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Finite Difference Solution of Response Time Delay of Magneto-rhelological Damper

Chinese Journal of Mechanical Engineering 2009年第3期22卷 446-450页

作者： ZOU Mingsong hou baolin School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China

Magneto-rhelological（MR） dampers are devices that employ rheological fluids to modify their mechanical properties. Their mechanical simplicity, high dynamic range, lower power requirements, large force capacity, robustness and safe maimer of operation in cases of failure have made them attractive devices for semi-active real-time control in civil, aerospace and automotive applications. Time response characteristic is one of the most important technical performances of MR dampers, and response time directly affects the control frequency, application range and the actual effect of MR dampers. In this study, one kind of finite difference solution for predicting the response time ofmagneto-rheological dampers from ＂off-state＂ to ＂on-state＂ is put forward. A laminar flow model is used to describe the flow in the MR valve, and a bi-viscous fluid flow model is utilized to describe the relationship of shear stress and shear rate of MR fluid. An explicit difference format is used to diseretize the Novior-Stoks equation, and stability condition of this algorithm is built by Von-Neumann stability criterion. The pressure gradient along the flow duct is solved by a dichotomy algorithm with iteration, and the changing curve of the damping force versus time of MR damper is obtained as well. According to the abovementioned numerical algorithm, the damping forces versus time curves from ＂off-state＂ to ＂on-state＂ of a cylindrical piston type MR damper are computed. Moreover, the MR damper is installed in a material test system（MTS）, the magnetic field in the wire circles of the MR damper is ＂triggered＂ when the MR damper is imposed to do a constant speed motion, and the damping force curves are recorded. The comparison between numerical results and experimental results indicates that this finite difference algorithm can be used to estimate the response time delay of MR dampers.

关键词： magneto-rheological damper response time finite difference method

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Quantitative structure–biodegradability relationships for biokinetic parameter of polycyclic aromatic hydrocarbons

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Journal of Environmental Sciences 2015年第4期27卷 180-185页

作者： Peng Xu Wencheng Ma Hongjun Han Shengyong Jia baolin hou State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

Prediction of the biodegradability of organic pollutants is an ecologically desirable and economically feasible tool for estimating the environmental fate of chemicals. In this paper,stepwise multiple linear regression analysis method was applied to establish quantitative structure biodegradability relationship（QSBR） between the chemical structure and a novel biodegradation activity index（qmax） of 20 polycyclic aromatic hydrocarbons（PAHs）. The frequency B3LYP/6-311＋G（2df,p） calculations showed no imaginary values, implying that all the structures are minima on the potential energy surface. After eliminating the parameters which had low related coefficient with qmax, the major descriptors influencing the biodegradation activity were screened to be Freq, D, MR, EHOMOand To IE. The evaluation of the developed QSBR mode, using a leave-one-out cross-validation procedure, showed that the relationships are significant and the model had good robustness and predictive ability. The results would be helpful for understanding the mechanisms governing biodegradation at the molecular level.

关键词： Leave-one-out cross-validation Stepwise multiple linear regression Polycyclic aromatic hydrocarbons QSBR

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A CFD model for predicting the heat transfer in the industrial scale packed bed

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Chinese Journal of Chemical Engineering 2018年第2期26卷 228-237页

作者： baolin hou Renming Ye Yanqiang Huang Xiaodong Wang Tao Zhang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences

Compared to the traditional lumped-parameter model, computational fluid dynamics （CFD） attracted more attentions due to facilitating more accurate reactor design and optimization methods when analyzing the heat transfer in the industrial packed bed. Here, a model was developed based on the CFD theory, in which the heterogeneous fluid flow was resolved by considering the oscillatory behavior of voidage and the effective fluid viscosity. The energy transports in packed bed were calculated by the convection and diffusion incorporated with gaseous dispersion in fluid and the contacting thermal conductivity of packed particles in solids. The heat transfer coefficient between fluid and wall was evaluated by considering the turbulence due to the packed particles adjacent to the wall. Thus, the heat transfer in padded bed can be predicted without using any adjustable semi-empirical effective thermal conductivity coefficient. The experimental results from the literature were employed to validate this model.

关键词： JHeat transferPacked bedComputational fluid dynamics (CFD)

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Advanced treatment of biologically pretreated coal gasification wastewater by a novel heterogeneous Fenton oxidation process

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Journal of Environmental Sciences 2015年第7期27卷 12-20页

作者： Haifeng Zhuang Hongjun Han Wencheng Ma baolin hou Shengyong Jia Qian Zhao State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

Sewage sludge from a biological wastewater treatment plant was converted into sewage sludge based activated carbon（SBAC） with Zn Cl2 as activation agent, which was used as a support for ferric oxides to form a catalyst（Fe Ox/SBAC） by a simple impregnation *** new material was then used to improve the performance of Fenton oxidation of real biologically pretreated coal gasification wastewater（CGW）. The results indicated that the prepared Fe Ox/SBAC significantly enhanced the pollutant removal performance in the Fenton process, so that the treated wastewater was more biodegradable and less toxic. The best performance was obtained over a wide p H range from 2 to 7, temperature 30°C, 15 mg/L of H2O2 and 1 g/L of catalyst, and the treated effluent concentrations of COD, total phenols,BOD5 and TOC all met the discharge limits in China. Meanwhile, on the basis of significant inhibition by a radical scavenger in the heterogeneous Fenton process as well as the evolution of FT-IR spectra of pollutant-saturated Fe Ox/BAC with and without H2O2, it was deduced that the catalytic activity was responsible for generating hydroxyl radicals, and a possible reaction pathway and interface mechanism were proposed. Moreover, Fe Ox/SBAC showed superior stability over five successive oxidation runs. Thus, heterogeneous Fenton oxidation of biologically pretreated CGW by Fe Ox/SBAC, with the advantages of being economical, efficient and sustainable, holds promise for engineering application.

关键词： Biologically pretreated coal gasification wastewater Heterogeneous Fenton oxidation Catalyst Biodegradability Mechanism

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Effect of alkalinity on nitrite accumulation in treatment of coal chemical industry wastewater using moving bed biofilm reactor

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Journal of Environmental Sciences 2014年第5期26卷 1014-1022页

作者： baolin hou Hongjun Han Shengyong Jia Haifeng Zhuang Qian Zhao Peng Xu State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

Nitrogen removal via nitrite （the nitrite pathway） is more suitable for carbon-limited industrial wastewater. Partial nitrification to nitrite is the primary step to achieve nitrogen removal via nitrite. The effect of alkalinity on nitrite accumulation in a continuous process was investigated by progressively increasing the alkalinity dosage ratio （amount of alkalinity to ammonia ratio, mol/mol）. There is a close relationship among alkalinity, pH and the state of matter present in aqueous solution. When alkalinity was insufficient （compared to the theoretical alkalinity amount）, ammonia removal efficiency increased first and then decreased at each alkalinity dosage ratio, with an abrupt removal efficiency peak. Generally, ammonia removal efficiency rose with increasing alkalinity dosage ratio. Ammonia removal efficiency reached to 88% from 23% when alkalinity addition was sufficient. Nitrite accumulation could be achieved by inhibiting nitrite oxidizing bacteria （NOB） by free ammonia （FA） in the early period and free nitrous acid in the later period of nitrification when alkalinity was not adequate. Only FA worked to inhibit the activity of NOB when alkalinity addition was sufficient.

关键词： alkalinity nitritation coal chemical industry wastewater moving bed biofilm reactor

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Fast Smooth Second-Order Sliding Mode Control with Disturbance Observer for Automatic Shell Magazine

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Journal of Shanghai Jiaotong university(Science) 2021年第6期26卷 847-856页

作者： YAO Laipeng hou baolin LIU Xi School of Mechanical Engineering Changshu Institute of TechnologySuzhou 215500JiangsuChina School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

This paper studies practical control design for a novel automatic shell magazine(ASM)with a new fast smooth second-order sliding mode(FSSOSM)control based on disturbance *** dynamic model of the ASM with parameter perturbations and nonlinear friction is established.A higher order sliding mode disturbance observer based on super-twisting algorithm is utilized as a robust compensator to estimate the lumped *** proposed FSSOSM control is performed to obtain the continuous sliding mode control law and inhibit the chattering *** finite time convergence is investigated by utilizing the Lyapunov stability *** controllers,the traditional sliding mode controller,the proposed FSSOSM controller and a continuous fixed-time second-order sliding mode(CFTSOSM)controller,are *** comparative simulation results under three typical working conditions(no-loaded,half-loaded and full-loaded)demonstrate that the proposed control strategy has a high dynamic tracking performance along with a good robustness against model uncertainty.

关键词： nonlinear systems model uncertainty disturbance observer finite-time convergence sliding mode control

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Nitrogen removal from coal gasification wastewater by activated carbon technologies combined with short-cut nitrogen removal process

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Journal of Environmental Sciences 2014年第11期26卷 2231-2239页

作者： Qian Zhao Hongjun Han baolin hou Haifeng Zhuang Shengyong Jia Fang Fang State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal （GAC-PACT-SBNR） was developed to enhance total nitrogen （TN） removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The TN removal efficiency in SBNR was significantly improved by introducing the effluent from the GAC process into SBNR during the anoxic stage, with removal percentage increasing from 43.8%49.6% to 68.8%-75.8%. However, the TN removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAG compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the TN removal rate in SBNR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand （COD） degradation by autotrophic bacteria in SBNR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance TN removal in coal gasification wastewater （CGW）.

关键词： Coal gasification wastewater Short-cut nitrogen removal Granular activated carbon PCR-DGGE Denitrification enhancement

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Anoxic degradation of nitrogenous heterocyclic compounds by activated sludge and their active sites

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Journal of Environmental Sciences 2015年第5期27卷 221-225页

作者： Peng Xu Hongjun Han Haifeng Zhuang baolin hou Shengyong Jia Dexin Wang Kun Li Qian Zhao State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

The potential for degradation of five nitrogenous heterocyclic compounds（NHCs）, i.e.,imidazole, pyridine, indole, quinoline, and carbazole, was investigated under anoxic conditions with acclimated activated sludge. Results showed that NHCs with initial concentration of 50 mg/L could be completely degraded within 60 hr. The degradation of five NHCs was dependent upon the chemical structures with the following sequence：imidazole 〉 pyridine 〉 indole 〉 quinoline 〉 carbazole in terms of their degradation *** structure-biodegradability relationship studies of the five NHCs showed that the anoxic degradation rates were correlated well with highest occupied molecular ***, the active sites of NHCs identified by calculation were confirmed by analysis of intermediates using gas chromatography and mass spectrometry.

关键词： Anoxic NHCs Pseudo first-order equation

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机构动作可靠性估计的自适应极值响应面法

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哈尔滨工程大学学报 2024年第3期45卷 581-589页

作者：文浩侯保林南京理工大学机械工程学院江苏南京210094

针对存在随机-区间混合不确定性的机构动作可靠性估计问题,本文提出了一种基于自适应极值响应面的高效计算方法,将其转化为随机不确定性下的动作可靠度上下界求解问题。使用麻雀搜索算法优化的混合核极限学习机构建从混合不确定性变量... 详细信息

针对存在随机-区间混合不确定性的机构动作可靠性估计问题,本文提出了一种基于自适应极值响应面的高效计算方法,将其转化为随机不确定性下的动作可靠度上下界求解问题。使用麻雀搜索算法优化的混合核极限学习机构建从混合不确定性变量到极限状态函数响应值的初始响应面和从随机变量到极限状态函数响应极值的极值响应面;利用结合主动学习与反向学习的自适应加点策略选取极限状态曲面附近的样本点更新极值响应面以提高其精度与效率;最后结合极值响应面和蒙特卡罗仿真算得到动作可靠度上下界的近似解。通过数值案例和回转链式输送机的工程案例对所提自适应极值响应面方法的高效性与准确性进行了验证,为随机-区间混合不确定性下的机构动作可靠性估计提供了一种参考。

关键词：动作可靠性混合不确定性极值响应面自适应加点策略混合核极限学习机麻雀搜索算法主动学习反向学习

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FDA与ML-KELM结合的机电系统故障识别

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哈尔滨工业大学学报 2023年第8期55卷 106-115页

作者：文浩侯保林南京理工大学机械工程学院南京210094

为准确识别坦克自动装弹机中的机电系统故障,提出了一种结合函数型数据分析(Functional data analysis,FDA)和多层核极限学习机(Multi-layer kernel extreme learning machine,ML-KELM)的故障识别方法。首先,以函数的视角对机电系统运... 详细信息

为准确识别坦克自动装弹机中的机电系统故障,提出了一种结合函数型数据分析(Functional data analysis,FDA)和多层核极限学习机(Multi-layer kernel extreme learning machine,ML-KELM)的故障识别方法。首先,以函数的视角对机电系统运行过程中具有平滑特性的时序数据进行特征信息挖掘,利用函数型主成分分析和主微分分析从不同空间将时序数据的变化特性表征为特征参数;其次,对提取的多传感器时序数据的特征进行Relief-F特征筛选,得到与分类强相关的特征;最后,采用ML-KELM对强相关特征进行深度特征学习,获取更抽象的特征表达,进而实现准确的故障识别。结果表明:采用与某坦克自动装弹机中的链式输送机原理一致的实验装置进行故障识别实验,函数型主成分分析和主微分分析能够从不同的特征空间中提取时序数据中的有效故障特征,并且两种方法提取的特征具有互补性;基于多传感器时序数据特征中的强相关特征,使用3层隐含层的ML-KELM能够实现较为准确的故障识别,所提方法具有可行性和有效性,为坦克自动装弹机中的机电系统故障识别的研究提供了一种参考。

关键词：故障识别特征提取函数型主成分分析主微分分析多层核极限学习机时序数据

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