bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research and Analysis on the Optimization of the Preventive Disassembly Inspection Intervals of Important Wedge Gate Valves in the Primary Cooling System of CPR1000 Nuclear Power Plant
Authors: Yang Lifei , An Daqi , Li Guangyu , Zhou Jun , You Xiaoyou , Cao Guanghui 
Published: February 2024

Abstract
At present, the important wedge gate valve of the primary coolant system of the CPR1000 nuclear power plant performs preventive disassembly inspection according to the intervals of 5 years, the average dose of a single disassembly is about 10mSv, the average time of each overhaul occupies the critical path is 1 hour, and the valve has been disassembly inspection in good condition. Based on the historical maintenance data, operating environment, failure mode, failure mechanism, operation and maintenance experience feedback of the same type of valve, and failure risk control of the important wedge gate valve of the primary coolant system, this paper demonstrates and analyzes the feasibility of extending the disassembly inspection intervals of the important wedge gate valve of the primary coolant system from 5 years to 10 years. This work plays an important role in improving the economic efficiency of nuclear power plant maintenance and reducing the radiation dose of maintenance.
Experimental Study on Non-contact Labyrinth Seal under Negative Pressure Intervention
Authors: Wu Luji , Sun Yibo , Li Kunlong , Yang Linjie , Chen Junhao , Wang Jingyuan 
Published: February 2024

Abstract
The non-contact labyrinth seal structure of a high-speed gearbox was taken as the research object, a non-contact labyrinth seal structure under negative pressure intervention was designed, and its rationality was verified by simulation analysis. An airfoil-shaped acquisition device for collecting negative pressure was designed, and its rationality was analyzed by simulation. According to the design, a test platform for non-contact labyrinth seal under negative pressure intervention was built to measure the pressure data of each sealing chamber of the non-contact labyrinth seal under different working conditions. The results showed that it was effective to balance the internal and external pressure of the non-contact labyrinth seal by using the negative pressure collected by the airfoil-shaped device in the complex flow field of the high-speed gearbox. It also showed that the non-contact labyrinth seal structure under negative pressure intervention designed in this paper is an effective way to solve the leakage problem of the non-contact labyrinth seal used in high-speed gearbox.
Influence of Shape, Installation and Rotation Motion Errors on Tin Bronze Clearance Seal of Rotary Joint
Authors: Jia Xingyun , Li Kening , Liu Chunrui , Zhang Le , Chen Tao 
Published: February 2024

Abstract
The rotary joint is the key device of the marine clutch. Once the seal fails, the power cannot be transmitted. In view of the above problems, this research studies the influence of shape, installation and rotation motion errors on clearance seal. The results show that compared with the absence of roundness error, the roundness error of the shaft will increase the leakage by about 2.5-4.9 %. The cylindrical error of the bushing will reduce the leakage, but it will bring more serious friction, wear and life problems. The existence of radial installation error will increase the leakage, and the larger the radial installation error, the more obvious the flow field extrusion, the higher the unevenness of the pressure field in the whole flow field. The existence of angular installation error will reduce the leakage, but it will cause more serious friction and wear, resulting in a sharp increase in temperature. The leakage increases by about 0.68 % when the radial installation error is 0.1 mm, and the rotary motion error further increases the leakage by about 0.15 %. The above research can provide theoretical support for the structural design and optimization of the rotary joint tin bronze clearance seal.
Optimization Design of Mining Tri-cone Bit Air Nozzle by CFD
Authors: Yan Lili , Wang Qiaozhu , Tang Jingran , Dong Xuelian , Chen Lusi , Song Runquan 
Published: February 2024

Abstract
Performance of the air nozzle of the mine tri-cone bit directly affects life of bit and rock breaking efficiency. The shape of air nozzle influences performance of mine tri-cone bit. It is necessary to optimize the shape of the air nozzle of tri-cone drill bits. The general specifications of gas mine tri-cone bit were analysed. Working condition and parameters of the air nozzle of the mine tri-cone bit were determined. A three-dimensional model of the air nozzle of the mine tri-cone bit was established. The characteristic geometry and range of air nozzle were determined. The performance index of air nozzle was proposed. An orthogonal experiment table of characteristic geometry of air nozzle was established. The ranking of influence weights of characteristic geometry was obtained. Key characteristic geometry which affects the performance of air nozzle was also obtained. This thesis work helps to improve the working performance of the gas nozzle of the three-cone bit. It can provide some reference ideas for the optimized design of the cone bit
Fracture Failure Analysis of a 5-7/8” Drill Pipe Pin Joint in an Ultra-deep Gas Well
Authors: Ji Nan , Wang Peng , Feng Chun , Zhu Lijuan 
Published: February 2024

Abstract
In recent years, the frequency of drill pipe failure accidents has increased during ultra-deep well drilling process. The fracture failure of pin joint of a 5-7/8” drill pipe happened in an ultra-deep gas well after thirty-five hours’ service. Failure causes were investigated by physical and chemical properties test of the material, macro and micro feature analysis of the fracture surface. The results showed that the physical and chemical properties of the drill pipe were all satified the corresponding standard requirements, the fracture of mode of the dill pipe is fatigue fracture, which was attributed to the harsh load condition during the reaming operation. Furthermore, the increased inner diameter of the pin joint also gives an acceleration of the fatigue fracture process.
Surface Analysis and Optimization of Large Aperture Mirror Supported by Elastic Expansion Sleeves
Authors: Zhang Jinsong , Zhang Zhiming , Fan Quantang 
Published: February 2024

Abstract
In order to meet the stability of the support structure of arrayed large aperture mirror and improve the surface accuracy of the mirror, the elastic expansion sleeve is proposed as the back-support structure of the large aperture mirror. The feasibility of the support method is verified by theoretical analysis and experiment. The PV value of additional wavefront distortion is about 75.3nm<λ/5(λ=632.8nm) when the torque of single mandrel screw is 40N·cm, which meets the technical specifications. The change trend of the support-induced surface is compared between the finite element simulation and the measured results under different mandrel screw torque conditions. When the support torque is increased in equal increments, there is a linear positive correlation between the PV value of support-induced surface and the support torque. Based on the change trend of the support-induced surface, the optimization design scheme of the initial surface is proposed. And the simulation results show that the optimized induced distortion is smaller than that of the ideal surface (the compensation ratio is 7.68%), which reduces the additional wavefront distortion under the actual mounting support.
Creep Analysis and Material Properties Research of Rotary Calciner
Authors: Cheng Yanmei , Zhang Hua , Ye Guoan , Hong Ye 
Published: February 2024

Abstract
Unavoidably, during the aqueous reprocessing of spent fuel, high level liquid waste is produced, which is typically vitrified. A rotary calciner is an essential component of a two-step cold crucible melter equipment system. Owing to the calciner’s long-term operation under high temperature condition, potential effects from metal creep are essential design factors. Stable temperature and stress fields of components of a rotary calciner have been calculated based on the finite element analysis software ANSYS. Furthermore, creep life of creep effects has been evaluated and comparisons among Inconel 690, Inconel625, and SUS 310s tubes’ mechanical property performance have been conducted. The results indicate that all three materials require the mechanical property requirements and SUS 310s exhibits the minimum creep displacement.
Test Data Evaluation of Very High Cycle Fatigue Based on Maximum Likelihood Method
Authors: Zhang Ying , Zhang Chengcheng , Sun Kai , Xu Heming 
Published: February 2024

Abstract
The very high cycle fatigue tests of TC4 alloy were accomplished through ultrasonic fatigue experiment which were conducted on the ultrasonic fatigue testing system at frequency range of 20000 ±1000 Hz. In contrast to the commonly used Basquin model, a Maximum Likelihood Method to fit the three-parameter nonlinear model was used to verify the adaptability in very high cycle fatigue regime. These two methods were used to estimate S-N curves of three types of materials which were TC4 alloy, GH4169 alloy and TC17 alloy in the very high cycle fatigue regime and the results were compared with test data. The evaluation result of the MLM model based on the three-parameter nonlinear model shows a good agreement with test data. The mean and variance of relative error of the MLM model are less than those of the Basquin model, providing a suitable evaluation method for predicting very high cycle fatigue limit which often has higher scatter.
Physical Simulation of Medium and Low Temperature Rolling of Mg-Li Alloy Sheet
Authors: Fu Yida , Li Jun , Li Jiacheng , Peng Weijian , Hu Shuhua , Liu Junwei 
Published: February 2024

Abstract
In this paper, LZ91 magnesium-lithium alloy was taken as the research object. At the rolling temperature of room temperature and 453 K, the plane strain compression physical simulation experiment was carried out on the sample with one pass reduction of 15 % and three passes total reduction of 45 %. After each pass of rolling, the sample was annealed at 503 K for 30 min. Then the effects of different treatment processes on the microstructure of LZ91 magnesium-lithium alloy were studied by metallographic microscope, X-ray diffractometer and scanning electron microscope. The results show that under the same strain, the stress of room temperature rolling is larger than that of 453 K rolling; with the increase of annealing passes, the effect of work hardening gradually weakened. With the increase of rolling amount, the original mechanically mixed ' α ' phase and ' β ' phase will deform along the deformation direction, showing a streamline shape. Rolling at 453 K, the diffraction peak of the sample with 45 % total reduction of three passes changes the most.
A Novel Coupled State/Load/Parameter Identification Method Based on the Improved Particle Filter Algorithm
Authors: Wang Ting , Wan Zhimin , Xie Xuefei 
Published: February 2024

AbstractThere have been increasing research studies focusing on the identification of structural load with uncertain model in recent years. This paper presents a novel approach based on the improved Particle Filter (PF) algorithm for the nonlinear structural system. The main strategy of the approach is the fusion of the weighted least-square algorithm and the conventional PF algorithm. The weighted least-square algorithm is derived for the estimation of the unknown loads, and the PF algorithm is used for the identification of the augmented states which includes the structural displacement, velocity and unknown parameters. Additionally, the parallel algorithm is adopted for the improvement of computing speed, and a resampling step is also used for alleviating the degeneracy of the particles to improve the accuracy. A numerical example modelling as a four-story hysteretic shear-beam building is studied to validate the capability of the presented approach.
A Model Based on CNN-LSTM for the Remaining Life Prediction of Equipment in Aircraft Assembly Pulsation Production Line
Authors: Liu Xiongying , Xiao Junjie , Wang Hongfeng , Zhao Zizhao , Liang Biao 
Published: February 2024

AbstractThe aircraft assembly pulsation production line is an advanced and efficient assembly method widely used in aircraft manufacturing. However, equipment malfunctions would occur and can disrupt production takt, affecting the production efficiency. Therefore, accurately predicting the remaining useful life (RUL) of equipment is very crucial. To meet the requirements of both prediction accuracy and efficiency for RUL model used in aircraft pulsation production line, this work proposed a model combining convolutional neural network (CNN) and long short-term memory (LSTM) for RUL prediction. Optimization was performed for the number of neurons in the proposed model with genetic algorithm (GA) to regulate the prediction accuracy and efficiency. Two public datasets representing typical equipment in the pulsation production line were used to validate the proposed model. The results show that the proposed model outperforms the traditional model with substantial improvements in the fitness function of 19.8%, and 30.2% for the two testing datasets. These findings demonstrate the effectiveness of the proposed model in enhancing the accuracy and efficiency of RUL prediction.
Experimental Study on the Quantitative Relationship between the Non-contact Magnetic Signal and Detection Height of Ferromagnetic Pipelines
Authors: He Tengjiao , Tang Jing , Liao Jun , Chen Lujie , Tang Jian , Xia Guoqiang 
Published: February 2024

Abstract
The non-contact magnetic detection technology has good application prospects in the detection of buried steel pipelines. However, the variation of non-contact magnetic signal and measured height is unknown. The application of the technology in pipeline burial inspection is restricted. Therefore, this article conducts non-contact magnetic signal experimental testing on full-size steel pipelines. The collection method, pipe diameter, internal pressure, measurement height, and the non-contact magnetic signal are quantitatively analyzed. And the propagation factor f
G was defined to quantify the degree of influence of measurement height on the non-contact magnetic signal. The results indicate that when the measurement height increases from 0.1 m to 2.0 m, the variation amplitude of the magnetic gradient modulus obtained by the parallel acquisition method is the largest, with a change rate of - 0.35. The amplitude and linear rate of change of the propagation factor f
G increase with the pipe diameter and internal pressure. The amplitude and linear rate of change of the propagation factor f
G increase with the pipe diameter and internal pressure. In the range of pipe diameters from 355.6 mm to 1016 mm, the amplitude of f
G variation is 0.53, and the rate of change is 0.26. Furthermore, the amplitude of f
G change due to a unit increase in internal pressure is 0.022, with a corresponding rate of change of 0.0114.
Optimization Analysis of the Wheel Hub Dynamic Balancing Machine Based on Particle Swarm Optimization
Authors: Cao Juan , Cao Yuan 
Published: February 2024

Abstract
The vibration supporting rod of a wheel hub dynamic balancing machine is affected by the alternating dynamic load, and its vibration characteristics have a direct impact on the accuracy of measurements. To solve this problem, first, a particle swarm optimization algorithm (PSO) algorithm is proposed to optimize the dynamic stiffness of the vibration supporting rod. According to the actual material selection, the creep risk of the rod is reduced. Second, three schemes for improving the structure of hub balancing machines are put forward and compared. The displacement response and stress response of scheme A are increased by 30% and 20%, respectively, over those of the original equipment. The displacement response and stress response of scheme C are increased by 31% and 22%, respectively, which is a significant improvement. Schemes A and C are acceptable, but a strong first-mode response remains due to assembly variation.
Simulation Study on the Performance of Ultrasonic Pulse-Echo Detector for Ice Thickness Identification
Authors: Zhang Yanxin , Zhang Hongjian , Liu Yifan , Xiong Jianjun , Zhao Zhao , Ran Lin , Yi Xian 
Published: February 2024

Abstract
In-flight icing detectors are important for the flight safety of aircraft. Detectors based on ultrasonic pulse-echo can be used for detecting ice thickness. To study the influencing factors of ultrasonic pulse-echo detection performance, a simulation model of elastic wave-piezoelectric coupling was established, which was used to analyze the influence of different types of piezoelectric ceramics, matching layers with different acoustic impedances, and different substrate materials on ultrasonic pulse-echo signals. It was found that when aluminum is used as the substrate material, the ultrasonic echo signal has a higher signal-to-noise ratio. Furthermore, the influence of aluminum substrate materials with different thicknesses on ultrasonic pulse-echo was analyzed. The ice thickness can be identified by measuring the time of flight between the aluminum-ice interface echo and the ice-air interface echo. The results indicate that when the thickness of the aluminum substrate is 25mm, the upper detection limit of ice layer thickness can reach about 10mm. Therefore, the detection upper limit of ice layer thickness can be extended by appropriately increasing the thickness of the aluminum substrate material.
Inclination Build Rate of a Point-The-Bit Rotary-Steerable Tool
Authors: Wang Shuangning , Tang Ming , He Shiming , Ye Han 
Published: February 2024

Abstract
The combination of a rotary-steerable system (RSS) and power screws has become the main drilling tool for the efficient exploration and development of unconventional oil and gas. However, the application of point-the-bit (POB) rotary-steerable tools in directional drilling subjects spindle bearings to continuous alternating stress, which can lead to fatigue failure. In this study, numerical analysis and simulation are employed to guide the engineering application of rotary-steerable tools, particularly in the field of oil and gas exploitation. The structural composition and steering principles of rotary-steerable tools are analyzed. The influence of the structural parameters of the spindle on the deflection capacity of the tool is analyzed, and the optimal structural parameters are selected. Based on the results, the recommended distances between the various components of the tool could be obtained. Moreover, the maximum deflection capacity increases with torque when the WOB (weight-on-bit) is constant. Similarly, at constant torque, the maximum deflection capacity increases with the WOB. Overall, the WOB has a greater influence on the maximum deflection capacity than torque. To ensure the safe operation of the spindle, the WOB and torque must be within 200 kN and 20 kN·m, respectively. The findings of this study provide valuable insights into the safe application of POB rotary-steerable tools.
Vibration Response Analysis of a Time-varying Stiffness Wheel with Contrate Gear under Unbalanced Excitation
Authors: Xue Beirao , Man Jixin , Zuo Yanfeng , Yan Wengao 
Published: February 2024

Abstract
The vibration and response of multi-contact interface micro-motion time-varying stiffness wheel are analyzed, and the nonlinear vibration response characteristics caused by the unbalance force of multi-contact interface contrate gear face of a gas turbine rotor are studied. Firstly, the local sliding model of dry friction-damped contact is extended to establish a holistic and local unified sliding model. The equivalent stiffness and damping of the damping device are calculated by means of the equivalent linearization method and the first harmonic balance method. Finally, the finite element model of multi-contact contrate gear rotor wheel is established to analyze the influence of different unbalanced masses on vibration response under nonlinear frictional contact. The results show that the response caused by the unbalance mass of multi-contact interface wheel with contrate gear is mainly radial response, and the peak value of resonance response increases with the increase of unbalance force.
Research on Icing Classification Method Based on Wind Tunnel Test with Double Impact Surface Probe
Authors: Liu Wenfeng , Huang Xiong , Ge Junfeng , Luo Huan 
Published: February 2024

Abstract
Facing supercooled large water droplet environment, an effective ice detection method is a prerequisite to implement the avoidance strategy and get out of the icing environment of SLD as soon as possible. Fiber-optic icing sensors were arranged on the double impact surface probe. The probe was used for icing wind tunnel test. Different machine learning algorithms were used to establish the classification method of icing conditions based on multi-sensor ice thickness information fusion. An appropriate algorithm was selected for the classification method to detect icing conditions. The icing classification method based on SVM could effectively distinguish the conventional water droplet icing condition from the SLD icing condition, and it has significant potential on aviation industry application.
Research on Vibration Response of Shrouded Blades Based on Contact State
Authors: Man Jixin , Xue Beirao , Bian Xiangde 
Published: February 2024

Abstract
The shrouded is widely used in vibration reduction of turbine blades. In this study, the damping characteristics of the shrouded blade in gas turbine were studied. Firstly, a finite element model of the shrouded blade was established, and the full set of blades was reduced to a single sector based on the principle of cyclic symmetry. The contact state of the contact surface of the blade at different interference and speeds was calculated based on the displacement extraction method. Secondly, a microslip friction contact model was established based on the contact state of the contact surface. The nonlinear vibration response of shrouded blades was calculated based on the harmonic balance method. The results indicate that the shrouded has excellent vibration reduction performance. The interference and rotational speed of the blade will affect the damping efficiency.
The Crack Generation Algorithm of Underwater Bridge Based on Improved Generative Adversarial Network
Authors: Gu Yeyang , Yin Ling , Chen Haifeng , Song Jialei , Zhang Fei 
Published: February 2024

Abstract
To address the challenge of obtaining underwater bridge crack images for bridge defect detection, this paper proposes an enhanced CycleGAN algorithm based on a generative adversarial network. Within the encoder-decoder architecture, two key enhancements have been introduced. First, to prevent the loss of information at different scales during training, residual connections with 1x1 convolutional kernels have been added. Second, to prioritize useful feature information during model training, the CBAM attention mechanism has been incorporated. Experimental results demonstrate that the improved model significantly enhances performance, with a 29% increase in the FID index, as well as a 9% improvement in PSNR and a 7% improvement in SSIM.