bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the body type of shaft spillway
Authors: Yang Shaojia , Liu Xiaoyu , Wang Jinfeng , Zhu Hongbo 
Published: July 2024

Abstract
In this paper, the influence of shaft spillway shape on its performance is studied by numerical simulation to improve its design and operation efficiency. The type of pressure slope section, the sensitivity of the radius of the turning section, and the optimal arrangement of the stilling pool are studied and analyzed. It is found that increasing the length of the pressure slope section can stabilize the flow in the pressure section of the tunnel. The deflection phenomenon can be reduced by increasing the radius of the turning section. The symmetrical arrangement of the stilling pool can improve the water flow pattern. Through numerical simulation, the paper provides some suggestions on the optimal design of the shaft spillway to improve its performance and efficiency.
Optimization of deep acid fracturing parameters for Shunbei carbonate dissolved fault reservoirs
Authors: Chao Xunsheng , Guan Chencheng , Xin Shunyuan , Ren Jichuan , Xu Peixuan 
Published: July 2024

Abstract
When encountering favorable reservoirs that have not been drilled along the wellbore trajectory of Shunbei carbonate fracture-cavity reservoirs, deep acid fracturing technology is required to communicate with favorable reservoirs and achieve production. Currently, there is no optimized method for designing deep acid fracturing parameters for Shunbei fracture-cavity reservoirs, which results in problems such as failure to communicate with favorable reservoirs after deep acid fracturing or rapid decline in production after communication. To address these issues, this paper establishes a geological feature model for fracture-cavity reservoirs based on the characteristics of Shunbei fracture-cavity reservoirs and proposes a deep acid fracturing fracture parameter optimization approach with production capacity as the goal. Using a multi-field coupled acid fracturing model that can reflect the large leakage characteristics of fracture-cavity reservoirs, the proposed fracture parameters are used to simulate and optimize the scale of pre-flushing liquid and acid liquid. The simulation results show that the desired increase in production can be achieved when the fracture diversion capacity is 30D·cm and the penetration ratio is between 0.1 and 0.3. Furthermore, this paper recommends injecting 450~900 m3 of pre-flushing liquid to communicate with favorable reservoirs (0.1≤De≤0.2), followed by the injection of 900 m3 of cross-linked acid and 450 m3 of gelled acid to construct the fracture diversion capacity through acid corrosion.
Numerical simulation analysis of the influence of karst cave orientation and surrounding rock properties on tunnel excavation
Authors: Tao Xinhua , Gan Fan , Yu Jiang , Huang Linchong , Chen Yu 
Published: July 2024

Abstract
The underground distribution of complex karst geology in the Zhangjiajie region of China poses a significant threat to the construction safety of tunnels, not only increasing project investments but also severely impacting the stable operation of engineering construction. This paper, based on ABAQUS numerical simulation, explores the influence of karst caves around tunnels in different orientations of surrounding rock environments through the rock strength, stress field, and dimension of surrounding rock mass. The results are as follows: (1) With the decrease in cohesive strength of the cave surrounding rock, the stability of the tunnel is enhanced. (2) The maximum displacement of the lower cave is 0.02011 m, greater than that of the side cave, which is 0.01965 m; the maximum principal stress of the lower cave is 7.457 MPa, greater than that of the side cave, which is 7.423 MPa. The lower cave has a greater impact on tunnel construction and can further reduce the stability of the karst tunnel surrounding rock. This paper has researched the influence of caves on tunneling through surrounding rock and investigated the effects of cave orientation, cohesive strength, and other parameters on tunnel construction. It provides theoretical guidance for tunnel alignment and pre-processing of concealed caves.
Study on the spectrum model of light response of Manglietia yuyuanensis
Authors: Guo Jian , Guo Yong , Wang Hong , Huang Chenying , Lin Huoyang 
Published: July 2024

Abstract
To study the spectral characteristics of the photosynthetic response of Manglietia yuyuanensis, this paper uses a self-developed monochromatic light generator to generate 22 kinds of monochromatic light, and measures the net photosynthetic rate of Manglietia yuyuanensis under the irradiation of 22 kinds of monochromatic light, then obtains its light response curve under different wavelengths. The right-angle hyperbolic correction model was used to fit the light response curves under each kind of monochromatic light, and the completed spectrum of the light saturation points of Manglietia yuyuanensis was obtained. It makes up for the disadvantage that the self-developed monochromatic light generator cannot detect the light saturation point of the plant under some monochromatic light due to the low radiation intensity. This paper supposes that the coefficients α, β, γ, and Rd in the right-angle hyperbolic correction model are functions related to the wavelength λ, then fits a Gaussian function of α, β, γ, and Rd to wavelength λ. From the fitting results, the fitting degree of α, β, and γ can reach 0.8 or more, which indicates the fitting effect is good. The fitting degree of Rd is about 0.5. According to the fitting function, a new photosynthesis model related to wavelength and light radiation was obtained, and the fitting degree of the data by the new model is good, laying a foundation for future research on photosynthetic response curves of other plants.
Study on applicability of mathematical model of pipe-soil interaction
Authors: Hou Yu , Liu Yuqing , Sun Chao , Zhang Zhenyong , Kong Tianwei , Wu Xiatong , Yang Zhaohan , Huang Wei , Liu Xiaoben 
Published: July 2024

Abstract
The applicability of the soil spring calculation model given in China’s standard SY/T 7403 “Code for strain-based design of oil & gas transmission pipelines” and GB/T 50470 “Seismic technical code for oil and gas transmission pipeline engineering” to large-diameter pipelines is not clear. In this paper, the soil spring calculation formulas recommended in the two standards are analyzed, and the corresponding finite element numerical simulation models are established. The applicability of the lateral and vertical soil spring models in the two standards is discussed. The results show that the calculation accuracy of the two standards needs to be improved, and the applicability is different for different pipe diameters and soil properties.
Study on the influence of selective laser melting temperature on the melting bath
Authors: Luo Wei , Hui Jizhuang , Wang Junjie , Yan Zhiqiang 
Published: July 2024

Abstract
The high-temperature gradient and high-frequency thermal cycling during the selective laser melting process will seriously affect the melting bath morphology and dimensions, which in turn affects the quality of formed parts. In this paper, a numerical model of the SLM process is established to emulate the temperature field and investigate temperature variation of single-layer and multi-channel models, as well as the influence of disparate laser power, hatch spacing, and scanning speed on melting baths. The simulation results show that the temperature gradient at the front end of the melting bath is small due to physical phase transition, and the temperature gradient nearer to the end of the melting bath is bigger. The midpoint of the second melting channel has the highest peak temperature due to heat conduction and accumulation; the impact of each technological parameter on the melting bath is in the following order: laser power > scanning speed > hatch spacing. Therefore, it is clear that the temperature distribution will provide a theoretical foundation for regulating the stress state of molded parts and ensuring the surface quality and mechanical capacity of the processed component.
Establishment and analysis of a unified mathematical model of kinematics and dynamics of flexible parallel mechanisms
Authors: Wang Jin , Jing Zijian , Guo Junli , Qin Tao , Li Han , Li Xin , Li Zhenchuang , Meng Fanhui , Qi Bo 
Published: July 2024

Abstract
The conventional positive solution approach for determining the forward motion of the kinematic mechanism relies primarily on the outcomes of the inverse solution of motion, which is not universally applicable to flexible parallel mechanisms. Furthermore, the process of analyzing the natural frequency of parallel mechanisms is complex, cumbersome, and challenging. More importantly, the two models are independent, and there is no unified mathematical analysis model for flexible parallel mechanisms. Therefore, this paper establishes a unified mathematical model for kinematics and dynamics analysis of flexible parallel mechanisms through an improved multi-body system transfer matrix method. Taking the flexible 3-RPU planar mechanism and the space 2-RPU (2-UPS) space mechanism as examples, respectively, the forward motion solution of the mechanism was analyzed and its working space range and resonance frequency were solved. Finally, the calculation results are compared with the simulation results, and the feasibility and accuracy of the method are proved. Through this method, we can quickly solve the motion characteristics of the mechanism without relying on the results of the inverse solution of the mechanism, which provides suggestions for the precise control of flexible parallel mechanisms and also provides corresponding reference basis for the practical application of flexible parallel mechanisms.
Numerical simulation of the effects of toothed structure on the flow boiling characteristics of micro-fin tubes
Authors: Lu Yongshuai , Cui Yunfang 
Published: July 2024

Abstract
The numerical simulation of R141b flow boiling in micro-fin tubes (MFTs) with a 1 mm equivalent diameter is conducted using the VOF and the Lee models. An analysis of the boiling heat transfer (HT) characteristics has been performed, considering impacts of the four factors. The most suitable correlation of boiling HT has also been evaluated. The summarized findings are as follows: the BHT coefficient within the MFTs consistently rises with increased mass velocity, heat flux, and saturation temperature. However, there is a presence of a partially dry-out region inside the MFTs at high heat flux. Additionally, the enhancement of boiling HT by elevating saturation temperature is not prominent in the low vapor quality range. HT coefficients of the MFTs with various fin structures ranked in magnitude are as follows: tapered MFTs > trapezoidal MFTs > circular MFTs. The model proposed by Wu is identified as the best predictor for flow boiling HT performance in horizontal MFTs, although its prediction accuracy is limited in the low vapor quality range.
Numerical simulation of control rod ejection velocity in a projectile rod accident based on STAR-CCM+
Authors: Kong Fanfu , Cai Ruhua , Luo Qingsong , Li Shujie , Xu Huaijin 
Published: July 2024

Abstract
To simulate and analyze the control rod ejection time in the process of reactor bomb rod accidents, the design input of bomb rod accident safety analysis is made. In this study, STAR-CCM+ simulation software was used to simulate the pressure field and velocity field in the process of high temperature and high-pressure liquid injection after the CRDM pressure casing was broken, and the ejection time of the control rod under different lifting forces was obtained comprehensively. At the same time, the simulation results are compared with the theoretical calculation results. The pop-out time of the control rod is about 0.1 s. Therefore, the results calculated by the simulation model established in this study can be used as the design input for the safety analysis of the projectile rod accident.
Theoretical and simulation study on the vibration modes of shear walls in prefabricated modular construction
Authors: Kong Va , Wang Xiaoguang , Wang Qiong , Li Zhen , Chen Hongbing , Wang Jiang 
Published: July 2024

Abstract
As prefabricated construction advances, the enhanced informatization and the industrialized modular construction method of MIC (Modular integrated construction) shear walls have been widely applied in real projects. MIC shear walls are generally made up of prefabricated wall modules with varying strength grades, using concrete of various ages, and are combined with cast-in-place concrete. Due to the unique construction requirements of these walls, defects such as interfacial delamination and internal voids might occur, arising from factors like concrete shrinkage and creep, complex interfacial structures, inadequate compaction during vibration, and construction process issues. Since these interfacial defects cannot be visually inspected from the exterior, developing non-destructive testing (NDT) methods specifically for detecting such defects in shear walls becomes an urgent necessity. This paper utilizes a combination of theoretical analysis and numerical simulation to explore the vibration modes of MIC shear walls with hidden defects. First, a theoretical model is proposed for the local vibration modes of MIC shear wall shells with consideration of interfacial delamination defects. Then, a numerical simulation model is established based on MIC shear wall construction and defect features to simulate the vibration behavior accurately. Finally, after examining the theoretical and simulated vibration characteristics of MIC shear walls, a significant theoretical foundation is established for identifying interfacial defects in MIC shear walls.
Study on the sound radiation characteristics of polygonal wear wheels of CRH3 high-speed train
Authors: Zhang Yaning , Zhang Xiaoan 
Published: July 2024

Abstract
Due to the increase in train operating speed, the phenomenon of collision vibration between wheels and rails becomes more and more obvious, and the degree of wheel wear increases dramatically. As a result, the wheel-rail noise problem has become more and more complex. The wheel polygonal wear is also widespread on the train. For the wheel in the form of polygonal wear of the wheel-rail vertical force, combined with the principle of wheel-rail noise, we conduct an in-depth study. An aerodynamic mutual coupling model for CRH3 high-speed vehicles is proposed. The role of the amplitude of 0.03 mm, i.e., the twentieth-order polygonal abrasion rate on the wheel-rail force is analyzed at the speed class of 200~350 km/h, and the acoustic radiation characteristics of the wheels are investigated at different speed classes. The results show that under different speed classes, when the wheel polygon order is in the twentieth order, the wheel-rail vertical force rises with the increase of speed, and the wheel sound power is also affected by a great change. There is a significant increase in the sound power from the low frequency of 20 Hz to 100 Hz and a peak in the mid-frequency up to 1, 000 Hz. Secondly, when the wheel radiated sound pressure levels at different speed levels, significant changes also occurred, with the sound pressure reaching a maximum of 110 dB at 350 km/h.
Design and implementation of a collaborative modeling architecture based on MDE (Multi-DDS Edge)
Authors: Zhang Songning , Guan Zheng , Ci Yan , Ding Gangyi 
Published: July 2024

Abstract
Virtual space is an integral part of the Metaverse. Typical virtual spaces are modeled step by step using artificial means. With the development needs of Metaverse modeling and simulation technology and the need for simulation fidelity and content richness in virtual space construction, efficient and correct modeling methods are required. It has become a bottleneck restricting the efficiency of virtual space modeling. This paper designs a multi-person collaborative virtual space modeling method, which improves the modeling efficiency, communication security, and interaction stability of the virtual space collaborative modeling method. Compared with existing collaborative modeling methods, this paper proposes a virtual space collaborative modeling method based on multi-edge DDS technology. By constructing MDE (multi-DDS edges) and MDE on user migration, collaborative construction in multiple virtual spaces is completed. Model data communication extends collaborative modeling technology from the virtual space creation stage to the virtual space simulation and deduction stage, and designs and verifies collaborative content, collaborative architecture, and collaborative communication. Experiments show that the architecture synergy efficiency is 145.6%, the architecture synergy efficiency is 212.5%, and the architecture synergy efficiency is 105.4%. As the number of people in collaborative modeling increases, the operational complexity and demonstration take a logarithmic form, meeting the needs of the future development of the metaverse.
Design and simulation of system to prevent runway overrun during landing of civil aircraft
Authors: Zhang Tao , Wang Xiaorui 
Published: July 2024

Abstract
The airborne runway overrun prevention system predicts landing distance by utilizing real-time aircraft status parameters obtained through onboard sensors. This system offers early warnings to pilots, thereby enhancing flight safety. This paper introduces a design scheme for a runway overrun prevention system considering aircraft dynamic performance. Initially, the study analyzes the basic components and functional requirements of the system based on the Minimum Operational Performance Standard For A Runway Overrun Awareness And Alerting System by the European Aviation Safety Agency. Subsequently, the approach and landing phases are segmented into four stages, providing a methodology for calculating landing distance using a dynamic model. Finally, concluded with a simulation verification conducted on the X-Plane flight simulation platform, we test the visual alarm system of the proposed runway overrun prevention system. Simulation results demonstrate that, during the landing phase, the system dynamically calculates and updates stopping points for each braking mode based on the current braking method. In situations where there is a risk of runway overrun, the system issues timely and well-founded alarms.
Optimization of the deformation transfer mechanism: analysis of spring hanging point and structural parameters
Authors: Lin Zhuoyu , Luo Kai , Zhang Meng , Yang Minghao 
Published: July 2024

Abstract
This paper thoroughly investigates the impact of the spring hanging point’s positioning and structural parameters on the multi-mode robot’s performance within the deformable transfer domain mechanism. The spring hanging point is a pivotal design element, significantly influencing the robot’s extensive deformation, efficiency, and adaptability. Operating as a cross-domain entity between land and air, the robot effectuates the transition between ground and aerial domains via the deformation trans-domain mechanism, executing a spectrum of intricate tasks. The precise placement of the spring hanging point and variations in structural parameters directly shape the robot’s performance metrics, encompassing deformation speed, stability, and energy utilization. Through elucidating fundamental principles, deliberating spring hanging point location choices, suggesting optimization methodologies, scrutinizing structural parameter impact on performance, and validating via dynamic modeling, this paper offers theoretical underpinnings for deforming domain mechanism design and enhancement, thereby elevating the robot’s overall efficacy.
Analysis of structural dynamic response of vertical sound barriers under natural wind and vehicle induced pulsating wind effects
Authors: Wen Duo , Zhang Xiao’an , Yang Li 
Published: July 2024

Abstract
Aiming at the influence of natural wind and vehicle-induced pulsating wind on vertical sound barriers, a finite element plug-in panel sound barrier is established based on the finite element method for dynamic response analysis. This paper establishes a sound barrier finite element analysis model based on finite element analysis software. It takes the 8-span vertical sound barrier as the basic working condition to analyze the dynamic response analysis of the sound barrier structure under the action of natural wind of different grades, i.e., the influence of pressure and displacement; the dynamic response of the sound barrier structure with a natural wind speed of 7 grades or more. In addition, it analyzes the dynamic properties of the sound barrier structure caused by train-induced pulsating wind pressure at speeds of more than 200 km/h, i.e., the influence of pressure and displacement, and investigates the dynamic characteristics of different vehicles with different wind speeds, pressure, and displacement. Furthermore, the response of the vertical sound barrier at different vehicle speeds is also explored, and the results are compared to examine its dynamic response. The research findings show that the sound barrier structure does not resonate during the self-resonance analysis, but the vibration of adjacent sound barrier panels affects each other. As natural wind speeds increase, the displacement of the steel column endpoints of the vertical sound barrier gradually increases; along the length of the sound barrier, the change of the peak pressure at the top of the steel columns and the top of the unit plate shows a symmetrical trend, and the displacements of the steel columns and the top of the unit plate show a trend of gradual increase in the travelling direction, and they both increase at the end of the column. The displacement of the top of the steel column and the top of the unit plate both show a trend of gradual increase along the direction of the vehicle, and both reach the maximum value at the end of the steel column and the unit plate. With the increase in vehicle speed, the overall peak displacement value also increases synchronously.
Design and analysis of sensor structure based on ultrasonic temperature measurement
Authors: Ye Shiqing , Cui Rongxu , Liu Dongjing , Zhang Yangyang , Li Jiahua , Huang Hui 
Published: July 2024

Abstract
Based on the principle of ultrasonic temperature measurement, this paper designs the structure of a waveguide rod sensor with a reflective groove. Using multi-physics field simulation software to conduct acoustic thermal coupling parametric simulation analysis on six different high melting point materials, we obtain the curve functions of the relationship between sound velocity and temperature for the six materials and verify the feasibility of ultrasonic temperature measurement using waveguide rods. Analysis shows that the sensitivity of six alloys to temperature changes is as follows: Ti6Al4V titanium alloy > α-Al2O3 > Inconel693 nickel-based alloy > ThO2 > Tungsten-rhenium alloy > Ta8W2Hf. At the same time, three different shapes of waveguide rods were designed: single groove waveguide rod, multi-zone waveguide rod, and spiral waveguide rod to analyze the impact of temperature measurement accuracy. The research results have important theoretical guidance significance for solving the problem of temperature measurement in high-temperature environments.