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Energy Engineering 2024年第6期121卷 1607-1636页

作者： yuanjun dai Haonan Li Baohua Li College of Machine Shanghai DianJi UniversityShanghai201306China

This paper addresses the micro wind-hydrogen coupled system,aiming to improve the power tracking capability of micro wind farms,the regulation capability of hydrogen storage systems,and to mitigate the volatility of wind power generation.A predictive control strategy for the micro wind-hydrogen coupled system is proposed based on the ultra-short-term wind power prediction,the hydrogen storage state division interval,and the daily scheduled output of wind power generation.The control strategy maximizes the power tracking capability,the regulation capability of the hydrogen storage system,and the fluctuation of the joint output of the wind-hydrogen coupled system as the objective functions,and adaptively optimizes the control coefficients of the hydrogen storage interval and the output parameters of the system by the combined sigmoid function and particle swarm algorithm(sigmoid-PSO).Compared with the real-time control strategy,the proposed predictive control strategy can significantly improve the output tracking capability of the wind-hydrogen coupling system,minimize the gap between the actual output and the predicted output,significantly enhance the regulation capability of the hydrogen storage system,and mitigate the power output fluctuation of the wind-hydrogen integrated system,which has a broad practical application prospect.

关键词： Micro wind-hydrogen coupling system ultra-short-term wind power prediction sigmoid-PSO algorithm adaptive roll optimization predictive control strategy

Influence of Trailing-Edge Wear on the Vibrational Behavior of Wind Turbine Blades

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Fluid Dynamics & Materials Processing 2024年第2期20卷 337-348页

作者： yuanjun dai Xin Wei Baohua Li Cong Wang Kunju Shi Mechanical College Shanghai Dian Ji UniversityShanghai201306China College of Energy Engineering Xinjiang Institute of EngineeringUrumqi830091China

To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal tests.According to these experiments,the natural frequencies of trailing-edge worn blades-1,-2,and-3 increase the most in the second to fourth order,theﬁfth order increases in the middle,and theﬁrst order increases the least.The damping ratio data indi-cate that,in general,theﬁrstﬁve-order damping ratios of trailing-edge worn blades-1 and trailing-edge worn blades-2 are reduced,and theﬁrstﬁve-order damping ratios of trailing-edge worn blades-3 are slightly improved.The mode shape diagram shows that the trailing-edge worn blades-1 and-2 have a large swing in the tip and the blade,whereas the second-and third-order vibration shapes of the trailing edge-worn blade-3 tend to be improved.Overall,all these results reveal that the blade’s mass and the wear area are the main fac-tors affecting the vibration characteristics of wind turbine blades.

关键词： Wind turbine modal test natural frequency damping ratio mode shape

Influence of Flap Parameters on the Aerodynamic Performance of a Wind-Turbine Airfoil

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Fluid Dynamics & Materials Processing 2024年第4期20卷 771-786页

作者： yuanjun dai Jingan Cui Baohua Li Cong Wang Kunju Shi Mechanical College Shanghai DianJi UniversityShanghai201306China College of Energy Engineering Xinjiang Institute of TechnologyUrumqi830091China

A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coefficient,and drag coefficient.The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil;however,at small attack angles,its influence is significantly reduced.When the angle of attack exceeds the critical stall angle and the flap height is 1.5%of the chord length,the influence of the flap becomes very evident.As the flap height increases,the starting point of the separation vortex gradually moves forward and generates a larger wake vortex.Optimal aerodynamic characteristics are obtained for 1.5%(of the chord length)flap height and a 45°flap angle;in this case,the separation vortex is effectively reduced.

关键词： Airfoil flap height flap angle lift-drag ratio aerodynamic characteristics

Fourier neural operator with boundary conditions for efficient prediction of steady airfoil flows

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 2019-2038页

作者： yuanjun dai Yiran AN Zhi LI Jihua ZHANG Chao YU Department of Machanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Beijing Institute of Mechanical and Electrical Engineering Beijing 100074China

An efficient data-driven approach for predicting steady airfoil flows is proposed based on the Fourier neural operator(FNO),which is a new framework of neural networks.Theoretical reasons and experimental results are provided to support the necessity and effectiveness of the improvements made to the FNO,which involve using an additional branch neural operator to approximate the contribution of boundary conditions to steady solutions.The proposed approach runs several orders of magnitude faster than the traditional numerical methods.The predictions for flows around airfoils and ellipses demonstrate the superior accuracy and impressive speed of this novel approach.Furthermore,the property of zero-shot super-resolution enables the proposed approach to overcome the limitations of predicting airfoil flows with Cartesian grids,thereby improving the accuracy in the near-wall region.There is no doubt that the unprecedented speed and accuracy in forecasting steady airfoil flows have massive benefits for airfoil design and optimization.

关键词： deep learning(DL) Fourier neural operator(FNO) steady airfoil flow

Influence of the Blade Bifurcated Tip on the Correlation between Wind Turbine Wheel Vibration and Aerodynamic Noise

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Fluid Dynamics & Materials Processing 2023年第12期19卷 3033-3043页

作者： Baohua Li yuanjun dai Jingan Cui Cong Wang Kunju Shi Mechanical College Shanghai Dianji UniversityShanghai201306China College of Energy Engineering Xinjiang Institute of EngineeringUrumqi830091China

To reduce the vibration and aerodynamic noise of wind turbines,a new design is proposed relying on a blade with a bifurcated apex or tip.The performances of this wind turbine wheel are tested at the entrance of a DC(direct-action)wind tunnel for different blade tip angles and varying centrifugal force and aerodynamic loads.The test results indicate that the bifurcated apex can reduce the vibration acceleration amplitude and the vibration fre-quency of the wind wheel.At the same time,the bifurcated apex can lower the maximum sound pressure level corresponding to the rotating fundamental frequency of the wind wheel.According to all thesefindings,the tip angle of the bifurcated apex is the main factor enhancing the effect of the modification.

关键词： Wind turbine bifurcated apex wind wheel vibration aerodynamic noise

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静音水下航行器的水动力特性数值研究

北京大学学报（自然科学版） 2024年第2期60卷 203-209页

作者：戴袁鋆任世成张纪华余超北京大学工学院力学与工程科学系北京100871 北京机电工程研究所北京100074

为了克服传统螺旋桨推进航行器推进效率低、灵活性差和噪声大的缺点,针对一种仿生柔性体推进的水下航行器的水动力特性进行数值研究,分析柔性体波动的振幅和波数对水动力特性的影响、仿生表面对水动力性能的影响以及整体设计对水动力特... 详细信息

为了克服传统螺旋桨推进航行器推进效率低、灵活性差和噪声大的缺点,针对一种仿生柔性体推进的水下航行器的水动力特性进行数值研究,分析柔性体波动的振幅和波数对水动力特性的影响、仿生表面对水动力性能的影响以及整体设计对水动力特性的影响。数值结果表明,增大振幅将显著地增大静水推力,同时增加推进阻力;增加波数则显著地增加推进阻力,并减小静水推力。此外,使用仿生表面和现有的前尖端设计,可以减小推进阻力。研究结果有利于进一步优化航行器,提高航行器推进效率。

关键词：水下航行器仿生推进柔性体水动力特性

Full sexual maturity-cycle exposure to environmentally relevant concentrations of 17β-estradiol decreases reproductive capacity of zebrafish

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Journal of Environmental Sciences 2024年第3期137卷 580-592页

作者： Yongkang Zhang yuanjun Jiang Qian Sun Meng Li Sheng Chen Jingyu Liang Chunsheng Liu College of Fisheries Huazhong Agricultural UniversityWuhan 430070China School of Environmental Studies China University of GeosciencesWuhan 430074China

17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in fish.However,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of E2 for the full sexual maturation cycle remain unclear.In this study,zebrafish were treatment with 0,10 or100 ng/L E2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were assessed.The results showed that treatment with E2 lead to increased number of feminization in zebrafish.In females,E2 decreased cumulative amount of spawning and inhibited the maturation of oocyte.In males,E2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of sperm.These adverse effects on sperm might be responsible for the reduced fertilization observed in offspring.In addition,treatment with E2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in zebrafish.Overall,these results suggested that treatment with environmentally relevant concentrations of E2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.

关键词： Environmental estrogen Zebrafish Fecundity Gonadal development Endocrine disruption

Unstable evolution of railway slope under the rainfall-vibration joint action

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Journal of Mountain Science 2024年第4期21卷 1419-1431页

作者： DONG Haoyu WANG Jiading ZHANG Dengfei LI Lin XU yuanjun State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China

Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few scholars have explored the unstable evolution of railway slopes under the joint action of rainfall-vibration.Based on the model test of sandy soil slope,the unstable evolution process of slope under locomotive vibration,rainfall,and rainfall-vibration joint action conditions was simulated in this paper.By comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions,the change laws of pore pressure under the influence of vibration and rainfall were explored.The main control factors affecting the stability of slope structure under the joint action conditions were further defined.Combined with the slope failure phenomena under these three conditions,the causes of slope instability resulting from each leading factor were clarified.Finally,according to the above conclusions,the unstable evolution of the slope under the rainfall-vibration joint action was determined.The test results show that the unstable evolution process of sandy soil slope,under the rainfall-vibration joint action,can be divided into:rainfall erosion cracking,vibration promotion penetrating,and slope instability sliding three stages.In the process of slope unstable evolution,rainfall and vibration play the roles of inducing and promoting slide respectively.In addition,the deep cracks,which are the premise for the formation of the sliding surface,and the violent irregular fluctuation of soil pressure,which reflects the near penetration of the sliding surface,constitute the instability characteristics of the railway slope together.This paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration,hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes.

关键词： Rainfall vibration joint action Small scale model tests Unstable evolution process Unstable characteristics Inducing sliding and promoting sliding

飞机进气道中激波边界层干扰引起噪音的数值模拟

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Acta Mechanica Sinica 2022年第6期38卷 106-116,I0002页

作者：戴袁鋆安亦然李植张群峰 Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China

我们采用非线性声学求解器(NLAS)和Ffowcs-Williams/Hawkings(FW-H)方程对飞机进气道中由激波边界层干扰产生的噪音进行了数值研究.一个关于激波边界层干扰的标模问题用于验证流场特征,数值结果与实验结果有很好的一致性.在模拟激波边... 详细信息

我们采用非线性声学求解器(NLAS)和Ffowcs-Williams/Hawkings(FW-H)方程对飞机进气道中由激波边界层干扰产生的噪音进行了数值研究.一个关于激波边界层干扰的标模问题用于验证流场特征,数值结果与实验结果有很好的一致性.在模拟激波边界层干扰产生噪音的过程中,我们成功的观察到了喘振现象.正激波的震荡是一种小喘振,而内激波的震荡是一种大喘振,频率大约为100 Hz.远场噪音频谱表明远场噪音的主导频率与内激波震荡的频率很接近,这说明,内激波震荡决定了远场噪音的总声压级的量级.

关键词： Noise SBLI NLAS FW-H equation

Research on the Framework of the Construction of Financial Management Informatization

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Journal of Contemporary Educational Research 2018年第1期2卷 10-14页

作者： dai yuanjun Guangzhou Civil Aviation College

The development of our country’s financial industry can not do without new information technology.In this information age,all industries require the application of information technology.The arrival of the information age not only affects human life,but also promotes the effective development of economy and brings a lot of help to the development of financial economy.The imperfect construction of financial information management leads to a series of problems,which limits the progress of the construction of financial informatization.This article briefly introduces the current situation and existing problems of the construction of financial management informatization,puts forward reasonable and effective solving strategies to promote our country’s construction of financial management informatization.

关键词： financial institutions deficiencies construction standard solving strategies