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
Gas holdup is one of the key parameters in flotation process. Gas holdup as measured by a differential pressure method was investigated and the relative errors compared to the average gas holdup from the volume expans...Gas holdup is one of the key parameters in flotation process. Gas holdup as measured by a differential pressure method was investigated and the relative errors compared to the average gas holdup from the volume expansion method. The errors were used to establish optimum measurement positions. The results show that the measurement position should be in the middle of the column and in the region half way from the center to the wall (the half-radius). The gas holdup along the axial direction is lower at the bottom and higher at the top of the floatation column. The gas holdup along the radial direction is lower near the wall and higher near the center of the flotation column. The average gas holdup measure- ment can be replaced by regional gas holdup values.展开更多
In this study,we propose a new method for water holdup measurement of oil-in-water emulsions with a microwave resonance sensor(MRS).The angle and length of the electrode plate are optimized by HFSS simulation software...In this study,we propose a new method for water holdup measurement of oil-in-water emulsions with a microwave resonance sensor(MRS).The angle and length of the electrode plate are optimized by HFSS simulation software.Using a vector network analyzer(VNA),a static calibration experiment is conducted,and the resonant frequency distribution of oil-in-water emulsions is analyzed within an 80%–100%water holdup range.In addition,we observe and analyze the micron-sized oil bubble structure in the emulsifi ed state with an optical microscope.On this basis,a dynamic experiment of oil-in-water emulsions with high water cut and low velocity in a vertical upward pipe is conducted.S_(21) response curves of the MRS are obtained by the VNA under diff erent working conditions in real time.Finally,we analyze the relationship between the resonant frequency and water cut.Experimental results show that the MRS has an average resolution of 0.096%water cut for high water cut oil-in-water emulsions within the frequency range of 2.2–2.8 GHz.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supports for this work provided by the NationalKey Technology R&D Program in the 11th Five-Year Plan of China(No. 2008BAB31B03)
文摘Gas holdup is one of the key parameters in flotation process. Gas holdup as measured by a differential pressure method was investigated and the relative errors compared to the average gas holdup from the volume expansion method. The errors were used to establish optimum measurement positions. The results show that the measurement position should be in the middle of the column and in the region half way from the center to the wall (the half-radius). The gas holdup along the axial direction is lower at the bottom and higher at the top of the floatation column. The gas holdup along the radial direction is lower near the wall and higher near the center of the flotation column. The average gas holdup measure- ment can be replaced by regional gas holdup values.
基金supported by the National Natural Science Foundation of China(Grant Nos.42074142 and 51527805)。
文摘In this study,we propose a new method for water holdup measurement of oil-in-water emulsions with a microwave resonance sensor(MRS).The angle and length of the electrode plate are optimized by HFSS simulation software.Using a vector network analyzer(VNA),a static calibration experiment is conducted,and the resonant frequency distribution of oil-in-water emulsions is analyzed within an 80%–100%water holdup range.In addition,we observe and analyze the micron-sized oil bubble structure in the emulsifi ed state with an optical microscope.On this basis,a dynamic experiment of oil-in-water emulsions with high water cut and low velocity in a vertical upward pipe is conducted.S_(21) response curves of the MRS are obtained by the VNA under diff erent working conditions in real time.Finally,we analyze the relationship between the resonant frequency and water cut.Experimental results show that the MRS has an average resolution of 0.096%water cut for high water cut oil-in-water emulsions within the frequency range of 2.2–2.8 GHz.
