bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity analysis of influencing factors in large oscillation hydraulic transient process of pumped storage power station
Authors: Liu Tao , Hu Tengyao , Yuan Yanliang , Tang Lei , Wang Hongqing 
Published: June 2024

Abstract
The calculation of large oscillation transition process is of great significance for pumped storage power station, which is beneficial for ensuring the safe of the power station and extending the lifespan of the unit. Due to the presence of inertia in water and rotating components of the unit, as well as energy imbalance in the system, hydraulic transients will cause drastic changes in water pressure in the waterway system and unit speed, resulting in a sharp increase or decrease in pressure and a sharp change in unit speed, endangering the operational safety of the power plant and affecting the lifespan of the unit. It is necessary to optimize the layout of water conveyance system, basic parameters of units, and the closing law of guide vanes through calculation and analysis of large oscillation transition processes. Relying on a pumped storage power station in Guizhou, this paper analysis the sensitivity of the factors affecting the calculation results of the large oscillation transition process, such as runner characteristics, guide vane closing law, moment of inertia GD2, surge chamber diameter and restricted orifice size, to provide reference for similar projects.
Molecular dynamics simulation of C4F7N/CO2 mixed insulating gas
Authors: Zu Hongpeng , Lin Xin , Chen Kai 
Published: June 2024

Abstract
The substitution of SF6 in gas-insulated electrical equipment has become a hot issue in the electrical field, and the research on the green medium C4F7N and its gas mixture has attracted much attention. In this paper, the molecular dynamics simulation method was used to analyze the C4F7N and CO2 mixed insulating gas system in situ, and quantitatively simulate the concentration distribution, root mean square displacement, intermolecular interactions, and thermodynamic parameters of the insulating gases under the macroscopic conditions of different mixing ratios, pressures, and so on. The results show that by increasing the proportion of C4F7N at 298 K and 0.6 MPa, the mutual attraction between C4F7N and CO2 molecules is enhanced, which leads to the decrease of the diffusion rate of the two gases, and the gas distribution is uniform without obvious delamination phenomenon, which reflects the good compatibility. At the same time, the increase of the mixing ratio of C4F7N increased the adiabatic and isothermal compression coefficient of the gas mixture at 0.6~0.8 MPa accordingly, and the gas mixture did not show liquefaction phenomenon. This study provides a certain basis for designing the mixedinsulating gas ratios to meet engineering needs.
Verification and evaluation methods for pipeline leak detection algorithms
Authors: Chang Lingzhi , Fan Shidong 
Published: June 2024

Abstract
As an important equipment in energy transportation and utilization, state detection is a key link to ensure the safety and environmental protection of the equipment. At present, there are many types of pipeline leakage detection algorithms, but there is less verification and evaluation of the actual performance and characteristics of the algorithm. Therefore, based on the evaluation index system, the entropy weight method (EWM), and the TOPSIS, we build a pipeline leakage inspection evaluation model of the measurement algorithm. In addition, the actual liquid pipeline transportation experiment platform is established. The negative pressure wave method is selected and combined with the CNN-LSTM algorithms to perform experiments. The results show that the algorithm used in this paper is better than the traditional negative pressure wave algorithm (NPW). The performance and calculation results can provide a reference for scientific research, engineering, teaching, etc.
Numerical investigation on the energy extraction characteristics of parallel multi foils arranged in columns
Authors: Wang Yulu , Liu Tianyuan , Guo Kailun 
Published: June 2024

Abstract
The oscillating foil is a focus device in the clean energy utilization field. The presence of an oscillating foil structure within the flow field significantly impacts the energy extraction capabilities of the system. In this paper, three types of parallel multi-foil structures arranged in columns are proposed. The energy extraction characteristics of diverse multi-foil structures under various oscillation conditions are analyzed numerically. The flow field structure and the impact of parallel multi foils on the aerodynamic characteristics are investigated. Results demonstrate that the multi-foil structure with a phase difference of 180° achieves the highest level of energy extraction performance, and the maximal mean power coefficient achieves 0.894, which is 11.03% higher than that of the structure with a smaller phase difference. The size of the trailing edge vortex under the structure with a phase difference of 180° is significantly larger, leading to an obvious fluctuation in the aerodynamic lift.
Design of a mining carbon monoxide sensor and analysis of multi-gas cross-interference performance
Authors: Zhao Qingchuan , Liang Guangqing 
Published: June 2024

Abstract
A new type of carbon monoxide sensor is designed to address the issue of cross interference of nitrogen oxide gas in the exhaust emissions of underground diesel engine rubber-tired vehicles with electrochemical carbon monoxide sensors, which leads to frequent false alarm accidents. The hardware circuit design of the DC-DC voltage reduction power supply circuit, display circuit, component signal processing circuit, etc. is detailed, At the same time, the sensitive components used in the sensor adopt a special gas filtration membrane design. Six types of gases, including hydrogen sulfide, nitric oxide, nitrogen dioxide, hydrogen, ethylene, and acetylene, were sequentially introduced in the laboratory for experimental analysis of multi-gas cross-interference performance. The experimental results have shown that the new carbon monoxide sensor can filter out nitrogen oxide gas, thereby solving the impact of underground rubber tire vehicle exhaust on the accuracy of carbon monoxide gas detection. It has broad prospects for promotion and application in coal mines underground.
Investigation of resistance performance of anti-icing wave-plate separators for marine gas turbines intake system
Authors: Deng Zhiwei , Wang Zhongyi , Chen Xiaohu , Ma Wenqi 
Published: June 2024

Abstract
Due to their high power and efficiency, gas turbines are commonly used propulsion systems in hovercraft propulsion systems. In polar and cold marine environments, when a hovercraft rises, a significant number of droplets are generated on the water surface and are drawn into the gas turbine’s air intake with the cold air. This paper takes the structure of the original wave-plate separator as a reference and designs two structures: the rhombic anti-icing wave-plate separator (RAWS) and the streamlined anti-icing wave-plate separator (SAWS). Experimental and numerical simulation methods are employed to calculate the air intake resistance of the two structures at speeds ranging from 1 to 10 m/s. The results show that the K-ε standard enhanced wall function turbulent model is the closest to experimental measurements, with all calculated results having an error below 5%, demonstrating reliability. Compared to RAWS, the calculated total pressure loss for the SAWS structure decreases by 200 Pa under a designed air intake velocity of 7 m/s, representing a relative reduction of 40.8%. This provides a valuable reference for the design and resistance optimization of ship air intake anti-icing devices.
Study on evaporative condensation and heat and mass transfer characteristics of the second refrigerant in calorimeter
Authors: Zhou Kun , Zheng Mingyu , Xie Baogang , Yu Xiaolin , Xie Hongxi , Fu Wei , Shen Pengfei 
Published: June 2024

Abstract
A simulation study was conducted to explore the evaporative condensation and heat/mass transfer characteristics of the second refrigerant within the calorimeter. The objective was to establish both physical and mathematical models for the second refrigerant and to perform numerical simulations of the pressure and temperature fields within the calorimeter. The second refrigerant in the calorimeter was modeled physically and mathematically, and the pressure and temperature fields within the calorimeter were studied through numerical simulation. The findings indicate that with the input of electric heating power in the calorimeter, the pressure gradually rises alongside the temperature of the second refrigerant, leading to evaporation. Owing to the low surface temperature of the evaporation coil, the evaporated refrigerant vapor condenses on its surface, resulting in a decrease in temperature around the coil. The uneven distribution of temperature contributes to varying heat transfer rates across different areas of the calorimeter shell.x
Computational boundary improvement and performance optimization of the flue gas waste heat cascade utilization system of the ultra-supercritical 1000 MW generator set
Authors: Wang Xinyuan , Wang Dongqing , Wang Zeming , Shi Yuetao 
Published: June 2024

Abstract
There is no uniform performance test rule and standard calculation method for efficiency improvement of a system that utilizes waste heat from flue gas and it is mainly carried out through turbine parameters, without considering boiler system performance. Given the above problem, in this paper, the steam turbine, boiler and waste heat from the flue gas step-up utilization system are calculated by establishing a thermal model of ultra-supercritical secondary reheating 1000 MW unit. At the same time, unit design data and field performance test results are used for verification. Analysis comparing simulation outcomes with experimental data revealed that the discrepancies in the heat consumption rate per unit, the efficiency of the boiler, and the rate of coal consumption for power generation peaked at a marginal variance of 0.2%. The optimum operating parameters of the system for low-grade flue gas recovery in a cascading manner are obtained through variable operating condition calculations. The optimum value of high-pressure bypass feed-water flow rate is 52 kg/s at 970 MW operating condition. At the same time, the difference between high-pressure bypass effluent and high plus effluent temperatures should be controlled to be close to 0°C, and the optimal value of low-pressure bypass condensate flow rate is 53 kg/s. As the flow of flue gas in the bypass increases, the efficiency of heat exchange in the bypass economizer also increases, resulting in greater absorption of heat in the utilization apparatus for flue gas waste heat, leading to a more effective energy-saving outcome. However, it is necessary to regulate the temperature of both the primary and secondary air to levels that exceed the minimum requirements for the safe functioning of the coal mill.
Single pulse lightning and multiple lightning intrusion overvoltage in 500 kV GIS substation
Authors: Zhang Zongyang , Xu Weinian , Li Wenbing , Lu Chen , Chen Zehua , Zhang Sen , Duan Guanghui , Lu Hongbo 
Published: June 2024

Abstract
Lightning intrusion wave is a key factor threatening the safe operation of substations. This paper uses electromagnetic transient simulation software to calculate and analyze the overvoltage characteristics and influencing factors of lightning intrusion waves in GIS substations. It studies the effects of lightning current waveform, corona effect, and multiple lightning strikes on the lightning overvoltage. The results show that with the same amplitude of lightning current, the longer the duration and lower the steepness are, the lower the peak and steepness of lightning overvoltage invading the power station will be. As the distance between the lightning strike point and the substation increases, the attenuation effect of corona on lightning overvoltage shows a “not obvious-significant-saturation” pattern. When multiple lightning strikes occur, the peak and steepness of overvoltage caused by the first lightning strike are the highest, and the temperature rise of the lightning arrester varies linearly with the number of lightning strikes.
Research on wind farm power forecasting based on IGWO-CNN
Authors: Yin Yi , Wang Jiahan 
Published: June 2024

Abstract
An enhanced convolutional neural network (CNN) has been proposed to address the issue of low accuracy in wind farm power prediction using traditional methods, which leverages an improved version of the Gray Wolf Optimizer (IGWO). The standard Gray Wolf Optimizer (GWO) exhibits a linear change in the search range, which can limit its dynamic convergence capabilities. By incorporating nonlinear convergence factors and dynamic convergence strategies, the improved algorithm modulates the global search pace, effectively preventing it from getting stuck in local optima. The refined IGWO is subsequently applied to fine-tune the optimal CNN architecture, mitigating the uncertainty typically associated with the structural configuration of CNNs. When predicting the actual power measurements from a wind plant in Inner Mongolia, the results indicate that the IGWO-based CNN method outperforms both the conventional GWO-CNN approach and the standalone CNN regarding prediction accuracy.
High-precision substation electric energy metering device based on an adaptive algorithm
Authors: Wang Zhendong , Han Xueyu , Wang Yonggui 
Published: June 2024

Abstract
With the rapid development of science and technology, the structure of new power systems continues to advance, and the requirements for the digitalization and intelligence of power network operation equipment continue to improve. The use of electricity is increasing year by year, and the importance of using a variety of technologies to improve the accuracy of energy metering devices is becoming increasingly prominent. In this paper, a design scheme of a high-precision energy metering device based on an adaptive algorithm is proposed based on the in-depth study of many kinds of current energy metering terminals, in combination with the current detection technology and embedded technology. By improving the accuracy of the electric meter, the accurate measurement of electric energy can be achieved, and the operation ability of the power grid can be improved.
Coordinated operation of PV/EV/Temperature controlled loads in distribution network
Authors: Wang Chenyu , Hu Junjie 
Published: June 2024

Abstract
In order to solve the problems of voltage exceeding limits, local use, and reverse power flow due to the high proportion of distributed photovoltaic grid connections, a distributed photovoltaic uptake method considering demand-side resources and energy storage is proposed. Firstly, based on the equivalent thermal parameter (ETP) method, a load scheduling model for temperature-controlled loads is established. Secondly, with the objective function of minimizing the comprehensive operating cost of the distribution system, combined with the regulating effect of energy storage, stability and safety constraints for the distribution network, as well as the adjustable characteristics of thermal storage electric heating, air conditioning load, and electric vehicles, a demand side optimization model for the distribution network is established, which takes into account voltage safety and distributed photovoltaic uptake. Finally, based on historical data in Fengning County, Chengde City, and a certain park in Tangshan City, simulation analysis was conducted to obtain scheduling schemes and various scheduling indicators for the joint participation of demand-side resources and energy storage in the distributed photovoltaic local use of the distribution network under different permeability. The effectiveness and rationality of the proposed distributed photovoltaic consumption model were verified.
Design of unattended gas pumping station system based on multi-source data fusion
Authors: Wan Yong 
Published: June 2024

Abstract
Aiming at the problems that some data has been built and distributed in different subsystems during the transformation of the unattended system of an underground gas pumping pump station in Shanxi Tiandi Wangpo Coal industry, such as low data sharing and comprehensive utilization rate due to data isolation, and weak linkage execution ability, a method combining site-level data fusion and platform-level data fusion is proposed. The advantages and disadvantages of the fusion method are analyzed, and the PLC program and WinCC program are written for the corresponding fusion method. The practical application of the underground gas pumping pump station shows that the system has strong fusion ability, which can meet the integration of extraction parameters, environmental parameters, electric parameters, pipeline parameters, working conditions parameters, and other data required by the unattended system, improve the data utilization rate of the unattended system, and realize the complex control functions of the gas pumping system such as one-key start-stop and one-key rotation vacuum pump. The use of data-driven execution instead of manual operation effectively reduces the duty personnel of the underground gas pumping station, provides a guarantee for the less manned or unmanned operation of the gas pumping pump station, reduces the unplanned downtime of the pumping system, improves the efficiency of gas pumping, and ensures the safety of coal mine production.
Simulation study on the performance of heat pump air conditioning system for pure electric vehicles
Authors: Niu Junjia , Wang Yichun , Guo Fen 
Published: June 2024

Abstract
This study constructed an experimental bench for a R134a heat pump air conditioning system in a commercial electric vehicle. Based on the results from the experimental bench, the simulation model of the heat pump air conditioning system developed by AMESim was calibrated, and its reliability was verified. As the compressor and electronic expansion valve (EXV) are essential control components of the heat pump air conditioning system, simulations were conducted to investigate the impact of EXV opening on performance parameters such as refrigerating capacity, subcooling, superheat compressor power consumption, and Coefficient of Performance (COP) at different compressor speeds. The findings indicate that EXV opening significantly affects system subcooling and COP, and higher COP can be obtained by controlling the subcooling of the system through the EXV.
Research on reactive voltage control strategy for substations connected to photovoltaic systems
Authors: Ma Zhenliang , Liu Junwei , Jiang Jingxuan 
Published: June 2024

Abstract
The reactive voltage control of conventional substations is mainly realized by adjusting the switching of capacitors or reactors and changing the transformer ratio, which can only be controlled discretely. The PV inverter can carry out continuous reactive power control, and the reactive voltage control strategy of the conventional substation does not consider the reactive power control of the PV. In this paper, the nine-zone diagram control strategy of the traditional substation is used as a reference, and the reactive voltage optimization control strategy of a substation with a photovoltaic power generation system is constructed considering the characteristics that photovoltaic inverter can continuously regulate reactive power. Taking the internal power grid of an enterprise as an example, the simulation analysis verifies the effectiveness of the control strategy, which can ensure that the voltage and power factor of the grid-connected access point are qualified. At the same time, the voltage fluctuation of the grid-connected point can be reduced, and the network consumption can be reduced.
Simulink modeling analysis based on oil-electric hybrid six-rotor UAV
Authors: Tu Chuan , Liu Jianhong , Yan Zhiwei 
Published: June 2024

Abstract
Given the variable load caused by fuel consumption when the oil-electric hybrid six-rotor UAV is in actual flight, which leads to the slow response of flight attitude, Simulink modeling and analysis are carried out. Firstly, the Newton-Euler model is established for the UAV body by analyzing the motion dynamics of the UAV body. Then, the test method is used to model the oil-electric hybrid system, mainly considering the fuel consumption of the engine. The test results show that the transmission efficiency of the engine and the generator is 85 %, the maximum power of the engine can output 2.8 kW, the maximum power transmitted to the generator can output 2.38 kW, and the maximum power transmitted to the motor is 2.2 kW, which can realize the maximum peak power requirement of the UAV.
Mechanical and microstructural characterization of AISI SAE 4130 steel welded joints made by robotic gas metal arc welding process: influence of electrode work angle in 'T' welded joints
Authors: Wordofa Tesfaye Negash , Perumalla Janaki Ramulu , Sharma Abhay 
Published: June 2024

Abstract
Microstructural variations within welded metals, specifically in terms of phases and their corresponding volume fractions, play a crucial role in influencing weld strength and other mechanical properties. Welded joints in a ‘T’ configuration pose a unique challenge due to the dynamic heat distribution caused by changes in the electrode work angle (EWA) between perpendicularly aligned plates. This study focuses on characterizing the microstructure and micro-hardness of ‘T’ welded joints in a 6 mm thick plate of AISI SAE 4130, welded using the robotic gas metal arc welding process. The examination covers three distinct zones: the base material (BM), the fusion zone (FZ), and the heat-affected zone (HAZ). The extent of the HAZ is meticulously measured on both the vertical and horizontal plates within the weld zones. The x-ray diffraction (XRD) analysis results indicated that the average crystallite size of the base metal and fusion zone is 25.75 nm and 24.51 nm respectively. As per the scanning electron microscope (SEM) image observations, the higher wire feed rate yields to brittle fracture surface. The torch angles notably influence the dimensions of the HAZ on the vertical and horizontal plates of a ‘T’-Joint. Welding at higher EWA and contact-tip-work-distance, results in a larger HAZ on the vertical plate. Conversely, employing a flattened EWA and an increased contact-tip-work-distance leads to a greater extent of the HAZ on the horizontal plate. Furthermore, the micro-hardness of the fusion zone and heat-affected zone demonstrates an increase at higher settings of wire feed rate and travel speed. This phenomenon is attributed to the elevated heat inputs, which contribute to the formation of a finer microstructure within the weldment.