This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity...This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity field of the sensor in a pipe with 20 mm inner diameter and the effect of sensor geometry on the distribution of sensitivity field is presented. Then, a horizontal oil–water two-phase flow experiment is carried out to measure the response of the double helix capacitance sensor, in which a novel method is proposed to calibrate the liquid holdup based on three pairs of parallel-wire capacitance probes. The performance of the sensor is analyzed in terms of the flow structures detected by mini-conductance array probes.展开更多
To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overc...To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overcomes the influence of the pipe wall. The data collection system is improved by using high performance IC (integrated circuit). Static tests of bubble flow, stratified flow and annular flow regime are carried out. Measurements are taken on bubble flow, stratified flow and slug flow. Results show that the new ECT system performs well on void fraction measurement of bubble flow and stratified flow, but the error of measurement for slug flow is more than 10%.展开更多
The working principle of the pipeline intelligent pig and the structure of ultrasonic probe array used to detect defects in oil/gas pipeline are introduced. The effects of the array＇ s radial position in pipe on defe...The working principle of the pipeline intelligent pig and the structure of ultrasonic probe array used to detect defects in oil/gas pipeline are introduced. The effects of the array＇ s radial position in pipe on defect resolution are analyzed. The causes leading to radial positioning error are investigated. An algo- rithm for the radial self-positioning is presented. The experimental results show that the radial self-positioning algorithm can eliminate the array＇ s space position error effectively and improve the defect resolution.展开更多
This paper presents the possibilities offered by fluorescence spectroscopy for the identification of vegetable oils such as soybean, sunflower, flax, walnut, corn, almond, sesame, olive and pumpkin oils. The probes un...This paper presents the possibilities offered by fluorescence spectroscopy for the identification of vegetable oils such as soybean, sunflower, flax, walnut, corn, almond, sesame, olive and pumpkin oils. The probes under study have been excited with two types of sources： a laser diode （LD） and light-emitting diodes （LEDs） emitting in the UV and in the visible range. Total luminescence spectra were recorded by measuring the emission spectra in the range 350-720 nm at excitation wavelengths from 375 to 450 nm. The excitation-emission matrices have been obtained and two basic fluorescence regions in the visible have been outlined. On this basis the fluorescence spectra of the oils have been subdivided into three categories depending on the prevalence of the fluorescence maxima. The samples show differences in their fluorescence spectra. The latter fact shows that fluorescence spectroscopy can be used for the quick identification of edible oils. The fatty acid, the tocopherol, the beta-carotene and chlorophyll contents in the analyzed oils have been studied. It is shown that some of the types of oils differ significantly from each other by the first derivatives of their fluorescence spectra. There also exist color differences between the groups of vegetable oils under study.展开更多
Understanding the holistic relationship between refinery production scheduling(RPS) and the cyber-physical production environment with smart scheduling is a new question posed in the study of process systems engineeri...Understanding the holistic relationship between refinery production scheduling(RPS) and the cyber-physical production environment with smart scheduling is a new question posed in the study of process systems engineering. Here, we discuss state-of-the-art RSPs in the crude-oil refining field and present examples that illustrate how smart scheduling can impact operations in the high-performing chemical process industry. We conclude that, more than any traditional off-the-shelf RPS solution available today, flexible and integrative specialized modeling platforms will be increasingly necessary to perform decentralized and collaborative optimizations,since they are the technological alternatives closer to the advanced manufacturing philosophy.展开更多
基金Supported by the National Natural Science Foundation of China(50974095,41174109,61104148)the National Science and Technology Major Projects(2011ZX05020-006)
文摘This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity field of the sensor in a pipe with 20 mm inner diameter and the effect of sensor geometry on the distribution of sensitivity field is presented. Then, a horizontal oil–water two-phase flow experiment is carried out to measure the response of the double helix capacitance sensor, in which a novel method is proposed to calibrate the liquid holdup based on three pairs of parallel-wire capacitance probes. The performance of the sensor is analyzed in terms of the flow structures detected by mini-conductance array probes.
基金the National High Technology Research and Development Program of China (863 Program) (No. 2002AA616050).
文摘To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overcomes the influence of the pipe wall. The data collection system is improved by using high performance IC (integrated circuit). Static tests of bubble flow, stratified flow and annular flow regime are carried out. Measurements are taken on bubble flow, stratified flow and slug flow. Results show that the new ECT system performs well on void fraction measurement of bubble flow and stratified flow, but the error of measurement for slug flow is more than 10%.
文摘The working principle of the pipeline intelligent pig and the structure of ultrasonic probe array used to detect defects in oil/gas pipeline are introduced. The effects of the array＇ s radial position in pipe on defect resolution are analyzed. The causes leading to radial positioning error are investigated. An algo- rithm for the radial self-positioning is presented. The experimental results show that the radial self-positioning algorithm can eliminate the array＇ s space position error effectively and improve the defect resolution.
文摘This paper presents the possibilities offered by fluorescence spectroscopy for the identification of vegetable oils such as soybean, sunflower, flax, walnut, corn, almond, sesame, olive and pumpkin oils. The probes under study have been excited with two types of sources： a laser diode （LD） and light-emitting diodes （LEDs） emitting in the UV and in the visible range. Total luminescence spectra were recorded by measuring the emission spectra in the range 350-720 nm at excitation wavelengths from 375 to 450 nm. The excitation-emission matrices have been obtained and two basic fluorescence regions in the visible have been outlined. On this basis the fluorescence spectra of the oils have been subdivided into three categories depending on the prevalence of the fluorescence maxima. The samples show differences in their fluorescence spectra. The latter fact shows that fluorescence spectroscopy can be used for the quick identification of edible oils. The fatty acid, the tocopherol, the beta-carotene and chlorophyll contents in the analyzed oils have been studied. It is shown that some of the types of oils differ significantly from each other by the first derivatives of their fluorescence spectra. There also exist color differences between the groups of vegetable oils under study.
文摘Understanding the holistic relationship between refinery production scheduling(RPS) and the cyber-physical production environment with smart scheduling is a new question posed in the study of process systems engineering. Here, we discuss state-of-the-art RSPs in the crude-oil refining field and present examples that illustrate how smart scheduling can impact operations in the high-performing chemical process industry. We conclude that, more than any traditional off-the-shelf RPS solution available today, flexible and integrative specialized modeling platforms will be increasingly necessary to perform decentralized and collaborative optimizations,since they are the technological alternatives closer to the advanced manufacturing philosophy.
