This page has only limited features, please log in for full access.
Tungsten armors are arranged on the plasma side of the blankets to protect the first wall in a fusion device, such as China Fusion Engineering Test Reactor (CFETR) and European Demonstration Power Plant (EU DEMO). Tungsten armors will produce a huge eddy current and Electromagnetic (EM) load under plasma disruption due to their high conductivity and strong magnetic field environment, which will cause the blankets to be subjected to a substantial eddy current and thus heat load, thermal stress and mechanical stress, that potential could damage blankets. To evaluate the effect of the tungsten armor on the electromagnetic characteristics of blanket, electromagnetic calculation method verification is carried out. And the electromagnetic finite element model of blanket is established by using ANSYS, and the eddy current distribution in the first wall is calculated. Effects of the tungsten armor, split size and gap size of the tungsten armor on the eddy current of blanket first wall and effect of the tungsten armor on the EM force of blanket are researched. And the influence of different tungsten armor design on the thermal stress distribution of blanket first wall is also studied. The study results will provide an important reference for the blanket design of the fusion device.
Shanwen Zhang; Min Kong; Lin Zhu; Shuangsong Du; Changle Feng. Effect of tungsten armor on electromagnetic characteristics of blanket for the fusion device under plasma disruption. Fusion Engineering and Design 2021, 173, 112832 .
AMA StyleShanwen Zhang, Min Kong, Lin Zhu, Shuangsong Du, Changle Feng. Effect of tungsten armor on electromagnetic characteristics of blanket for the fusion device under plasma disruption. Fusion Engineering and Design. 2021; 173 ():112832.
Chicago/Turabian StyleShanwen Zhang; Min Kong; Lin Zhu; Shuangsong Du; Changle Feng. 2021. "Effect of tungsten armor on electromagnetic characteristics of blanket for the fusion device under plasma disruption." Fusion Engineering and Design 173, no. : 112832.
The study of the influence of the nanoparticle volume fraction and aspect ratio of microchannels on the fluid flow and heat transfer characteristics of nanofluids in microchannels is important in the optimal design of heat dissipation systems with high heat flux. In this work, the computational fluid dynamics method was adopted to simulate the flow and heat transfer characteristics of two types of water-Al2O3 nanofluids with two different volume fractions and five types of microchannel heat sinks with different aspect ratios. Results showed that increasing the nanoparticle volume fraction reduced the average temperature of the heat transfer interface and thereby improved the heat transfer capacity of the nanofluids. Meanwhile, the increase of the nanoparticle volume fraction led to a considerable increase in the pumping power of the system. Increasing the aspect ratio of the microchannel effectively improved the heat transfer capacity of the heat sink. Moreover, increasing the aspect ratio effectively reduced the average temperature of the heating surface of the heat sink without significantly increasing the flow resistance loss. When the aspect ratio exceeded 30, the heat transfer coefficient did not increase with the increase of the aspect ratio. The results of this work may offer guiding significance for the optimal design of high heat flux microchannel heat sinks.
Huajie Wu; Shanwen Zhang. Numerical Study on the Fluid Flow and Heat Transfer Characteristics of Al2O3-Water Nanofluids in Microchannels of Different Aspect Ratio. Micromachines 2021, 12, 868 .
AMA StyleHuajie Wu, Shanwen Zhang. Numerical Study on the Fluid Flow and Heat Transfer Characteristics of Al2O3-Water Nanofluids in Microchannels of Different Aspect Ratio. Micromachines. 2021; 12 (8):868.
Chicago/Turabian StyleHuajie Wu; Shanwen Zhang. 2021. "Numerical Study on the Fluid Flow and Heat Transfer Characteristics of Al2O3-Water Nanofluids in Microchannels of Different Aspect Ratio." Micromachines 12, no. 8: 868.
To achieve the purpose of Ginkgo biloba leaves continuous harvesting, a ginkgo leaf picking device is designed. The device is consisted of a picking executive composed from a round rod picking hand and a rotating drum, a frame, a motor, a motor base, a coupling, a bearing seat, a motor support frame, a deciduous box, and a connecting screw. And the picking theoretical analysis and calculation are carried out. Finally, the feasibility of the design is verified by adjusting the tilt angle and motor speed of the picking device. The experimental results show that when the inclination angle between the picking device and the horizontal plane is 30° and the motor speed is 120 r/min, the damage rate of Ginkgo biloba leaves is 1.52%. The net collection rate is 94.29%, and the damage degree of branch and stem is mild.
Shanwen Zhang; Zhongliu Wang; Li Wang; Sian Liu; Yanjun Zhang; Hong Miao; Min Dai; Sixing Liu. Design and experimental study of ginkgo leaf picking device. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 2021, 1 .
AMA StyleShanwen Zhang, Zhongliu Wang, Li Wang, Sian Liu, Yanjun Zhang, Hong Miao, Min Dai, Sixing Liu. Design and experimental study of ginkgo leaf picking device. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science. 2021; ():1.
Chicago/Turabian StyleShanwen Zhang; Zhongliu Wang; Li Wang; Sian Liu; Yanjun Zhang; Hong Miao; Min Dai; Sixing Liu. 2021. "Design and experimental study of ginkgo leaf picking device." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science , no. : 1.
Laser welding of transparent materials, including glasses, established in the recent years. This study reports the results of the theoretical with experimental validation to transient temperature and stress fields on bonding small glass pieces to solder glass by laser welding. A 3D finite element model of bonding small glass pieces to solder glass by laser welding is developed and validated with experimental micro-structural analysis. An influence of laser average power and welding speed on the temperature field and stress field during welding is studied. A range of average laser power and welding speed, with a standard of the appropriate temperatures and ultimate stresses of sealing during laser welding, are determined. The results show that in the range of laser average power of 45~75 W and welding speed of 1–2 mm/s, the heat source central temperature increases with an increase of laser average power or the decrease of welding speed, and the corresponding maximum temperature exceeds 650 °C. The maximum transient thermal stress is calculated to be 152 MPa, it appeared at the boundary of the upper glass interface. The boundary stress at the front end of the heat source and the transient thermal stress at the inflection point are larger than the transient thermal stress at the middle point. The experimental and theoretical results show that the melting layer has excellent morphology and mechanical properties at the average laser power of 65 W and welding speed of 90 mm/min, which is applicable for the bonding of small glass pieces to solder glass by laser welding.
Shanwen Zhang; Min Kong; Hong Miao; Saim Memon; Yanjun Zhang; Sixing Liu. Transient temperature and stress fields on bonding small glass pieces to solder glass by laser welding: Numerical modelling and experimental validation. Solar Energy 2020, 209, 350 -362.
AMA StyleShanwen Zhang, Min Kong, Hong Miao, Saim Memon, Yanjun Zhang, Sixing Liu. Transient temperature and stress fields on bonding small glass pieces to solder glass by laser welding: Numerical modelling and experimental validation. Solar Energy. 2020; 209 ():350-362.
Chicago/Turabian StyleShanwen Zhang; Min Kong; Hong Miao; Saim Memon; Yanjun Zhang; Sixing Liu. 2020. "Transient temperature and stress fields on bonding small glass pieces to solder glass by laser welding: Numerical modelling and experimental validation." Solar Energy 209, no. : 350-362.
Laser sealing for vacuum plate glass is a key step in developing the cost-effective smart vacuum-glass window for the drive towards net-zero energy buildings. In this paper, the pores, cracks, and interface with laser welding are analyzed in depth using PbO-TiO2-SiO2-RxOy system sealing solder to prepare vacuum flat glass. The microstructure of the sealing layer was analyzed by a BX41M-LED metallographic microscope, and the interfacial bonding characteristics were observed by thermal field emission scanning electron microscopy (SEM). The solder was analyzed by an energy spectrometer, and the influence of laser power, sealing temperature, and sealing speed on the gas holes and the crack sand interface separation of the sealing layer are reported. The results show that when the laser power reached 80 W at the welding speed of 2 mm/s, the bulk solder disappeared to most of the quantity and the sealing surface density was higher, due to which negligible pores and micro cracks were found. Thus, the sealing quality of the sealing layer is considered to be suitable when the temperature of 470 °C was maintained and the solder has 68.93% of Pb and 3.04% Si in the atom fraction to achieve the wet the glass substrate surface whilst improving the bonding quality.
Hong Miao; Lingcong Zhang; Sixing Liu; Shanwen Zhang; Saim Memon; Bi Zhu. Laser Sealing for Vacuum Plate Glass with PbO-TiO2-SiO2-RxOy Solder. Sustainability 2020, 12, 3118 .
AMA StyleHong Miao, Lingcong Zhang, Sixing Liu, Shanwen Zhang, Saim Memon, Bi Zhu. Laser Sealing for Vacuum Plate Glass with PbO-TiO2-SiO2-RxOy Solder. Sustainability. 2020; 12 (8):3118.
Chicago/Turabian StyleHong Miao; Lingcong Zhang; Sixing Liu; Shanwen Zhang; Saim Memon; Bi Zhu. 2020. "Laser Sealing for Vacuum Plate Glass with PbO-TiO2-SiO2-RxOy Solder." Sustainability 12, no. 8: 3118.
The neutron shielding glass is widely used in nuclear/fusion plants. To improve its temperature resistance and heat insulation, a Gadolinium (Gd)-containing laminate vacuum multiple glass is proposed by using the vacuum insulation method. A 3D finite element model validated by theoretical calculation was developed to analyse the heat transfer path and numerical simulation of the multiple glass was carried out to obtain the temperature distribution and the maximum temperatures of the organic glass in relation to dynamic working temperatures, the sealing agent width, view size, and vacuum thermal conductivity. The results show that the vacuum layer between common glasses can make the work temperature of neutron shielding glass increase. The multiple glass has good heat-shielding performance and it is expected to work in a high-temperature environment. In addition, the vacuum layer between the common glasses and the sealing agent width decay with respect to the view size and vacuum thermal conductivity show an increase in the working temperature of the neutron shielding glass. It was concluded that the order of affecting the temperatures of the organic glass follows the pattern of: view size > vacuum thermal conductivity > sealing agent width.
Shanwen Zhang; Min Kong; Saim Memon; Hong Miao; Yanjun Zhang; Sixing Liu. Thermal Analysis of a New Neutron Shielding Vacuum Multiple Glass. Sustainability 2020, 12, 3083 .
AMA StyleShanwen Zhang, Min Kong, Saim Memon, Hong Miao, Yanjun Zhang, Sixing Liu. Thermal Analysis of a New Neutron Shielding Vacuum Multiple Glass. Sustainability. 2020; 12 (8):3083.
Chicago/Turabian StyleShanwen Zhang; Min Kong; Saim Memon; Hong Miao; Yanjun Zhang; Sixing Liu. 2020. "Thermal Analysis of a New Neutron Shielding Vacuum Multiple Glass." Sustainability 12, no. 8: 3083.
To explore the effect of welding speed on the micromorphology and mechanical properties of the laser-welded vacuum plate glazing joints, this paper introduced the research status of the laser welding vacuum glazing and then carried out the preparation for experimental materials. This paper also analyzed the microstructure, the cause of the pores, and the mechanical properties of the sealing layer. The results show that the smaller the welding speed is, the more fully the solder melts. When the welding speed is 80 mm/min, the sealing layer generates the large thermal stress due to excessive laser input energy, which results in many connected cracks in the sealing layer. The porosity of the sealing layer increases with the increase of the welding speed. The thickness of the interface reaction wetting layer decreases with the increase of the welding speed. The hardness, tensile strength, and shear strength of the sealing layer will increase first and then decrease with the increase of welding speed. These studies can provide the theoretical basis for laser sealing manufacturing of vacuum plate glazing.
Hong Miao; Chong Li; Qiang He; Shanwen Zhang; Yanjun Zhang; Sixing Liu. The Effect of Welding Speed on the Micromorphology and Mechanical Properties of Laser-Sealed Vacuum Flat Glazing Joints. Advances in Materials Science and Engineering 2019, 2019, 1 -5.
AMA StyleHong Miao, Chong Li, Qiang He, Shanwen Zhang, Yanjun Zhang, Sixing Liu. The Effect of Welding Speed on the Micromorphology and Mechanical Properties of Laser-Sealed Vacuum Flat Glazing Joints. Advances in Materials Science and Engineering. 2019; 2019 ():1-5.
Chicago/Turabian StyleHong Miao; Chong Li; Qiang He; Shanwen Zhang; Yanjun Zhang; Sixing Liu. 2019. "The Effect of Welding Speed on the Micromorphology and Mechanical Properties of Laser-Sealed Vacuum Flat Glazing Joints." Advances in Materials Science and Engineering 2019, no. : 1-5.
To explore the mechanism of the pore formation in the laser-welded vacuum plate glazing sealing layer, a vacuum plate glazing laser side sealing test was carried out. The influence of the pulse current, pulse duration time, pulse frequency and welding speed on the pores of the sealing layer was studied by means of scanning electron microscopy (SEM) and metallographic microscopy, and the cause of the pores is analyzed. The results show that the porosity decreases with the increase of the pulse current. When the pulse current is 160 A, the pores are the fewest and smallest, and the porosity is only 0.1%. The porosity of the sealing layer decreases first and then increases with the increase of the pulse duration time. The porosity decreases first and then increases with the increase of the pulse frequency. When the pulse frequency is 18 Hz, the porosity is the least, at only 0.08%. The porosity of the sealing layer increases with the increase of the welding speed. When the welding speed is 80, 90, 100 and 110 mm/min, the porosity is 0.02, 0.08, 0.63 and 0.89%, respectively. These studies can provide a theoretical basis for laser sealing manufacturing of vacuum plate glazing.
Shanwen Zhang; Chong Li; Hong Miao; Qiang He. The Influence of Welding Process Parameters on Pore Formation in Pulsed Laser-Welded Vacuum Plate Glazing. Materials 2019, 12, 1790 .
AMA StyleShanwen Zhang, Chong Li, Hong Miao, Qiang He. The Influence of Welding Process Parameters on Pore Formation in Pulsed Laser-Welded Vacuum Plate Glazing. Materials. 2019; 12 (11):1790.
Chicago/Turabian StyleShanwen Zhang; Chong Li; Hong Miao; Qiang He. 2019. "The Influence of Welding Process Parameters on Pore Formation in Pulsed Laser-Welded Vacuum Plate Glazing." Materials 12, no. 11: 1790.
Reduced Activation Ferritic/Martensitic (RAFM) steel is selected as structural material for the water cooled ceramic breeder (WCCB) blanket for China Fusion Engineering Test Reactor (CFETR). Due to the magnetization of RAFM steel, the toroidal field (TF) ripple is generated by the WCCB blanket. The TF ripple induces significant losses of high-energy particles, and then causes issues of heat load on plasma-facing components (PFCs) and energy balance of plasma. Hence, TF ripple generated by WCCB blanket is calculated, and several effective optimization methods are explored in this paper. The simulation results indicate that TF ripple in plasma target separatrix is greater than design limits (δTF<0.5%) in present design. Four methods are employed to study and evaluate the effect of decreasing TF ripple including installing ferromagnetic inserts, using correction coils, changing the related parameter of diagnostic system and moving the WCCB blanket, respectively. Based on the analysis results, it is found that these four methods can reduce TF ripple to some extend through different optimizing methods. The location of five TF ripple peaks of a 22.5° sector are at 0°, ±3.07° and ±7.67° respectively. The TF ripple can only reduce from 0.25% to 0.21% at ±3.07° plane using optimization method of installing ferromagnetic inserts. The rest of the location has almost little impact. The TF ripple can only reduce from 0.31% to 0.20% at 0° plane using correction coils, but the peak value will increase to 0.33% at ±3.07° plane. Moving diagnostic system 40 mm outward in radial direction will effectively decrease the TF ripple from 3.54% to 0.37% at -3.07° plane. Moving WCCB blankets 20 mm outward in radial direction makes the maximum TF ripple from 0.56% to 0.09%. Discussions are made about the effect of the optimization methods for reducing TF ripple.
Mingzhun Lei; Songlin Liu; Yuntao Song; Shanwen Zhang; Shuling Xu. Evaluation on the method of reducing CFETR TF ripple generated by WCCB blanket. Fusion Engineering and Design 2019, 145, 23 -28.
AMA StyleMingzhun Lei, Songlin Liu, Yuntao Song, Shanwen Zhang, Shuling Xu. Evaluation on the method of reducing CFETR TF ripple generated by WCCB blanket. Fusion Engineering and Design. 2019; 145 ():23-28.
Chicago/Turabian StyleMingzhun Lei; Songlin Liu; Yuntao Song; Shanwen Zhang; Shuling Xu. 2019. "Evaluation on the method of reducing CFETR TF ripple generated by WCCB blanket." Fusion Engineering and Design 145, no. : 23-28.
China Fusion Engineering Test Reactor (CFETR), the next fusion device in China, is proposed to bridge the gaps between ITER and the demonstration reactor (DEMO). The Water Cooled Ceramic Breeder (WCCB) blanket, one candidate option of breeding blanket conception for CFETR, impacts the toroidal field (TF) ripple in CFETR, as the reduced activation ferritic/martensitic (RAFM) steel was used as its structure material. The purpose of this paper is to investigate and evaluate the ripple effect of WCCB blanket on TF ripple in CFETR. An analysis is performed using three-dimensional finite element model with 16 TF coils and WCCB blanket modules. ANSYS code is employed for this study. The results indicated that the TF ripple was less than 0.5% at all points in target separatrix when it was estimated with TF coils only. We also calculated TF ripple in case of WCCB blanket modules and various port configuration schemes. It is found that TF ripple cannot meet the design requirements by the presence of WCCB blanket modules, even in difference port configuration. Discussions are made on the implication of the WCCB blanket modules and ports on TF ripple. Potential methods for reducing the TF ripple are studied in this paper.
Mingzhun Lei; Kun Lu; Yuntao Song; Shanwen Zhang; Ming Wang; Shuling Xu; Kun Xu; Songlin Liu. Study on ripple effect of ferromagnetic WCCB blanket modules in CFETR. Fusion Engineering and Design 2019, 146, 1192 -1197.
AMA StyleMingzhun Lei, Kun Lu, Yuntao Song, Shanwen Zhang, Ming Wang, Shuling Xu, Kun Xu, Songlin Liu. Study on ripple effect of ferromagnetic WCCB blanket modules in CFETR. Fusion Engineering and Design. 2019; 146 ():1192-1197.
Chicago/Turabian StyleMingzhun Lei; Kun Lu; Yuntao Song; Shanwen Zhang; Ming Wang; Shuling Xu; Kun Xu; Songlin Liu. 2019. "Study on ripple effect of ferromagnetic WCCB blanket modules in CFETR." Fusion Engineering and Design 146, no. : 1192-1197.
The Wendelstein 7-X (W7-X), the largest modular stellarator in the world, is in operation at Max Planck Institute for Plasma Physics in Greifswald, Germany. The magnet system of the W7-X consists of 50 nonplanar and 20 planar superconducting coils, which are supported by a massive central support structure. All superconducting coils have been subjected to gravity and electromagnetic force due to the interaction between self-field and the coil current in the test conditions in Saclay, France. Each coil is equipped with a few mechanical sensors. Some of the sensors have indicated considerable deviation from the numerical prediction. The nonplanar coil Type 1 is an example of such deviations. This technical note presents structural analyses performed to verify the numerical modeling by checking the stresses in the measurement points. In order to find the reason from the finite element model, three factors are considered: mesh refinement, increasing the region of mesh refinement, and changing the element supports. The results show that the three factors have no impact on the stresses at the measurement points. Finally, special attention has been paid to the sensors during commissioning of the W7-X, which revealed that lack of information about boundary conditions or temperature fluctuations could be the reason for the original discrepancies.
Shanwen Zhang; Yuntao Song; Zhongwei Wang; Xuebing Peng; Jianfeng Zhang; Yongfa Qin; Linlin Tang; Qiang He. Structural Analysis of Wendelstein 7-X Nonplanar Coil Type 1 in Self-Field Test Conditions. Fusion Science and Technology 2017, 73, 43 -49.
AMA StyleShanwen Zhang, Yuntao Song, Zhongwei Wang, Xuebing Peng, Jianfeng Zhang, Yongfa Qin, Linlin Tang, Qiang He. Structural Analysis of Wendelstein 7-X Nonplanar Coil Type 1 in Self-Field Test Conditions. Fusion Science and Technology. 2017; 73 (1):43-49.
Chicago/Turabian StyleShanwen Zhang; Yuntao Song; Zhongwei Wang; Xuebing Peng; Jianfeng Zhang; Yongfa Qin; Linlin Tang; Qiang He. 2017. "Structural Analysis of Wendelstein 7-X Nonplanar Coil Type 1 in Self-Field Test Conditions." Fusion Science and Technology 73, no. 1: 43-49.