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Analysis of Maximum Liquid Carrying Capacity Based on Conventional Tubing Plunger Gas Lift

Energy Engineering 2024年第6期121卷 1521-1533页

作者： Yanqun Yu wenhao xu Yahui Huangfu Jinhai Liu Bensheng Wang Kai Liu College of Mechanical and Electronic Engineering China University of Petroleum(East China)Qingdao266580China Energy Technology&Services Oil Production Services Company CNOOCTianjin300450China

China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable productionof these gas wells, plunger-lift technology plays an important role. In order to fully understand and accurately graspthe drainage and gas production mechanisms of plunger-lift, a mechanical model of plunger-liquid column uplift inthe plunger-lift process was established, focusing on conventional plunger-lift systems and representative wellboreconfigurations in the Linxing region. The operating casing pressure of the plunger-lift process and the calculationmethod for the maximum daily fluid production rate based on the work regime with the highest fluid recovery ratewere determined. For the first time, the critical flow rate method was proposed as a constraint for the maximumliquid-carrying capacity of the plunger-lift, and liquid-carrying capacity charts for conventional plunger-lift withdifferent casing sizes were developed. The results showed that for 23/8 casing plunger-lift, with a well depth ofshallower than 808 m, the maximum drainage rate was 33 m3/d;for 27/8 casing plunger-lift, with a well depth ofshallower than 742 m, the maximum drainage rate was 50.15 m3/d;for 31/2 casing plunger-lift, with a well depthof shallower than 560 m, the maximum drainage rate was 75.14 m3/d. This research provides a foundation for thescientific selection of plunger-lift technology and serves as a decision-making reference for developing reasonableplunger-lift work regimes.

关键词： Unconventional well conventional tubing string plunger gas lift critical flow rate liquid carry-over chart version

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All-optical object identification and threedimensional reconstruction based on optical computing metasurface

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Opto-Electronic Advances 2023年第12期6卷 5-14页

作者： Dingyu xu wenhao xu Qiang Yang Wenshuai Zhang Shuangchun Wen Hailu Luo Laboratory for Spin Photonics School of Physics and ElectronicsHunan UniversityChangsha 410082China School of Physics and Chemistry Hunan First Normal UniversityChangsha 410205China.

Object identification and three-dimensional reconstruction techniques are always attractive research interests in machine vision,virtual reality,augmented reality,and biomedical engineering.Optical computing metasurface,as a two-dimensional artificial design component,has displayed the supernormal character of controlling phase,amplitude,polarization,and frequency distributions of the light beam,capable of performing mathematical operations on the input light field.Here,we propose and demonstrate an all-optical object identification technique based on optical computing metasurface,and apply it to 3D reconstruction.Unlike traditional mechanisms,this scheme reduces memory consumption in the processing of the contour surface extraction.The identification and reconstruction of experimental results from high-contrast and low-contrast objects agree well with the real objects.The exploration of the all-optical object identification and 3D reconstruction techniques provides potential applications of high efficiencies,low consumption,and compact systems.

关键词： object identification three-dimensional reconstruction optical computing metasurface

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Neural network-based model predictive control with fuzzy-SQP optimization for direct thrust control of turbofan engine

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Chinese Journal of Aeronautics 2022年第12期35卷 59-71页

作者： Yangjing WANG Jinquan HUANG Wenxiang ZHOU Feng LU wenhao xu Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

A nonlinear model predictive control method based on fuzzy-Sequential Quadratic Programming(SQP)for direct thrust control is proposed in this paper for the sake of improving the accuracy of thrust control.The designed control system includes four parts,namely a predictive model,rolling optimization,online correction,and feedback correction.Considering the strong nonlinearity of engine,a predictive model is established by Back Propagation(BP)neural network for the entire flight envelope,whose input and output are determined with random forest algorithm and actual situation analysis.Rolling optimization typically uses SQP as the optimization algorithm,but SQP algorithm is easy to trap into local optimization.Therefore,the fuzzy-SQP algorithm is proposed to prevent this disadvantage using fuzzy algorithm to determine the initial value of SQP.In addition to the traditional three parts of model predictive control,an online correction module is added to improve the predictive accuracy of the predictive model in the predictive time domain.Simulation results show that the BP predictive model can reach a certain degree of predictive accuracy,and the proposed control system can achieve good tracking performance with the limited parameters within the safe range。

关键词： Direct thrust control Fuzzy-SQP algorithm Limit protection Neural network Nonlinear model predictive control Random forest Turbofan engine

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基于四电平编码与弱光通信的极低功耗传光式电流互感器

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电力系统保护与控制 2024年第5期52卷 148-157页

作者：徐文浩徐启峰谢楠福州大学电气工程与自动化学院福建福州350108

针对传光式电流互感器高压侧现有的母线取能和激光供能方式存在供电死区、能量转换效率低、使用寿命不足等问题,提出一种基于四电平编码与弱光通信的极低功耗光电传输系统方案。首先,设计三态门电路将信号采集模块的采样时钟和数据信号... 详细信息

针对传光式电流互感器高压侧现有的母线取能和激光供能方式存在供电死区、能量转换效率低、使用寿命不足等问题,提出一种基于四电平编码与弱光通信的极低功耗光电传输系统方案。首先,设计三态门电路将信号采集模块的采样时钟和数据信号叠加为一个四电平信号。然后,利用超高亮度且极低功耗的LED将四电平信号转换为光信号并通过光纤传输至低压侧。最后,在低压侧通过高灵敏度雪崩光电二极管探测器进行弱光检测后输入解码电路实现信号解码。将极低功耗光电传输系统应用于传光式电流互感器中进行实验验证,测量结果满足0.2级精度要求,系统高压侧的平均功耗可降低至3.91 mW,保证测量精度的同时大幅降低了功耗。由于高压侧的功耗极低,故可采用大容量电池或小功率光伏系统等可靠供能方案,从而解决了高压侧的供能问题,提高了系统的稳定性和可靠性。

关键词：传光式电流互感器极低功耗三态门四电平编码弱光通信信号解码

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Analysis of grinding mechanics and improved grinding force model based on randomized grain geometric characteristics

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Chinese Journal of Aeronautics 2023年第7期36卷 160-193页

作者： Mingzheng LIU Changhe LI Yanbin ZHANG Min YANG Teng GAO Xin CUI Xiaoming WANG wenhao xu Zongming ZHOU Bo LIU Zafar SAID Runze LI Shubham SHARMA School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Hanergy(Qingdao)Lubrication Technology Co. LTDQingdao 266520China Sichuan Future Aerospace Industry LLC Shifang 618400China Department of Sustainable and Renewable Energy Engineering University of SharjahSharjah 27272United Arab Emirates Department of Biomedical Engineering University of Southern CaliforniaLos AngelesCA 90089–1111USA Department of Mechanical Engineering I.K.Gujral Punjab Technical UniversityJalandhar 144603India

Too high grinding force will lead to a large increase in specific grinding energy, resulting in high temperature in grinding zone, especially for the aerospace difficult cutting metal materials,seriously affecting the surface quality and accuracy. At present, the theoretical models of grinding force are mostly based on the assumption of uniform or simplified morphological characteristics of grains, which is inconsistent with the actual grains. Especially for non-engineering grinding wheel,most geometric characteristics of grains are ignored, resulting in the calculation accuracy that cannot guide practical production. Based on this, an improved grinding force model based on random grain geometric characteristics is proposed in this paper. Firstly, the surface topography model of CBN grinding wheel is established, and the effective grain determination mechanism in grinding zone is revealed. Based on the known grinding force model and mechanical behavior of interaction between grains and workpiece in different stages, the concept of grain effective action area is proposed. The variation mechanism of effective action area under the influence of grain geometric and spatial characteristics is deeply analyzed, and the calculation method under random combination of five influencing parameters is obtained. The numerical simulation is carried out to reveal the dynamic variation process of grinding force in grinding zone. In order to verify the theoretical model, the experiments of dry grinding Ti-6Al-4 V are designed. The experimental results show that under different machining parameters, the results of numerical calculation and experimental measurement are in good agreement, and the minimum error value is only 2.1 %, which indicates that the calculation accuracy of grinding force model meets the requirements and is feasible. This study will provide a theoretical basis for optimizing the wheel structure, effectively controlling the grinding force range, adjusting the grinding zone temperature and improving the workpiece

关键词： Effective action area Grinding force Improved model Mechanical behaviour Randomized grain

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Limit protection design in turbofan engine acceleration control based on scheduling command governor

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Chinese Journal of Aeronautics 2021年第10期34卷 67-80页

作者： wenhao xu Jinquan HUANG Jiakun QIN Muxuan PAN College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A new limit protection method based on Scheduling Command Governor(SCG) is proposed for imposing multiple constraints on a turbofan engine during acceleration process. A Gain Scheduling Controller(GSC) is designed for the transient state control and its stability proof is developed using Linear Matrix Inequalities(LMIs). The SCG is an add-on control scheme which manages engine limits effectively based on reference trajectory optimization. Unlike the traditional min–max architecture with switching logic, the SCG method utilizes the Linear Parameter Varying(LPV) closed-loop model to form a prediction of future constraint violation and per instant solves a constraint-admissible reference within an approximate Maximal Output Admissible Set(MOAS).The influence of the variation of engine dynamic characteristics and equilibrium points during transient state control is handled by the design of contractive sets. Simulation results on a turbofan engine component-level model show the applicability and effectiveness of the SCG method. Compared to the traditional min–max method, the SCG method has less conservativeness. In addition,the design of contractive sets makes conservativeness tunable.

关键词： Command governors Constrained control Contractive sets Gain scheduling Limit protection LPV model Turbofan engines

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Elucidating the clinical and immunological value of m6A regulatormediated methylation modification patterns in adrenocortical carcinoma

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Oncology Research 2023年第5期31卷 819-831页

作者： wenhao xu HAOMING LI YASIR HAMEED MOSTAFA A.ABDEL-MAKSOUD SAEEDAH MUSAED ALMUTAIRI AYMAN MUBARAK MOHAMMED AUFY WAEL ALTURAIKI ABDULAZIZ J.ALSHALANI AYMAN M.MAHMOUD CHEN LI Department of Urology Urological Surgery Research InstituteFirst Affiliated HospitalArmy Medical University(Third Military Medical University)ChongqingChina Department of Urology Affiliated Hospital of Guilin Medical UniversityGuilinChina Department of Applied Biological Sciences Tokyo University of ScienceTokyoJapan Department of Botany and Microbiology College of ScienceKing Saud UniversityRiyadhSaudi Arabia Department of Pharmaceutical Sciences Division of Pharmacology and ToxicologyUniversity of ViennaViennaAustria Department of Medical Laboratory Sciences College of Applied Medical SciencesKing Saud UniversityRiyadhSaudi Arabia Department of Life Sciences Faculty of Science and EngineeringManchester Metropolitan UniversityManchesterUK Department of Biology ChemistryPharmacyFree University of BerlinBerlinGermany

N6-methyladenosine methylation(m6A)is a common type of epigenetic alteration that prominently affects the prognosis of tumor patients.However,it is unknown how the m6A regulator affects the tumor microenvironment(TME)cell infiltration in adrenocortical carcinoma(ACC)and how it affects the prognosis of ACC patients yet.The m6A alteration patterns of 112 ACC patients were evaluated,furthermore,the association with immune infiltration cell features was investigated.The unsupervised clustering method was applied to typify the m6A alteration patterns of ACC patients.The principal component analysis(PCA)technique was taken to create the m6A score to assess the alteration pattern in specific malignancies.We found two independent patterns of m6A alteration in ACC patients.The TME cell infiltration features were significantly in accordance with phenotypes of tumor immune-inflamed and immune desert in both patterns.The m6Ascore also served as an independent predictive factor in ACC patients.The somatic copy number variation(CNV)and patients prognosis can be predicted by m6A alteration patterns.Moreover,the ACC patients with high m6A scores had better overall survival(OS)and higher efficiency in immune checkpoint blockade therapy.Our work demonstrated the significance of m6A alteration to the ACC patients immunotherapy.The individual m6A alteration patterns analysis might contribute to ACC patients prognosis prediction and immunotherapy choice.

关键词： m6A Tumor microenvironment Adrenocortical carcinoma Immunotherapy Prognosis

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Electrostatic atomization minimum quantity lubrication machining:from mechanism to application

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International Journal of Extreme Manufacturing 2022年第4期4卷 58-100页

作者： wenhao xu Changhe Li Yanbin Zhang Hafiz Muhammad Ali Shubham Sharma Runze Li Min Yang Teng Gao Mingzheng Liu Xiaoming Wang Zafar Said Xin Liu Zongming Zhou School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520People's Republic of China State Key Laboratory of Ultra-Precision Machining Technology Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHong KongPeople's Republic of China Mechanical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Department of Mechanical Engineering IK Gujral Punjab Technical UniversityPunjab 144603India Department of Biomedical Engineering University of Southern CaliforniaLos AngelesCA 90089-1111United States of America College of Engineering University of SharjahSharjah 27272United Arab Emirates School of Mechanical Engineering Dalian University of TechnologyDalian 116024People's Republic of China Hanergy(Qingdao)Lubrication Technology Co.LTD Qingdao 266520People's Republic of China

Metal cutting fluids(MCFs)under flood conditions do not meet the urgent needs of reducing carbon emission.Biolubricant-based minimum quantity lubrication(MQL)is an effective alternative to flood lubrication.However,pneumatic atomization MQL has poor atomization properties,which is detrimental to occupational health.Therefore,electrostatic atomization MQL requires preliminary exploratory studies.However,systematic reviews are lacking in terms of capturing the current research status and development direction of this technology.This study aims to provide a comprehensive review and critical assessment of the existing understanding of electrostatic atomization MQL.This research can be used by scientists to gain insights into the action mechanism,theoretical basis,machining performance,and development direction of this technology.First,the critical equipment,eco-friendly atomization media(biolubricants),and empowering mechanisms of electrostatic atomization MQL are presented.Second,the advanced lubrication and heat transfer mechanisms of biolubricants are revealed by quantitatively comparing MQL with MCF-based wet machining.Third,the distinctive wetting and infiltration mechanisms of electrostatic atomization MQL,combined with its unique empowering mechanism and atomization method,are compared with those of pneumatic atomization MQL.Previous experiments have shown that electrostatic atomization MQL can reduce tool wear by 42.4%in metal cutting and improve the machined surface Ra by 47%compared with pneumatic atomization MQL.Finally,future development directions,including the improvement of the coordination parameters and equipment integration aspects,are proposed.

关键词： cutting grinding minimum quantity lubrication electrostatic atomization biolubricant

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黏声波方程波场模拟的通用格式自适应系数频域有限差分方法

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地球物理学报 2024年第2期67卷 654-669页

作者：徐文豪巴晶 J.M.Carcione 朱鹤松河海大学地球科学与工程学院南京211100 National Institute of Oceanography and Applied Geophysics-OGS Borgo Grotta Gigante 42/cTriesteSgonico 34010Italy

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency domain,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格... 详细信息

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency domain,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格点数小于4时误差较大.通过令FDFD系数随一个波长内的网格点数自适应从而提高FDFD方法的精度,本文针对黏声波波场模拟发展了一种适用于不同空间采样间隔之比的通用格式自适应系数FDFD方法.同时,为了验证自适应系数FDFD方法对一般黏声波模型的有效性,本文针对三个典型的黏声波模型,分别采用解析解和基于高阶FDFD的参考解验证了所提出方法的有效性.本方法的FDFD格式通过在传统的二阶FDFD格式的基础上引入相关校正项得到,其中校正项按网格点与中心点的距离进行分类选取,同时校正项对应的自适应FDFD系数不仅和空间采样间隔之比相关,还和一个波长内的采样点数相关.所需的自适应FDFD系数可通过声波方程的数值频散关系和查找表高效给出.数值频散分析表明,在空间采样间隔相等或不等的情况下,以相速度误差不超过1%为标准,通用格式自适应系数FDFD方法所需的一个波长内的采样点数均小于2.5.数值模拟实验表明,对于不同的空间采样间隔之比,相对于常用的二阶五点FDFD方法和优化九点FDFD方法,通用格式自适应系数FDFD方法均可在相似的计算量和内存需求下,有效提高黏声波模拟的精度.

关键词：黏声波频域有限差分自适应系数波场模拟通用格式

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Nanoparticle-enhanced coolants in machining:mechanism,application,and prospects

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Frontiers of Mechanical Engineering 2023年第4期18卷 1-47页

作者： Shuguo HU Changhe LI Zongming ZHOU Bo LIU Yanbin ZHANG Min YANG Benkai LI Teng GAO Mingzheng LIU Xin CUI Xiaoming WANG wenhao xu Y.S.DAMBATTA Runze LI Shubham SHARMA School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Hanneng(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266100China Sichuan New Aviation TA Technology Co. Ltd.Shifang 618400China Mechanical Engineering Department Ahmadu Bello UniversityZaria 810106Nigeria Massachusetts Institute of Technology CambridgeMA 02139USA Department of Mechanical Engineering IK Gujral Punjab Technical UniversityPunjab 144603India

Nanoparticle-enhanced coolants(NPECs)are increasingly used in minimum quantity lubrication(MQL)machining as a green lubricant to replace conventional cutting fluids to meet the urgent need for carbon emissions and achieve sustainable manufacturing.However,the thermophysical properties of NPEC during processing remain unclear,making it difficult to provide precise guidance and selection principles for industrial applications.Therefore,this paper reviews the action mechanism,processing properties,and future development directions of NPEC.First,the laws of influence of nano-enhanced phases and base fluids on the processing performance are revealed,and the dispersion stabilization mechanism of NPEC in the preparation process is elaborated.Then,the unique molecular structure and physical properties of NPECs are combined to elucidate their unique mechanisms of heat transfer,penetration,and antifriction effects.Furthermore,the effect of NPECs is investigated on the basis of their excellent lubricating and cooling properties by comprehensively and quantitatively evaluating the material removal characteristics during machining in turning,milling,and grinding applications.Results showed that turning of Ti‒6Al‒4V with multi-walled carbon nanotube NPECs with a volume fraction of 0.2%resulted in a 34%reduction in tool wear,an average decrease in cutting force of 28%,and a 7%decrease in surface roughness Ra,compared with the conventional flood process.Finally,research gaps and future directions for further applications of NPECs in the industry are presented.

关键词： nanoparticle-enhanced coolant minimum quantity lubrication biolubricant thermophysical properties turning milling grinding

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