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Distribution characteristics and control optimization of anode and cathode water in fuel cells under low humidification

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APPLIED ENERGY 2025年 377卷

作者： Zeng, Ziteng Hu, Zunyan Liu, Huize Zhang, Yifu Ye, Kang Li, Jianqiu Xu, Liangfei Ouyang, Minggao Dong, Kan Tsinghua Univ State Key Lab Intelligent Green Vehicle & Mobil Beijing 100084 Peoples R China China Acad Railway Sci Co Ltd Locomot & Car Res Inst Beijing 100081 Peoples R China Beijing Zongheng Electromech Technol Co Ltd Beijing 100094 Peoples R China

Water management is a critical technology that significantly impacts the performance and lifespan of proton exchange membrane fuel cells (PEMFCs). While previous studies have predominantly focused on cathode water management, insufficient attention has been given to anode water management, particularly the phenomenon of anode flooding. In this paper, we analyze the water distribution characteristics between the anode and cathode under low humidification conditions and varying loads. We established a one-dimensional mass transport model for anode flooding analysis, achieving a model prediction error of less than 2 % in drainage ratio tests. Finally, we analyzed water distribution under various extreme conditions and proposed optimized parameters for the membrane electrode assembly to mitigate anodic flooding.

关键词： Fuel cell Hydrogen Water management Anode flooding structural parameter optimization

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Research on energy loss mechanism and optimization method of liquid ring vacuum pump based on entropy production theory

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VACUUM 2025年 232卷

作者： Liu, Huayi Zhao, Guoyong Yu, Shuo Li, Qingyun Li, Yanjie Meng, Fanrui Shandong Univ Technol Sch Mech Engn Zibo 255000 Peoples R China Zibo Water Ring Vacuum Pump Factory CO LTD Zibo 255200 Peoples R China

To solve the problem of high energy consumption of liquid ring vacuum pumps and serious hydraulic losses that make it difficult to improve the efficiency of the pumps. Firstly, the mechanism of the influence of radical clearance on the energy loss of liquid ring vacuum pumps is investigated, and a directional and quantitative analysis of the energy loss in the flow field within a liquid ring vacuum is made based on the entropy production theory. Then the structural parameter control model oriented to the maximum suction capacity and minimum wall effect entropy production of the liquid ring vacuum pump is established. The results indicate that turbulent entropy production and wall entropy production dominate the energy losses of liquid ring vacuum pumps with radial clearance of 24 mm, 28 mm, 32 mm, and 36 mm. The entropy production caused by the wall effect mainly occurs at the shell of the gas compression region. The optimized liquid ring vacuum pump model achieves an increase in suction capacity of 8.74 %, an increase in isothermal compression efficiency of 3.75 %, and a reduction in wall effect entropy production of 19.7 %.

关键词： Liquid ring vacuum pump Entropy production Hydraulic losses Radial clearance structural parameter optimization

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Casing failure mechanism and slip anchoring optimization of the compression packer in the oil and gas well

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING 2024年第6期238卷 2759-2769页

作者： Tang, Yang Wang, Jie Zhou, Minghai Li, Guangyao Xiao, Xiao Southwest Petr Univ Sch Mechatron Engn 8 Xindu Rd Chengdu 610500 Peoples R China Southwest Petr Univ Energy Equipment Inst Chengdu 610500 Peoples R China

The packer is a key tool to isolate downhole pressure during well testing and completion operations. The compression packer in the oil and gas wellbore needs to be anchored by hard contact between the slips and the casing when setting, which will cause the casing to suffer from occlusal damage and shorten the working life. It is necessary to combine casing damage and anchoring performance of the slip, select suitable packer slip material, and optimize its structural parameters to reduce casing hard contact damage and increase the working life of the slips and casing. Based on mechanical analysis and hard contact mechanism of the slip during the packer setting process, and selecting the slip material lower than the mechanical properties of the casing material, a finite element analysis model of interaction between the slips and the casing was established. The changes of slip equivalent plastic strain, maximum Mises stress, and CPRESS stress under three parameters of slip tooth number, tooth space, and tooth top angle were comprehensively evaluated. The results of analysis show that with the increase in the tooth number of slips, the tooth space or the top angle, the bending moment of slips increased, and the anchoring performance decreased. As the tooth number of slips, the tooth space or the top angle decreased, the damage of slip teeth increased. The combination optimization analysis of the above parameters was carried out using the orthogonal experiment method, and the optimal top angle of the slip structure of the compression packer is 90 degrees, the tooth space is 4 mm, and the tooth number is 20. Compared with the anchoring performance of soluble metal slips, the optimized slips significantly reduce the damage to the casing. The study will provide a theoretical basis and date support for further analysis of the anchoring performance of the slip, the reduction of casing damage, and the design of new slips.

关键词： Failure mechanism compression packer casing soluble slip finite element analysis structural parameter optimization

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A lightweight optimal design method for magnetic adhesion module of wall-climbing robot based on surrogate model and DBO algorithm

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JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY 2024年第4期38卷 2041-2053页

作者： Yang, Pei Sun, Lingyu Zhang, Minglu Chen, Haiyong Hebei Univ Technol Sch Mech Engn Tianjin 300130 Peoples R China Hebei Univ Technol Sch Artificial Intelligence Tianjin 300130 Peoples R China

This research combines simulation technology, a surrogate model, and a dung beetle optimizer (DBO) to propose a structural optimization design method for lightweight adhesive modules. The structure of the wall-climbing robot is introduced, and its adhesion stability is analyzed. Through simulation comparison of four typical Halbach array magnetic circuit modes, it was determined that the adhesion generated by the three-magnetic circuit structure mode is more advantageous. Determine the parameters that need to be optimized through sensitivity analysis. The Chebyshev model of adhesion force and parameters was established. An optimization model aimed at lightweight and the constraints of adhesion stability and structural parameters was set. The penalty function combined with DBO was used to solve the optimization model. Compared with before optimization, the weight of the adhesive module is reduced by 11.7 %. The experiments verified the adhesive module's adhesion force and the robot's load capacity.

关键词： Wall-climbing robot Magnetic adhesion module structural parameter optimization Surrogate model Dung beetle optimizer (DBO)

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Study on damaged micro-mechanism of pipe wall during braking and anchoring process of pipeline intelligent plugging robot

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING 2024年第3期238卷 1229-1239页

作者： Tang, Yang Minghai, Zhou Sun, Peng Wu, Jie Wang, Qiang Wu, Ju Southwest Petr Univ Sch Mechatron Engn Chengdu Peoples R China Southwest Petr Univ Oil & Gas Equipment Technol Sichuan Sci & Technol Chengdu Peoples R China PetroChina Southwest Oil & Gas Field Co Chengdu Peoples R China Sichuan Aerosp Fenghuo Serv Control Technol Corp Chengdu Peoples R China Southwest Petr Univ Sch Mechatron Engn Chengdu 610500 Sichuan Peoples R China

Pipeline intelligent plugging robot (PIPR) realizes braking and anchoring through hard contact of slip and pipeline. This process will cause bite marks on the inner wall of the pipeline, which will aggravate corrosion and shorten the service life of the pipeline. Therefore, it is necessary to comprehensively consider slip anchoring performance and degree of pipe -line damage, and optimize slip structure parameters of PIPR, to reduce the damage caused by hard contact between slip and pipeline. Based on force analysis and the hard contact mechanism of PIPR in the course of the anchoring process, the damage factors of pipe walls are analyzed, and a finite element analysis model of slip and pipeline is established. The plastic strain of the inner surface of the pipeline, the plastic strain of slip, and the von Mises stress under three parameters of slip tooth top angle, tooth inclination angle, and tooth number are comprehensively evaluated. In addition, visible indoor tests are established to verify the simulation model. The results show that the optimal tooth structure of slip is tooth top angle theta = 65 degrees, tooth inclination angle gamma = 60 degrees, and tooth number m = 18. This study will provide a reference for the optimal design of the slip of PIPR. It has important engineering significance for the successful implementation of its anchoring operations.

关键词： Pipeline intelligent plugging robot slip damage of pipe wall damage mechanism structural parameter optimization

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Optimizing surface quality in thermoplastic composites: A novel approach to mitigate dry spot defects in multi-prismatic array stamping

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JOURNAL OF MANUFACTURING PROCESSES 2024年 131卷 1846-1856页

作者： Li, Xinguo Liu, Chao Li, Yue Sun, Zeyu Zhou, Jianfeng Gao, Yu Zhu, Shu Donghua Univ Shanghai Collaborat Innovat Ctr HighPerformance Fi State Key Lab Modificat Chem Fibers & Polymer Mat Ctr Civil Aviat CompositesKey Lab High Performanc Shanghai 201620 Peoples R China Donghua Univ Coll Mat Sci & Engn Key Lab Shanghai City lightweight composites Shanghai 201620 Peoples R China Shanghai Donghua Composites Co Ltd Shanghai 201600 Peoples R China Suzhou Kongtian Composites Co Ltd Jiangsu 215228 Peoples R China Shanghai Jiao Tong Univ Frontiers Sci Ctr Transformat Mol Sch Chem & Chem Engn Shanghai 201306 Peoples R China

Stamp forming of complex structures in continuous fiber reinforced thermoplastic composites (CFRTPs) poses intricate molding challenges, particularly in surface quality maintenance. Dry spot defects, prevalent in such structures significantly compromise part rigidity, posing a pressing challenge in CFRTPs' practical application. This study focuses on multi-prismatic array structures, proposing a method to mitigate these defects in CFRTPs stamp forming. Forming simulations revealed the underlying causes of dry spot formation, leading to the optimization of two critical structural parameters: the chamfer radius (R) and the draft angle (theta). Simulation results indicated a substantial reduction in dry spot area, decreasing from 10 % to 0.28 % after optimization. Subsequent forming experiments confirmed the effectiveness of this approach, yielding multi-prismatic array samples with minimal dry spot. This strategy presents a novel and efficient means to address dry spot defects in complex CFRTPs parts stamp forming.

关键词： Continuous fiber reinforced thermoplastic composites (CFRTPs) Dry spot defect structural parameter optimization

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Parallel 3-RSR Wrist Rehabilitation Mechanism and Motion Performance Analysis

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JOURNAL OF BIOMIMETICS BIOMATERIALS AND BIOMEDICAL ENGINEERING 2024年 66卷 63-76页

作者： Cui, Bingyan Yin, Chenxu Kai, Ju Zhe, Ma Li, Wenjing North China Univ Sci & Technol Tangshan 063210 Hebei Peoples R China

In order to help patients with wrist injuries to carry out recovery training, a simple and portable parallel 3-RSR wrist rehabilitation mechanism was introduced in order to achieve the expected therapeutic effect. Firstly, the parallel 3-RSR wrist rehabilitation mechanism is described. Taking the parallel mechanism as the research object, the degree of freedom is calculated and the pose is solved by analytical method, which verifies the rationality of the mechanism motion. Then, based on the boundary search method, the reachable workspace of the parallel wrist rehabilitation mechanism is analyzed, and the relevant workspace map is drawn. Finally, considering the reasonable optimization of the structural size of the workspace, the results show that the optimized reachable attitude workspace is significantly larger than the initial workspace. This study provides a theoretical reference for the ontology design of rehabilitation institutions.

关键词： Parallel mechanism 3-RSR Wrist joint rehabilitation Position inverse solution Working space structural parameter optimization Experimental evaluation

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Structure design and mechanical performance test of a direct ventricular assist device pneumatic flexible actuator

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INTERNATIONAL JOURNAL OF ARTIFICIAL ORGANS 2022年第1期45卷 35-43页

作者： Yun, Zhong Xu, Kang Yang, Fan Tang, Xiaoyan Cent South Univ Sch Mech & Elect Engn Changsha 410083 Hunan Peoples R China

The purpose of this research is to overcome the shortcomings of the current direct ventricular assist device in structure design, material selection and design a pneumatic flexible actuator that can be used to drive a fully flexible cup-shaped direct ventricular assist device according to the human heart shape. In this study, the structural parameters of the flexible actuator are initially determined based on the existing research, then the flexible actuator model is constructed with SOLIDWORKS, then the model is imported into ABAQUS for finite element simulation, lastly, the actuator structure is optimized according to the simulation results. The flexible actuator is made by molding, and its mold is made by 3D printing. Finally, the final structural plan is determined by testing the mechanical properties of the flexible actuator. The pneumatic flexible actuator designed in this research can be combined into the required direct ventricular assist device in a reasonable way, which will provide ideas for the design of a fully flexible direct ventricular assist device.

关键词： Direct ventricular assist device pneumatic flexible actuator structural parameter optimization finite element analysis mechanical performance test

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Limiting the wind-induced deflection amplitude of an overhead conductor: establishment of multi-rigid-body model and optimization of structural parameters

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JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY 2022年第7期36卷 3205-3216页

作者： Hu, Xin Wang, Zhangqi Tian, Rui North China Elect Power Univ Hebei Key Lab Elect Machinery Hlth Maintenance & Baoding 071003 Peoples R China

To limit the wind-induced deflection amplitude of an overhead conductor, this study proposes a calculation model and an optimization model for overhead lines. According to the geometric deformation relationship and the principle of energy conservation, a multi-rigid-body model (MRBM) is proposed for the wind-induced deflection of the overhead lines. An aeroelastic model wind tunnel test was designed to verify the accuracy of the MRBM;the efficiency of the MRBM was verified through comparison with the finite element model (FEM). The optimization model is presented, and the structural parameters of the transmission lines in the actual project are optimized and analyzed. The results show that the accuracy of the MRBM can meet engineering requirements;the solution time is shorter than FEM, and the MRBM is easily called by the optimization algorithm. The structural parameter optimization effectively limits the deflection amplitude of the overhead conductor according to the engineering requirements.

关键词： Overhead conductor Wind-induced deflection Multi-rigid-body model Wind tunnel test structural parameter optimization

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Bandpass Filter Design Using Deep Neural Network and Differential Evolution Algorithm

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ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2022年第11期47卷 14343-14354页

作者： Senel, Bilge Senel, Fatih Ahmet Suleyman Demirel Univ Dept Elect & Elect Engn TR-32260 Isparta Turkey Suleyman Demirel Univ Dept Comp Engn TR-32260 Isparta Turkey

In this study, we have used a hybrid approach to design parallel-coupled microstrip bandpass filters. It can take a long time to design a parallel-coupled microstrip bandpass filter within the desired constraints. We developed a two-phase approach to achieve an efficient design process. We chose 3 GHz as the center frequency of the designed filter. The 3 GHz center frequency is a standard frequency used in radar, maritime, and radio navigation applications. To optimize the structural parameters, we first created the surrogate model of the filter with a deep neural network. For this, we created our dataset with the EM simulator using five different structural parameters. Our dataset consists of the simulation output of S-11 and S-21 values in the specified frequency range between 2.5 GHz and 3.5 GHz. After creating the surrogate model, we optimized the structural parameters using the differential evolution algorithm. We tested our method by designing filters with different structure parameters in the optimization phase. We optimized the structural parameters for different bandwidths. The simulation results show that our method is accurate and reliable.

关键词： Microstrip band pass filter Deep learning Surrogate modeling Differential evolution structural parameter optimization

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