Based on high magnetic field helicon experiment(HMHX), HELIC code was used to study the effect of different magnetic fields on the power deposition under parabolic distribution. This paper is divided into three parts:...Based on high magnetic field helicon experiment(HMHX), HELIC code was used to study the effect of different magnetic fields on the power deposition under parabolic distribution. This paper is divided into three parts: preliminary calculation, actual discharge experiment and calculation. The results of preliminary calculation show that a magnetic field that is too small or too large cannot produce a good power deposition effect. When the magnetic field strength is 1200 Gs,a better power deposition can be obtained. The actual discharge experiment illustrates that the change of the magnetic field will have a certain influence on the discharge phenomenon. Finally, the results of verification calculation successfully verify the accuracy of the results of preliminary simulation. The results show that in the actual discharge experiment, it can achieve the best deposition effect when the magnetic field is 1185 Gs.展开更多
We conduct an electron magnetohydrodynamics magnetic reconnection experiment with guide-field in our Keda linear magnetized plasma device, in which two pulsed currents with the same direction are conducted in parallel...We conduct an electron magnetohydrodynamics magnetic reconnection experiment with guide-field in our Keda linear magnetized plasma device, in which two pulsed currents with the same direction are conducted in parallel with the axial direction of the main chamber of the device using two long aluminum sticks. After approximately 5μs, an X-type magnetic field line topology is formed at the center of the chamber. With the formation of the X-type topology of magnetic field lines, we can also find the rapid increase of the current and ratio of the common flux to the private flux in this area. Additionally, a reduction in the plasma density and the plasma density concentration along one pair of separatrices can also be found.展开更多
The oil and gas potential of the Yan'an Formation in the Ordos Basin has yet to be fully tapped. In this study, the pore structure, mobile fluid saturation, and water flooding micro-mechanism of the Yan'an For...The oil and gas potential of the Yan'an Formation in the Ordos Basin has yet to be fully tapped. In this study, the pore structure, mobile fluid saturation, and water flooding micro-mechanism of the Yan'an Formation sandstone are systematically studied through the application of a series of rock physics and fluid experiments. The results show that there is a good positive correlation between porosity and permeability, and the reservoirs are divided into types Ⅰ, Ⅱ, and Ⅲ. Mercury injection tests show that the average pore throat radius of the oil-bearing reservoir ranges from 1 to 7 μm. The displacement pressure of the Yan'an Formation is also relatively low, and it decreases from 0.1 MPa to 0.01 MPa as the rock porosity increases from 11% to 18%. NMR tests show that small (diameter <0.5 μm) and medium pores (diameter ranging from 0.5 to 2.5 μm) are predominant in the reservoir. Different types of reservoirs have different characteristics of relative permeability curve. In addition, when the average oil recovery rate is less than 1 ml/min, the oil displacement efficiency increases faster. However, when the average oil recovery rate is between 1–3.5 ml/min, the oil displacement efficiency is maintained at around 27%–30%. Physical properties of the reservoir, pore-throat structure, experimental pressure difference, and pore volume injected — all have significant effects on oil displacement efficiency. For Type Ⅰ and Type Ⅱ reservoirs, the increase of the pore volume injected has a significant effect on oil displacement efficiency. However, for Type Ⅲ reservoirs, the change of pore volume injected has insignificant effect on oil displacement efficiency. This study provides a reference for the formulation of estimated ultimate recovery (EUR) measures for similar sandstone reservoirs.展开更多
Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical phenomena.We use the Martin-Pup...Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical phenomena.We use the Martin-Puplett interferometer(MPI)polarimeter to probe the peripheral magnetic fields generated in the common magnetic reconnection configuration,two separated coplanar plane targets,in laser-target interaction.We introduce a new method that can obtain polarization information from the interference pattern instead of the sinusoidal function fitting of the intensity.A bidirectional magnetic field is observed from the side view,which is consistent with the magneto-hydro-dynamical(MHD)simulation results of self-generated magnetic field reconnection.We find that the cancellation of reverse magnetic fields after averaging and integration along the observing direction could reduce the magnetic field strength by one to two orders of magnitude.It indicates that imaging resolution can significantly affect the accuracy of measured magnetic field strength.展开更多
The casing damage has been a big problem in oilfield production. The current detection methods mostly are used after casing damage, which is not very effective. With the rapid development of China's offshore oil i...The casing damage has been a big problem in oilfield production. The current detection methods mostly are used after casing damage, which is not very effective. With the rapid development of China's offshore oil industry, the number of offshore oil wells is becoming larger and larger. Because the cost of offshore oil well is very high, the casing damage will cause huge economic losses. What's more, it can also bring serious pollution to marine environment. So the effective methods of detecting casing damage are required badly. The accumulation of stress is the main reason for the casing damage. Magnetic anisotropy technique based on counter magnetostriction effect can detect the stress of casing in real time and help us to find out the hidden dangers in time. It is essential for us to prevent the casing damage from occurring. However, such technique is still in the development stage. Previous studies mostly got the relationship between stress and magnetic signals by physical experiment, and the study of physical mechanism in relative magnetic permeability connecting the stress and magnetic signals is rarely reported. The present paper uses the ANSYS to do the three-dimensional finite element numerical simulation to study how the relative magnetic permeability works for the oil casing model. We find that the quantitative relationship between the stress' s variation and magnetic induction intensity's variation is: Δδ =K* ΔB, K = 8.04×109, which is proved correct by physical experiment.展开更多
We investigate equilibrium height of a flux rope, and its internal equilib- rium in a realistic plasma environment by carrying out numerical simulations of the evolution of systems including a current-carrying flux ro...We investigate equilibrium height of a flux rope, and its internal equilib- rium in a realistic plasma environment by carrying out numerical simulations of the evolution of systems including a current-carrying flux rope. We find that the equilib- rium height of a flux rope is approximately described by a power-law function of the relative strength of the background field. Our simulations indicate that the flux rope can escape more easily from a weaker background field. This further confirms that a catastrophe in the magnetic configuration of interest can be triggered by a decrease in strength of the background field. Our results show that it takes some time to reach internal equilibrium depending on the initial state of the flux rope. The plasma flow inside the flux rope due to the adjustment for the internal equilibrium of the flux rope remains small and does not last very long when the initial state of the flux rope com- mences from the stable branch of the theoretical equilibrium curve. This work also confirms the influence of the initial radius of the flux rope in its evolution; the results indicate that a flux rope with a larger initial radius erupts more easily. In addition, by using a realistic plasma environment and a much higher resolution in our simulations, we notice some different characteristics compared to previous studies in Forbes.展开更多
<div style="text-align:justify;"> The purpose of this study is to prevent the occurrence of falls by defining the symptoms of falls and detecting them in advance. The focus of the study is on the speci...<div style="text-align:justify;"> The purpose of this study is to prevent the occurrence of falls by defining the symptoms of falls and detecting them in advance. The focus of the study is on the specific definition of “Falling Symptoms”. In this regard, we conducted a questionnaire survey on people of different ages to obtain the state of themselves and their surroundings when they fell down. In addition, we used the elderly simulated experience kit to achieve the purpose of using young people to replace the elderly. Young people were asked to walk on different roads in different shoes with and without elderly simulated experience kit and photographed them with a high-speed camera to observe the changes of their muscles and joints. We also simulated the movement of center of gravity of the people with and without elderly simulated experience kit by a pressure distribution sensor mat. </div>展开更多
The question of what magnetism is vital to quantum physics. We know what all other quantum phenomenon is, but we did not know what magnetism is. It is not enough to say it is a force because of a charge. That force mu...The question of what magnetism is vital to quantum physics. We know what all other quantum phenomenon is, but we did not know what magnetism is. It is not enough to say it is a force because of a charge. That force must be something, for consistencies sake it had to be tested. This paper was written in order to confirm the results that were received in the experiments that took place that led to the paper “Magnetism: Insights from the Thomas Young Experiment” where it was concluded the magnetic phenomenon is both a particle and a wave. Will different interference patterns confirm a khumalon and wave like behaviour? The khumalon is the name of the particle associated with magnetic phenomenon. This paper concludes by confirming what was discovered in mentioned paper. Magnetism organizes into a wave no matter the interference. Understanding this reality, it allows us to understand what is happening with simple magnetic interactions. When like poles meet because they can not occupy the same space they push each other. Opposite poles are antiparticles to each other and annihilate each other. South pole scientifically speaking is not attracted to the north pole, the reason why the magnets slam each other is because they are closing a magnetic vacuum caused by the particles annihilating each other. We can now start theorizing on why a lodestone attracts iron because we now know we are dealing with a particle.展开更多
The question of what magnetism is vital to quantum physics. We know what all other quantum phenomenon is, but we did not know what magnetism is. It is not enough to say it is a force because of a charge. That force mu...The question of what magnetism is vital to quantum physics. We know what all other quantum phenomenon is, but we did not know what magnetism is. It is not enough to say it is a force because of a charge. That force must be something, for consistencies sake it had to be tested. This paper was written in order to confirm the results that were received in the experiments that took place that led to the paper “Magnetism: Insights from the Thomas Young Experiment” where it was concluded the magnetic phenomenon is both a particle and a wave. Will different interference patterns confirm a khumalon and wave like behaviour? The khumalon is the name of the particle associated with magnetic phenomenon. This paper concludes by confirming what was discovered in mentioned paper. Magnetism organizes into a wave no matter the interference. Understanding this reality, it allows us to understand what is happening with simple magnetic interactions. When like poles meet because they can not occupy the same space they push each other. Opposite poles are antiparticles to each other and annihilate each other. South pole scientifically speaking is not attracted to the north pole, the reason why the magnets slam each other is because they are closing a magnetic vacuum caused by the particles annihilating each other. We can now start theorizing on why a lodestone attracts iron because we now know we are dealing with a particle.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 11975163 and 12175160)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)。
文摘Based on high magnetic field helicon experiment(HMHX), HELIC code was used to study the effect of different magnetic fields on the power deposition under parabolic distribution. This paper is divided into three parts: preliminary calculation, actual discharge experiment and calculation. The results of preliminary calculation show that a magnetic field that is too small or too large cannot produce a good power deposition effect. When the magnetic field strength is 1200 Gs,a better power deposition can be obtained. The actual discharge experiment illustrates that the change of the magnetic field will have a certain influence on the discharge phenomenon. Finally, the results of verification calculation successfully verify the accuracy of the results of preliminary simulation. The results show that in the actual discharge experiment, it can achieve the best deposition effect when the magnetic field is 1185 Gs.
基金Supported by the National Natural Science Foundation of China under Grant Nos 41331067 and 41527804the Key Research Program of Frontier Sciences of Chinese Academy of Sciences under Grant No QYZDJ-SSW-DQC010the Fundamental Research Funds for the Central Universities
文摘We conduct an electron magnetohydrodynamics magnetic reconnection experiment with guide-field in our Keda linear magnetized plasma device, in which two pulsed currents with the same direction are conducted in parallel with the axial direction of the main chamber of the device using two long aluminum sticks. After approximately 5μs, an X-type magnetic field line topology is formed at the center of the chamber. With the formation of the X-type topology of magnetic field lines, we can also find the rapid increase of the current and ratio of the common flux to the private flux in this area. Additionally, a reduction in the plasma density and the plasma density concentration along one pair of separatrices can also be found.
基金supported by the Guiding Science and Technology Planning Project of Daqing(Grant No.zd-2021-36)Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province,China(Grant No.LBH-Z21084)Natural Science Foundation of Heilongjiang Province(Grant No.LH 2022E019).
文摘The oil and gas potential of the Yan'an Formation in the Ordos Basin has yet to be fully tapped. In this study, the pore structure, mobile fluid saturation, and water flooding micro-mechanism of the Yan'an Formation sandstone are systematically studied through the application of a series of rock physics and fluid experiments. The results show that there is a good positive correlation between porosity and permeability, and the reservoirs are divided into types Ⅰ, Ⅱ, and Ⅲ. Mercury injection tests show that the average pore throat radius of the oil-bearing reservoir ranges from 1 to 7 μm. The displacement pressure of the Yan'an Formation is also relatively low, and it decreases from 0.1 MPa to 0.01 MPa as the rock porosity increases from 11% to 18%. NMR tests show that small (diameter <0.5 μm) and medium pores (diameter ranging from 0.5 to 2.5 μm) are predominant in the reservoir. Different types of reservoirs have different characteristics of relative permeability curve. In addition, when the average oil recovery rate is less than 1 ml/min, the oil displacement efficiency increases faster. However, when the average oil recovery rate is between 1–3.5 ml/min, the oil displacement efficiency is maintained at around 27%–30%. Physical properties of the reservoir, pore-throat structure, experimental pressure difference, and pore volume injected — all have significant effects on oil displacement efficiency. For Type Ⅰ and Type Ⅱ reservoirs, the increase of the pore volume injected has a significant effect on oil displacement efficiency. However, for Type Ⅲ reservoirs, the change of pore volume injected has insignificant effect on oil displacement efficiency. This study provides a reference for the formulation of estimated ultimate recovery (EUR) measures for similar sandstone reservoirs.
基金Project supported by the National Key R&D Program of China (Grant Nos.2022YFA1603200 and 2022YFA1603203)the National Natural Science Foundation of China (Grant Nos.12075030,12135001,12175018,and 12325305)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDA25030700)the Research Grants Council of Hong (Grant No.14307118)the Youth Interdisciplinary Team (Grant No.JCTD-2022-05)supported by the China Postdoctoral International Exchange Program。
文摘Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical phenomena.We use the Martin-Puplett interferometer(MPI)polarimeter to probe the peripheral magnetic fields generated in the common magnetic reconnection configuration,two separated coplanar plane targets,in laser-target interaction.We introduce a new method that can obtain polarization information from the interference pattern instead of the sinusoidal function fitting of the intensity.A bidirectional magnetic field is observed from the side view,which is consistent with the magneto-hydro-dynamical(MHD)simulation results of self-generated magnetic field reconnection.We find that the cancellation of reverse magnetic fields after averaging and integration along the observing direction could reduce the magnetic field strength by one to two orders of magnitude.It indicates that imaging resolution can significantly affect the accuracy of measured magnetic field strength.
基金supported by the National Natural Science Foundation of China(No.41174157)
文摘The casing damage has been a big problem in oilfield production. The current detection methods mostly are used after casing damage, which is not very effective. With the rapid development of China's offshore oil industry, the number of offshore oil wells is becoming larger and larger. Because the cost of offshore oil well is very high, the casing damage will cause huge economic losses. What's more, it can also bring serious pollution to marine environment. So the effective methods of detecting casing damage are required badly. The accumulation of stress is the main reason for the casing damage. Magnetic anisotropy technique based on counter magnetostriction effect can detect the stress of casing in real time and help us to find out the hidden dangers in time. It is essential for us to prevent the casing damage from occurring. However, such technique is still in the development stage. Previous studies mostly got the relationship between stress and magnetic signals by physical experiment, and the study of physical mechanism in relative magnetic permeability connecting the stress and magnetic signals is rarely reported. The present paper uses the ANSYS to do the three-dimensional finite element numerical simulation to study how the relative magnetic permeability works for the oil casing model. We find that the quantitative relationship between the stress' s variation and magnetic induction intensity's variation is: Δδ =K* ΔB, K = 8.04×109, which is proved correct by physical experiment.
基金Supported by the National Natural Science Foundation of China
文摘We investigate equilibrium height of a flux rope, and its internal equilib- rium in a realistic plasma environment by carrying out numerical simulations of the evolution of systems including a current-carrying flux rope. We find that the equilib- rium height of a flux rope is approximately described by a power-law function of the relative strength of the background field. Our simulations indicate that the flux rope can escape more easily from a weaker background field. This further confirms that a catastrophe in the magnetic configuration of interest can be triggered by a decrease in strength of the background field. Our results show that it takes some time to reach internal equilibrium depending on the initial state of the flux rope. The plasma flow inside the flux rope due to the adjustment for the internal equilibrium of the flux rope remains small and does not last very long when the initial state of the flux rope com- mences from the stable branch of the theoretical equilibrium curve. This work also confirms the influence of the initial radius of the flux rope in its evolution; the results indicate that a flux rope with a larger initial radius erupts more easily. In addition, by using a realistic plasma environment and a much higher resolution in our simulations, we notice some different characteristics compared to previous studies in Forbes.
文摘<div style="text-align:justify;"> The purpose of this study is to prevent the occurrence of falls by defining the symptoms of falls and detecting them in advance. The focus of the study is on the specific definition of “Falling Symptoms”. In this regard, we conducted a questionnaire survey on people of different ages to obtain the state of themselves and their surroundings when they fell down. In addition, we used the elderly simulated experience kit to achieve the purpose of using young people to replace the elderly. Young people were asked to walk on different roads in different shoes with and without elderly simulated experience kit and photographed them with a high-speed camera to observe the changes of their muscles and joints. We also simulated the movement of center of gravity of the people with and without elderly simulated experience kit by a pressure distribution sensor mat. </div>
文摘The question of what magnetism is vital to quantum physics. We know what all other quantum phenomenon is, but we did not know what magnetism is. It is not enough to say it is a force because of a charge. That force must be something, for consistencies sake it had to be tested. This paper was written in order to confirm the results that were received in the experiments that took place that led to the paper “Magnetism: Insights from the Thomas Young Experiment” where it was concluded the magnetic phenomenon is both a particle and a wave. Will different interference patterns confirm a khumalon and wave like behaviour? The khumalon is the name of the particle associated with magnetic phenomenon. This paper concludes by confirming what was discovered in mentioned paper. Magnetism organizes into a wave no matter the interference. Understanding this reality, it allows us to understand what is happening with simple magnetic interactions. When like poles meet because they can not occupy the same space they push each other. Opposite poles are antiparticles to each other and annihilate each other. South pole scientifically speaking is not attracted to the north pole, the reason why the magnets slam each other is because they are closing a magnetic vacuum caused by the particles annihilating each other. We can now start theorizing on why a lodestone attracts iron because we now know we are dealing with a particle.
文摘The question of what magnetism is vital to quantum physics. We know what all other quantum phenomenon is, but we did not know what magnetism is. It is not enough to say it is a force because of a charge. That force must be something, for consistencies sake it had to be tested. This paper was written in order to confirm the results that were received in the experiments that took place that led to the paper “Magnetism: Insights from the Thomas Young Experiment” where it was concluded the magnetic phenomenon is both a particle and a wave. Will different interference patterns confirm a khumalon and wave like behaviour? The khumalon is the name of the particle associated with magnetic phenomenon. This paper concludes by confirming what was discovered in mentioned paper. Magnetism organizes into a wave no matter the interference. Understanding this reality, it allows us to understand what is happening with simple magnetic interactions. When like poles meet because they can not occupy the same space they push each other. Opposite poles are antiparticles to each other and annihilate each other. South pole scientifically speaking is not attracted to the north pole, the reason why the magnets slam each other is because they are closing a magnetic vacuum caused by the particles annihilating each other. We can now start theorizing on why a lodestone attracts iron because we now know we are dealing with a particle.