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Void fraction measurement of bubble and slug flow in a small channel using the multivision technique

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Particuology 2017年第4期15卷 11-16页

作者： Huajun Li Xiaohu Zheng Haifeng Ji zhiyao huang Baoliang Wang Haiqing Li State Key Laboratory of Industrial Control Technology College of Control Science and Engineering Zhejiang University Hangzhou 310027 China

Using the multivision technique, a new void fraction measurement method was developed for bubble and slug flow in a small channel. The multivision system was developed to obtain images of the two-phase flow in two perpendicular directions. The obtained images were processed--using image segmentation, image subtraction, Canny edge detection, binarization, and hole filling-to extract the phase boundaries and information about the bubble or slug parameters, With the extracted information, a new void fraction measurement model was developed and used to determine the void fraction of the two-phase flow. The proposed method was validated experimentally in horizontal and vertical channels with different inner diameters of 2.1, 2.9, and 4.0 mm, The proposed method of measuring the void fraction has better performance than the methods that use images acquired in only one direction, with a maximum absolute difference between the measured and reference values of less than 6%.

关键词： Gas-liquid two-phase flow Void fraction Bubble flow Slug flow Multivision technique

Measurement of bubble velocity using Capacitively Coupled Contactless Conductivity Detection(C^4D)technique

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Particuology 2013年第2期11卷 198-203页

作者： Baoliang Wang Ying Zhou Haifeng Ji zhiyao huang Haiqing Li State Key Laboratory of Industrial Control Technology Department of Control Science and EngineeringZhejing University

The feasibility of applying Capacitively Coupled Contactless Conductivity Detection （C4D） technique to measurement of bubble velocity in gas-liquid two-phase flow in millimeter-scale pipe is investigated. And, a new method, which combines the C4D technique and the principle of cross-correlation velocity measurement, is proposed for the measurement of bubble velocity. This research includes two parts. First, based on the principle of C4 D, a new five-electrode C4D sensor is developed. Then, with two conductivity signals obtained by the C4D sensor, the velocity measurement of bubble is implemented according to the principle of cross-correlation. The research results indicate that the C4D technique is highly effective and anticipates a broad potential in the field of two-phase flow. Experimental results show that the five-electrode C4D sensor is suitable for measuring the velocity of single bubbles with a relative error of less than 5%.

关键词： Bubble Velocity measurement Capacitively Coupled Contactless Conductivity Detection Cross-correlation velocity measurement

Ultrasoft,sensitive fiber-like sensor by assembly of bacterial cellulose(BC)nanofibrils and BC molecules for biocompatible strain sensing

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Nano Research 2023年第3期16卷 4067-4076页

作者： Si Meng Yuyan Zhang Nihuan Wu Cheng Peng zhiyao huang Zhengjie Lin Cheng Qi Zhou Liu Tiantian Kong College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518000China Department of Biomedical Engineering School of MedicineShenzhen UniversityShenzhen 518000China D Printing Clinical Translational and Regenerative Medicine Center Shenzhen Qianhai Shekou Free Trade Zone HospitalShenzhen 518067China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518000China Department of Urology Inst Translat MedThe First Affiliated Hospital of Shenzhen UniversityShenzhen Second People’s HospitalShenzhen 518000China

The development of implantable bioelectronics is driven by emerging applications including continuous health monitoring and human-machine *** mechanical mismatch between implanted bioelectronics and tissues not only compromises device accuracy,but also causes interference with tissues *** address this issue,it is necessary to develop ultrasoft and biocompatible fiber strain sensor with proper stretchability and ***,we fabricate a bacterial cellulose-based sensing fiber which possesses the stretchability and elastic modulus(~102 kPa)close to those of soft *** addition,such fiber has high sensitivity to tiny tensile force/strain(8.8×10^(−3)N/2.5%)and low cell *** excellent properties make the bacterial cellulose(BC)-based sensing fiber an excellent candidate of implantable bioelectric devices for monitoring subtle motions of *** demonstrate this by applying it for continuous monitoring of human pulse and bullfrog ***(BC/oxBC)@PANI(ox=oxidized and PANI=polyaniline)fibers can further be woven into an array sensor and serve more complex sensing functions,such as multipoint force perception and shape recognition as demonstrated.

关键词： bioelectronics fiber bacteria cellulose spinning sensor

The Proof Dilemma of Porter’s Hypothesis:Analysis of Its Verification Difficulties

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Proceedings of Business and Economic Studies 2024年第3期7卷 109-113页

作者： zhiyao huang Jiajie Qu University of Glasgow Glasgow G128QQBritain Guangxi University of Finance and Economics Nanning 530001Guangxi Autonomous RegionChina

The Porter Hypothesis,proposed by Michael ***,suggests that stringent environmental regulations can enhance corporate innovation and competitiveness,challenging the traditional view that regulations increase business *** argues that regulations motivate firms to innovate,leading to improved productivity,cost reductions,and new market ***,there are proponents and critics in academia regarding the *** claim regulations change corporate behavior,reducing agency costs and boosting research and *** argue that if win-win situations exist,businesses would naturally pursue them without regulatory *** challenges in proving or refuting the hypothesis include its various versions,the difficulty in quantifying innovation and competitiveness,the complex interplay between regulation,innovation,and competitiveness,and the varying impacts across industries and ***,the effects may require a long time to manifest,and the hypothesis’s applicability is influenced by evolving environmental policies and market *** mixed empirical findings,the Porter Hypothesis provides a valuable framework for understanding the relationships among environmental regulation,innovation,and competitiveness,but its validation requires a more comprehensive assessment.

关键词： Porter Hypothesis Environmental regulations Innovate Competitive power

气液两相流差压波动信号的Hilbert-huang变换特性

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化工学报 2005年第12期56卷 2294-2302页

作者：丁浩黄志尧李海青浙江大学控制科学与工程学系工业控制技术国家重点实验室浙江杭州310027

将Hilberthuang(HHT)变换应用于中小管径水平管气液两相流差压波动信号的分析.利用经验模态分解(EMD)方法把信号分解成多个内模函数(IMF),再对各内模函数进行Hilbert变换,得到信号的Hilbert谱,并提取各内模函数的信号能量特征.在此基础... 详细信息

将Hilberthuang(HHT)变换应用于中小管径水平管气液两相流差压波动信号的分析.利用经验模态分解(EMD)方法把信号分解成多个内模函数(IMF),再对各内模函数进行Hilbert变换,得到信号的Hilbert谱,并提取各内模函数的信号能量特征.在此基础上比较了不同管径下信号分析的结果,分析了不同频段的能量分布与流型变迁的关系,并讨论了小波变换和HHT两种信号处理方法各自的特点.实验结果表明,HHT可以用于非线性非平稳信号的分析,提取的能量特征值反映了水平管气液两相流的流动状态和流型的变迁,该方法为水平管气液两相流差压波动信号的研究提供了借鉴.

关键词：气液两相流差压波动 Hilbert-huang变换经验模态分解内模函数

基于ECT传感器和模式识别的气液两相流空隙率测量新方法研究

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仪器仪表学报 2005年第6期26卷 557-561页

作者：王雷冀海峰黄志尧李海青工业控制技术国家重点实验室浙江大学控制系自动化仪表所

基于电容层析成像(ECT)传感器和模式识别理论,提出了一种新型的气液两相流空隙率测量方法。根据流型几何特征分别建立了空隙率的三个模板库。测量时先对流型进行分类,再调用对应的模板库利用距离测度进行模板匹配,从而得到空隙率。实验... 详细信息

基于电容层析成像(ECT)传感器和模式识别理论,提出了一种新型的气液两相流空隙率测量方法。根据流型几何特征分别建立了空隙率的三个模板库。测量时先对流型进行分类,再调用对应的模板库利用距离测度进行模板匹配,从而得到空隙率。实验结果表明该方法是可行的,有助于克服测量结果易受流型影响的问题,同时速度优于传统ECT技术方法,获得一个管截面空隙率值所花费的测量时间小于50ms,最大测量误差可小于5%,满足工业在线运行需要。

关键词：电容模式识别空隙率两相流测量

基于PCR和PLSR的油气两相流空隙率测量

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仪器仪表学报 2008年第4期29卷 705-710页

作者：李霞王保良黄志尧李海青工业控制技术国家重点实验室浙江大学控制科学与工程学系杭州310027

本文利用12电极ECT系统提供的电容测量信息,基于主成分回归(PCR)和偏最小二乘回归(PLSR)技术,提出了一种油气两相流空隙率测量的新方法。该方法针对不同的油气两相流流型,分别基于PCR和PLSR建立两组空隙率测量模型。实际测量时,根据流... 详细信息

本文利用12电极ECT系统提供的电容测量信息,基于主成分回归(PCR)和偏最小二乘回归(PLSR)技术,提出了一种油气两相流空隙率测量的新方法。该方法针对不同的油气两相流流型,分别基于PCR和PLSR建立两组空隙率测量模型。实际测量时,根据流型辨识结果分别选用相应的基于PCR的空隙率测量模型和基于PLSR的空隙率测量模型,通过计算获得空隙率值并进行对比。研究结果表明,本文提出的空隙率测量方法是有效的,两组空隙率测量模型的测量结果精度相当,在典型流型下的测量误差均在5%以内,但基于PLSR技术所获空隙率测量模型的降维效果优于基于PCR技术的相应模型。同时,由于该方法直接利用ECT系统提供的电容测量值来建立空隙率测量模型,省去了以往ECT系统测量空隙率所必需的复杂费时的图像重建过程,提高了空隙率测量的实时性,整个测量时间小于0.1s。

关键词：两相流空隙率电容主成分回归偏最小二乘回归

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基于Lamb波气体传感器的数据采集仪

北京航空航天大学学报 2017年第11期43卷 2216-2223页

作者：黄鸯鸯王保良冀海峰黄志尧李海青浙江大学控制科学与工程学院工业控制技术国家重点实验室杭州310027

Lamb波气体传感器因其具有高灵敏度、低损耗、多模式特性,在气体传感领域中展示出十分广阔的工业应用前景。然而,迄今为止,Lamb波气体传感器尚处于实验室基础研究阶段,其测试是基于网络分析仪,需人工读取测试结果并计算,不能实现自动获... 详细信息

Lamb波气体传感器因其具有高灵敏度、低损耗、多模式特性,在气体传感领域中展示出十分广阔的工业应用前景。然而,迄今为止,Lamb波气体传感器尚处于实验室基础研究阶段,其测试是基于网络分析仪,需人工读取测试结果并计算,不能实现自动获取被测参数,这在很大程度上限制了传感器的实际应用。针对现有测试技术的不足,研制了一种针对Lamb波气体传感器的数据采集仪。利用直接数字频率合成技术和嵌入式技术获取传感器的幅频特性和相频特性,通过多峰值快速搜索算法提取各个模式的最大峰值信息,并对传感器进行了各个模式下的扫频测试实验和算法验证实验。实验结果表明,采集仪能准确获得传感器的频率特性数据,并能实现一定频率范围内多个峰值信息的获取。再结合气体测量的相关模型,可直接输出参数测量结果,实现气体参数的自动检测。

关键词： Lamb波气体传感器直接数字频率合成幅相检测数据采集多峰值搜索

基于ECT和蚂蚁算法的油气两相流空隙率在线测量

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化工学报 2007年第1期58卷 61-66页

作者：李强伟黄志尧王保良李海青浙江大学控制科学与工程学系工业控制技术国家重点实验室浙江杭州310027

基于电容层析成像系统(ECT)和蚂蚁算法,提出了一种油气两相流空隙率在线测量的新方法。该方法利用电容层析成像系统12电极电容传感器所获取的66个测量电容信息,首先根据电容层析成像系统所获取的流型辨识结果确定对应流型下的实际空隙... 详细信息

基于电容层析成像系统(ECT)和蚂蚁算法,提出了一种油气两相流空隙率在线测量的新方法。该方法利用电容层析成像系统12电极电容传感器所获取的66个测量电容信息,首先根据电容层析成像系统所获取的流型辨识结果确定对应流型下的实际空隙率测量模型参数f和b,然后利用蚂蚁算法的信息素信息,找到当前测量状态下对空隙率起主要作用的组合电容集合和相应的权重系数,从而实现空隙率测量。与流型相对应的空隙率测量线性模型参数f和b基于先验数据通过最小二乘方法确定。油气两相流的实验结果表明,该方法对空隙率的在线测量是有效的,避免了复杂的图像重建计算,实时性能佳,测量时间小于0.08 s。在几种典型流型下,提出的空隙率测量方法与常用的快关阀方法相比最大测量偏差小于5.5%。

关键词：空隙率蚂蚁算法电容层析成像两相流流型