive servovalves are mostly restricted to low flow rate and low bandwidth applications due to the considerable flow forces.Current studies mainly focus on enhancing the driving force,which in turn is limited t... Direct drive servovalves are mostly restricted to low flow rate and low bandwidth applications due to the considerable flow forces.Current studies mainly focus on enhancing the driving force,which in turn is limited to the development of the magnetic material.Aiming at reducing the flow forces,a novel rotary direct drive servovalve(RDDV)is introduced in this paper.This RDDV servovalve is designed in a rotating structure and its axially symmetric spool rotates within a certain angle range in the valve chamber.The servovalve orifices are formed by the matching between the square wave shaped land on the spool and the rectangular ports on the sleeve.In order to study the RDDV servovalve performance,flow rate model and mechanical model are established,wherein flow rates and flow induced torques at different spool rotation angles or spool radiuses are obtained.The model analysis shows that the driving torque can be alleviated due to the proposed valve structure.Computational fluid dynamics(CFD)analysis using ANSYS/FLUENT is applied to evaluate and validate the theoretical analysis.In addition,experiments on the flow rate and the mechanical characteristic of the RDDV servovalve are carried out.Both simulation and experimental results conform to the results of the theoretical model analysis,which proves that this novel and innovative structure for direct drive servovalves can reduce the flow force on the spool and improve valve frequency response characteristics.This research proposes a novel rotary direct drive servovalve,which can reduce the flow forces effectively. 展开更多
关键词 direct drive servovalve computational fluid dynamics(CFD) flow rate flow induced torque
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YIELD SURFACES AND PLASTIC FLOW OF 45 STEEL UNDER TENSION-TORSION LOADING PATHS 被引量:5
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作者 Guijuan Hu Keshi Zhang +1 位作者 Shihong Huang Jiann-Wen Woody Ju 《Acta Mechanica Solida Sinica》 SCIE EI 2012年第4期348-360,共13页
An experimental analysis on the subsequent yield-surfaces evolution using multiple specimens is presented for a 45 steel after a prescribed pre-strain loading in three different directions respectively, and the yieldi... An experimental analysis on the subsequent yield-surfaces evolution using multiple specimens is presented for a 45 steel after a prescribed pre-strain loading in three different directions respectively, and the yielding is defined by a designated offsetting strain. The size of the subsequent yield surface is found smaller than the initial yield surface; the negative cross effects are observed in the normal loading direction, its shape is not a Mises circle but has a rather blunt nose in loading direction and flat in the opposite. These results strongly depend on the loading path and the prescribed offset plastic strain. The plastic flow direction to the subsequent yield surface is investigated, and it is found that the plastic flow direction deviates from the normal flow rule. The deviation differs from preloading case to preloading case. And the plastic flow direction would have a larger deviation from the normal of the yield surface, if the subsequent yield was defined by a smaller offset strain. Furthermore, the experiments are simulated using the Chaboche model, and the results show that it can rationally predict yield-surface only when yield is defined by a fairly large offset strain. 展开更多
关键词 subsequent yield surface plastic flow direction multiple specimen methods offsetstrain
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Reaction kinetics of fluorite in flow systems and surface chemistry 被引量:7
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作者 张荣华 胡书敏 《Science China Earth Sciences》 SCIE EI CAS 1996年第6期561-575,共15页
The kinetic experiments of fluorite in water-HCl solution in an open-flow system at the temperatures ≤100℃ reveal that the variation of flow rate (U) can change the reaction rate orders from 0 to 2 or higher. In the... The kinetic experiments of fluorite in water-HCl solution in an open-flow system at the temperatures ≤100℃ reveal that the variation of flow rate (U) can change the reaction rate orders from 0 to 2 or higher. In the far from equilibrium systems, the dissolution rates of fluorite in aqueous solutions have a zero order.The reaction rates are controlled by pH values of input solutions. In fact, the reaction rates are related to the concentrations of the active sites occupied by H+ on fluorite surface [SOH]. X-ray photospectroscopy observations on fluorite surface before and after reaction indicate that surface chemical processes control the reaction rates: Cl- cations attach on and enter into surface of fluorite besides H+ when fluorites react with HCl solutions, which affect the reaction rates. 展开更多
关键词 open-flow system REACTION rates surface chemistry.
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Catalyst-Free Growth of Graphene by Microwave Surface Wave Plasma Chemical Vapor Deposition at Low Temperature 被引量:2
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作者 Sudip Adhikari Hare Ram Aryal +1 位作者 Hideo Uchida Masayoshi Umeno 《Journal of Materials Science and Chemical Engineering》 2016年第3期10-14,共5页
Catalyst-free graphene films has been synthesized by microwave (MW) surface wave plasma (SWP) chemical vapor deposition (CVD) using hydrogenated carbon source on silicon substrates at low temperature (500℃). The synt... Catalyst-free graphene films has been synthesized by microwave (MW) surface wave plasma (SWP) chemical vapor deposition (CVD) using hydrogenated carbon source on silicon substrates at low temperature (500℃). The synthesized process is simple, low-cost and possible for application on transparent electrodes, gas sensors and thin film resistors. Analytical methods such as Raman spectroscopy, transmission electron microscopy (TEM) and four points prove resistivity measurement and UV-VIS-NIR spectroscopy were employed to characterize properties of the graphene films. The formation of multilayer of graphene on silicon substrate was confirmed by Raman spectroscopy and TEM. It is possible to grow graphene directly on silicon substrate (without using catalyst) due to high radical density of MW SWP CVD. In addition, we also observed that the hydrogen had significant role for quality of graphene. 展开更多
关键词 Graphene Films Direct Synthesis H2 flow rate Silicon Substrate Microwave surface Wave Plasma CVD
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双封隔取样压力数据深入解释方法研究
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作者 余强 褚晓冬 +3 位作者 周艳敏 秦小飞 孔笋 左有祥 《测井技术》 CAS 2024年第4期558-564,共7页
双封隔器是一种地层测试测压取样工具,取样过程通常需要泵抽几小时甚至十几小时,取得地层流体样品,获得压力和流量数据,但无法真实反映地层渗透率的探测范围。利用油藏模拟软件模拟双封隔器泵抽取样过程,引入Schroeter算法和Levitan算... 双封隔器是一种地层测试测压取样工具,取样过程通常需要泵抽几小时甚至十几小时,取得地层流体样品,获得压力和流量数据,但无法真实反映地层渗透率的探测范围。利用油藏模拟软件模拟双封隔器泵抽取样过程,引入Schroeter算法和Levitan算法这两种压力/流量数据反褶积算法,反演渗透率参数波及半径从几厘米到上百米,并使用数值模拟案例验证了只利用取样完成后的压力恢复数据进行反褶积方法的准确性和合理性。该研究应用于双封隔现场测井数据,采用反褶积方法得到渗透率探测半径31m,反褶积处理后的数据可用于产能预测,对正确认识油气藏具有重要意义。 展开更多
关键词 双封隔器 压力/流量反褶积 模型反演 测压解释 地层测试
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进液量对气举式同向出流旋流器分离特性影响
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作者 刘彩玉 郑九洲 +1 位作者 李枫 张勇 《机械设计与制造》 北大核心 2024年第2期165-169,共5页
为了提高旋流器的分离效率,提出一种气举式同向出流水力旋流器结构,通过注气的方式将旋流器轴心的油核举升至溢流口,加速油核向溢流口方向运动,进而提升旋流器的分离性能。基于雷诺应力模型(Reynolds Stress Model,RSM)与多相流模型(Mix... 为了提高旋流器的分离效率,提出一种气举式同向出流水力旋流器结构,通过注气的方式将旋流器轴心的油核举升至溢流口,加速油核向溢流口方向运动,进而提升旋流器的分离性能。基于雷诺应力模型(Reynolds Stress Model,RSM)与多相流模型(Mixture),模拟计算了入口进液量对气举式同向出流旋流器分离性能的影响,分析了进液量对旋流器内气核形态、速度场分布以及分离性能的影响规律。数值模拟结果表明:进液量分布在(3.6~8.4)m^(3)/h范围内时,随着进液量的增加,注气口处压力逐渐增大,混合液内各相介质的轴向速度与径向速度均有显著提高,旋流器轴心处的油相体积分数明显增大,旋流器的分离效率从64%增至77.9%。 展开更多
关键词 进液量 旋流器 同向出流 数值模拟 分离效率
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基于居里面深度对中国东北部大地热流的研究
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作者 邱楠生 许晴 +2 位作者 朱传庆 宋佳霖 李潇 《地质学报》 EI CAS CSCD 北大核心 2024年第3期680-691,共12页
大地热流值是表征地球热状态的重要参数,也是进行深部地温预测和评价一个地区地热资源的最基本数据。受钻孔测温的影响,盆地外的无钻孔测温地区缺少实测的大地热流值。目前的热流分布图都是依据相邻盆地的实测值进行插值绘制的,无钻孔... 大地热流值是表征地球热状态的重要参数,也是进行深部地温预测和评价一个地区地热资源的最基本数据。受钻孔测温的影响,盆地外的无钻孔测温地区缺少实测的大地热流值。目前的热流分布图都是依据相邻盆地的实测值进行插值绘制的,无钻孔区热流值可信度较低。由于岩石居里点与温度密切相关,可以通过居里面深度来研究地表热流值。本文依据东北地区现有的居里面深度分布图,结合实测的岩石热导率、岩石生热率数据和相应的地壳分层状况,计算了东北地区的大地热流值,重新绘制了中国东北地区精细的大地热流分布图。东北地区整体大地热流处于42.5~95 mW/m~2之间,热流高值位于五大连池及敦化-密山断裂带海龙—牡丹江一带,松辽盆地内部、小兴安岭和长春-延吉缝合带也有局部的高热流值。热流高值与居里面隆起区域有较高的一致性,即居里面隆起处热流较高,而坳陷区热流较低。本次研究填补了中国东部地区热流实测值空白,为该区深部地温预测和地热资源评价提供了更加准确的参数。 展开更多
关键词 居里面 大地热流 岩石热导率 岩石生热率 地热资源
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高精度管道漏风量测试仪的设计及实验研究
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作者 张白 曹威 +2 位作者 蒋尊阳 孔德超 王胜南 《机电工程》 CAS 北大核心 2024年第10期1784-1792,1805,共10页
现有的国产漏风量测试仪普遍存在测量精度低、自动化水平低的问题,为此,基于漏风量测试仪的原理,开展了漏风量测试仪的结构设计、系统设计及整机实验研究。首先,对漏风量的测量过程、喷嘴流量测量原理进行了研究,推导了喷嘴流量测量公式... 现有的国产漏风量测试仪普遍存在测量精度低、自动化水平低的问题,为此,基于漏风量测试仪的原理,开展了漏风量测试仪的结构设计、系统设计及整机实验研究。首先,对漏风量的测量过程、喷嘴流量测量原理进行了研究,推导了喷嘴流量测量公式,并根据相关标准设计了角接取压方式的喷嘴结构,基于仪器操作便捷性要求,对整机结构进行了设计;其次,采用空气密度补偿公式完成了高精度流量自适应测量,设计了基于自锁式电磁阀的换向调零电路,采用换向调零法对压差传感器零点漂移进行了补偿,使用小波阈值去噪算法消除了信号噪声,提高了流量的测量精度;采用抗积分饱和比例积分微分(PID)算法对流量进行了闭环控制;最后,研制了管道漏风量测试仪样机,开展了压差与流量测量精度与重复性实验。实验及研究结果表明:该高精度漏风量测试仪工作状态稳定,压差测量精度为±0.4%,流量测量精度为±2%;该漏风量测试仪的测量精度优于国内同类仪器,符合国家标准要求,具有良好的市场前景。 展开更多
关键词 漏风量测试仪表 喷嘴流量 换向调零法 小波阈值去噪算法 压差测量精度 比例-积分-微分
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