The orifice-plate flowmeter and ultrasonic flowmeter are used widely for natural gas flowrate measurement, and the measurement accuracy is affected greatly by flow state. Numerical simulation was used to study the flo...The orifice-plate flowmeter and ultrasonic flowmeter are used widely for natural gas flowrate measurement, and the measurement accuracy is affected greatly by flow state. Numerical simulation was used to study the flow of natural gas in the diffusion pipe, and the length of the irregular flow induced by the diffuser or rectifier was computed. Simulation results indicated that the flow in the diffusion pipe was three-dimensional turbulent flow and the steady state flow was restored at 17 pipe-diameters downstream of the diffuser. The rectifiers equipped in the diffusion pipe showed good rectification effect, notwithstanding the induced irregular flow. Downstream the rectifier, the flow became symmetrical and uniform in a shorter length than the case without a rectifier. For the diffusion pipe equipped with plate rectifier, tube rectifier and tube-plate rectifier, the lengths at which uniformly distributed flow was restored were 12, 6 and 5 pipe-diameters downstream the rectifier respectively. On the basis of simulation results, the minimum installation length for flowmeters equipped in the diffusion pipe was determined. This provides a new method for improving natural gas measurement accuracy.展开更多
Static cracking agent(SCA)is actively investigated as an alternative to explosive blasting for rock breakage due to its immense expansion property.SCA can eliminate the negative effects of shock,noise and harmful gase...Static cracking agent(SCA)is actively investigated as an alternative to explosive blasting for rock breakage due to its immense expansion property.SCA can eliminate the negative effects of shock,noise and harmful gases encountered in explosive blasting processes.Accurate measurement and deep understanding of the expansive properties of SCAs are important in their industrial application.An improved outer pipe method(OPM),termed the upper end surface method(UESM),is proposed in this paper to overcome the shortcomings of the OPM in the expansive pressure measurement of SCAs.Numerical simulation is used to proof the concept and a mathematical model established to relate the internal pressure and the radial strains at different positions in the upper end surface method test equipment.The new equipment is calibrated using oil pressure and strain measurements.The calibrated equipment is then used to measure the expansion pressure of SCA at three different water contents to proof its potential.The differences in the measurements with OPM and UESM at three different moisture contents are less than 4%.The experimental results confirm the accuracy and applicability of the more user friendly and less expensive UESM in the measurement of the expansive pressures of SCAs.展开更多
The diversity of ultrasound techniques used in oil and gas pipeline plants provides us with a wealth of information on how to exploit this technology when combined with other techniques, in order to improve the qualit...The diversity of ultrasound techniques used in oil and gas pipeline plants provides us with a wealth of information on how to exploit this technology when combined with other techniques, in order to improve the quality of analysis. The fundamental theory of ultrasonic nondestructive evaluation (NDE) technology is offered, along with practical limitations as related to two factors (wave types and transducers). The focus is limited to the two main techniques used in pipe plants: First, straight beam evaluation and second, angle beam evaluation. The depth of defect (DD) is calculated using straight beam ultrasonic in six different materials according to their relative longitudinal wave (LW) velocities. The materials and respective velocities of LW are: rolled aluminum (6420 m/s), mild steel (5960 m/s), stainless steel-347 (5790 m/s), rolled copper (5010 m/s), annealed copper (4760 m/s), and brass (4700 m/s). In each material eight defects are modeled;the first represents l00% of the material thickness (D), 50.8 mm. The other seven cases represent the DD, as 87.5% of the material thickness, 75%, 62.5%, 50%, 37.5%, 25%, and 12.5%, respectively. Using angle beam evaluation, several parameters are calculated for six different reflection angles (βR) (45°, 50°, 55°, 60°, 65° and 70°). The surface distance (SD), ½skip distance (SKD), full SKD, and 1½SKD,½sound path (SP) length, full SP, and 1½SP are calculated for each βR. The relationship of SKD and SP to the βR is graphed. A chief limitation is noted that ultrasound testing is heavily dependent on the expertise of the operator, and because the reading of the outcome is subjective, precision may be hard to achieve. This review also clarifies and discusses the options used in solving the industrial engineering problem, with a comprehensive historical summary of the information available in the literature. Merging various NDE inspection techniques into the testing of objects is discussed. Eventually, it is hoped to find a suitable technique combined with ultrasonic inspection to deliver highly effective remote testing.展开更多
A new water-cooling Gardon-type heat power measuring apparatus is designed to meet the need of heat power source management and distribution. The steady state measurement mathe- matic model of the apparatus is built u...A new water-cooling Gardon-type heat power measuring apparatus is designed to meet the need of heat power source management and distribution. The steady state measurement mathe- matic model of the apparatus is built up in theory and the system amplification coefficient is defined as the ratio of the heat power to the temperature difference of the device, with which the value of the measured source power can be calculated easily with the corresponding temperature difference. In order to obtain an optimal heat power measuring system, the coefficients that can influence the relationship between the amplification coefficient, the temperature difference, and the heat power are analyzed. On the basis of these analyses, a set of experimental device is constructed and a num- ber of experiments are carried on. Compared with the input heat power sample data, the error of the experimental measuring results is less than 4-2%, and the experimental measuring values are in good agreement with the calculated theoretical ones. The heat power measuring apparatus can be applied in heat flux or heat power measurement in other fields due to its simple structure and high accuracy.展开更多
文摘The orifice-plate flowmeter and ultrasonic flowmeter are used widely for natural gas flowrate measurement, and the measurement accuracy is affected greatly by flow state. Numerical simulation was used to study the flow of natural gas in the diffusion pipe, and the length of the irregular flow induced by the diffuser or rectifier was computed. Simulation results indicated that the flow in the diffusion pipe was three-dimensional turbulent flow and the steady state flow was restored at 17 pipe-diameters downstream of the diffuser. The rectifiers equipped in the diffusion pipe showed good rectification effect, notwithstanding the induced irregular flow. Downstream the rectifier, the flow became symmetrical and uniform in a shorter length than the case without a rectifier. For the diffusion pipe equipped with plate rectifier, tube rectifier and tube-plate rectifier, the lengths at which uniformly distributed flow was restored were 12, 6 and 5 pipe-diameters downstream the rectifier respectively. On the basis of simulation results, the minimum installation length for flowmeters equipped in the diffusion pipe was determined. This provides a new method for improving natural gas measurement accuracy.
基金funded by the State Key Research Development Program of China(No.2018YFC0604400)the National Science Foundation of China(Nos.51874068,52074062)+2 种基金the Fundamental Research Funds for the Central Universities(Nos.N2001003,N160107001,N180701016,N182608003,N2001001)the 111 Project(No.B17009)The authors also acknowledge Nazarbayev University for funding the research through its Collaborative Research Program(No.OPCRP2020014).
文摘Static cracking agent(SCA)is actively investigated as an alternative to explosive blasting for rock breakage due to its immense expansion property.SCA can eliminate the negative effects of shock,noise and harmful gases encountered in explosive blasting processes.Accurate measurement and deep understanding of the expansive properties of SCAs are important in their industrial application.An improved outer pipe method(OPM),termed the upper end surface method(UESM),is proposed in this paper to overcome the shortcomings of the OPM in the expansive pressure measurement of SCAs.Numerical simulation is used to proof the concept and a mathematical model established to relate the internal pressure and the radial strains at different positions in the upper end surface method test equipment.The new equipment is calibrated using oil pressure and strain measurements.The calibrated equipment is then used to measure the expansion pressure of SCA at three different water contents to proof its potential.The differences in the measurements with OPM and UESM at three different moisture contents are less than 4%.The experimental results confirm the accuracy and applicability of the more user friendly and less expensive UESM in the measurement of the expansive pressures of SCAs.
文摘The diversity of ultrasound techniques used in oil and gas pipeline plants provides us with a wealth of information on how to exploit this technology when combined with other techniques, in order to improve the quality of analysis. The fundamental theory of ultrasonic nondestructive evaluation (NDE) technology is offered, along with practical limitations as related to two factors (wave types and transducers). The focus is limited to the two main techniques used in pipe plants: First, straight beam evaluation and second, angle beam evaluation. The depth of defect (DD) is calculated using straight beam ultrasonic in six different materials according to their relative longitudinal wave (LW) velocities. The materials and respective velocities of LW are: rolled aluminum (6420 m/s), mild steel (5960 m/s), stainless steel-347 (5790 m/s), rolled copper (5010 m/s), annealed copper (4760 m/s), and brass (4700 m/s). In each material eight defects are modeled;the first represents l00% of the material thickness (D), 50.8 mm. The other seven cases represent the DD, as 87.5% of the material thickness, 75%, 62.5%, 50%, 37.5%, 25%, and 12.5%, respectively. Using angle beam evaluation, several parameters are calculated for six different reflection angles (βR) (45°, 50°, 55°, 60°, 65° and 70°). The surface distance (SD), ½skip distance (SKD), full SKD, and 1½SKD,½sound path (SP) length, full SP, and 1½SP are calculated for each βR. The relationship of SKD and SP to the βR is graphed. A chief limitation is noted that ultrasound testing is heavily dependent on the expertise of the operator, and because the reading of the outcome is subjective, precision may be hard to achieve. This review also clarifies and discusses the options used in solving the industrial engineering problem, with a comprehensive historical summary of the information available in the literature. Merging various NDE inspection techniques into the testing of objects is discussed. Eventually, it is hoped to find a suitable technique combined with ultrasonic inspection to deliver highly effective remote testing.
基金partly supported by the National Basic Research Program of China (2014CB046403)
文摘A new water-cooling Gardon-type heat power measuring apparatus is designed to meet the need of heat power source management and distribution. The steady state measurement mathe- matic model of the apparatus is built up in theory and the system amplification coefficient is defined as the ratio of the heat power to the temperature difference of the device, with which the value of the measured source power can be calculated easily with the corresponding temperature difference. In order to obtain an optimal heat power measuring system, the coefficients that can influence the relationship between the amplification coefficient, the temperature difference, and the heat power are analyzed. On the basis of these analyses, a set of experimental device is constructed and a num- ber of experiments are carried on. Compared with the input heat power sample data, the error of the experimental measuring results is less than 4-2%, and the experimental measuring values are in good agreement with the calculated theoretical ones. The heat power measuring apparatus can be applied in heat flux or heat power measurement in other fields due to its simple structure and high accuracy.
