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The Design and Performance of a High Temperature Rise Combustor for Wind Tunnel

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Journal of Thermal Science 2011年第6期20卷 556-562页

作者： zhang Rongchun Fan weijun National Key Laboratory on Aero-Engines School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

A high-temperature-rise combustor that can be used in high-temperature wind tunnel is introduced in this *** kerosene is used in this type of combustor,with division combustion scheme and evaporator fuel-supply device *** the performance test under atmospheric pressure,when the inlet temperature is 500K and air flow is within the range of 1.5-3.0 kg/s,the outlet temperature can be precisely regulated within the range of ***,higher uniformity of outlet temperature distribution and higher combustion efficiency can be *** the long-time working in the wind tunnel,various components of the combustor,especially the combustor liners are checked without finding any anomaly such as thermal deformation.

关键词： high temperature rise evaporator wind tunnel combustor aviation kerosene

Simultaneous hybrid modeling of a nosiheptide fermentation process using particle swarm optimization

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Chinese Journal of Chemical Engineering 2016年第11期24卷 1631-1639页

作者： Qiangda Yang Hongbo Gao weijun zhang Huimin Li School of Metallurgy Northeastern University Shenyang 110819 China Department of Electromechanical Engineering Liaoning Provincial College of Communications Shenyang 110122 China

Hybrid modeling approaches have recently been investigated as an attractive alternative to model fermentation processes. Normally, these approaches require estimation data to train the empirical model part of a hybrid model. This may result in decreasing the generalization ability of the derived hybrid model. Therefore, a simultaneous hybrid modeling approach is presented in this paper. It transforms the training of the empirical model part into a dynamic system parameter identification problem, and thus allows training the empirical model part with only measured data. An adaptive escaping particle swarm optimization(AEPSO) algorithm with escaping and adaptive inertia weight adjustment strategies is constructed to solve the resulting parameter identification problem, and thereby accomplish the training of the empirical model part. The uniform design method is used to determine the empirical model structure. The proposed simultaneous hybrid modeling approach has been used in a lab-scale nosiheptide batch fermentation process. The results show that it is effective and leads to a more consistent model with better generalization ability when compared to existing ones. The performance of AEPSO is also demonstrated.

关键词： Bioprocess Dynamic modeling Neural networks Optimization

Optimal Operation with Dynamic Partitioning Strategy for Centralized Shared Energy Storage Station with Integration of Large-scale Renewable Energy

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 359-370页

作者： Jianlin Li Zhijin Fang Qian Wang Mengyuan zhang Yaxin Li weijun zhang Beijing Future Technology Innovation Centre for Electrochemical Energy Storage System Integration North China University of Technology Beijing China State Grid Fujian Electric Power Research Institute Fuzhou China

As renewable energy continues to be integrated into the grid,energy storage has become a vital technique supporting power system *** effectively promote the efficiency and economics of energy storage,centralized shared energy storage(SES)station with multiple energy storage batteries is developed to enable energy trading among a group of *** this paper,we propose the optimal operation with dynamic partitioning strategy for the centralized SES station,considering the day-ahead demands of large-scale renewable energy power *** implement a multi-entity cooperative optimization operation model based on Nash bargaining *** model is decomposed into two subproblems:the operation profit maximization problem with energy trading and the leasing payment bargaining *** distributed alternating direction multiplier method(ADMM)is employed to address the subproblems *** reveal that the optimal operation with a dynamic partitioning strategy improves the tracking of planned output of renewable energy entities,enhances the actual utilization rate of energy storage,and increases the profits of each participating *** results confirm the practicality and effectiveness of the strategy.

关键词： Shared energy storage(SES) dynamic partitioning strategy optimal operation Nash bargaining theory actual utilization rate of energy storage

Characterization of changes in extracellular polymeric substances and heavy metal speciation of waste activated sludge during typical oxidation solubilization processes

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Journal of Environmental Sciences 2019年第6期31卷 146-158页

作者： Qiongying Xu Huidi Wang Qiandi Wang weijun zhang Dongsheng Wang Faculty of Materials Science and Chemistry China University of Geosciences School of Environmental Studies China University of Geosciences Hubei Provincial Engineering Research Center of Systematic Water Pollution Control State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Biopolymer solubilization is considered to be the rate-limiting stage of anaerobic digestion of waste activated sludge(WAS). Oxidation processes have been proven to be effective in disrupting sludge flocs and causing solubilization of the solid biopolymers. In this study,WAS was treated by NaNO2 or H2 O2 oxidation at p H of 2. The changes in extracellular polymeric substances properties and the speciation of heavy metals were investigated. The results revealed that both NaNO2 and H2 O2 treatments were effective in solubilizing organics in WAS, while the conversion of biopolymers in the two treatment processes was different. Free nitrous acid destroyed the gel network structure of EPS, and organic materials were released from the solid phase to the supernatant. Indigenous peroxidase catalyzed H2 O2 to produce hydroxyl radicals which caused significant solubilization of biopolymers, and the protein-like substances were further degraded into micro-molecule polypeptides or amino acids at high dosages of H2 O2. During the oxidation processes, Zn, Cd and Cu, with excellent mobility, tended to migrate to the supernatant, and thus were easy to remove through the liquid–solid separation process. Ni and As showed moderate migration ability, of which the residual fraction tended to transform into reducible and soluble fractions. With poor mobility, Cr and Pb mainly existed in the forms of residual and oxidizable fractions, which were difficult to dissolve and remove from WAS. Both NaNO2 and H2 O2 treatment resulted in the enhancement of sludge solubilization efficiency and heavy metal mobility in WAS, but different heavy metals showed distinct migration and transformation behaviors.

关键词： Extracellular polymeric substances(EPS) Oxidation Biopolymers solubilization Biodegradability Heavy metals

Thermophysical properties of pure gases and mixtures at temperatures of 300-30000K and atmospheric pressure:thermodynamic properties and solution of equilibrium compositions

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Plasma Science and Technology 2021年第12期23卷 161-175页

作者： Zhongyuan CHI weijun zhang Qiangda YANG School of Metallurgy Northeastern UniversityShenyang 110819People's Republic of China

The equilibrium compositions and thermodynamic properties(density,enthalpy,etc at constant pressure)of plasma of pure gases and mixtures under local thermodynamic nonequilibrium have been calculated in this *** homotopy Levenberg-Marquardt algorithm was proposed to accurately solve nonlinear equations with singular Jacobian matrices,and is constructed by the Saha equation and Guldberg-Waage equation combined with mass conservation,the electric neutrality principle and Dalton’s partial pressure law,to solve the problem of dependence on the initial value in the process of iteration *** this research,the equations at a higher temperature were solved and used as the auxiliary equations,and the homotopy control parameters’sequence of the homotopy equations was selected by equal *** auxiliary equations,the iterative initial value was obtained by assuming that there were only the highestvalence atomic cations and electrons at this temperature,and the plasma equilibrium composition distribution with the required accuracy was ultimately solved under the current conditions employing the Levenberg-Marquardt *** control parameter sequence was arranged according to the geometric sequence and the homotopy step was gradually shortened to ensure continuity of the homotopy ***,the equilibrium composition and thermodynamic properties of pure N_(2),Mg(30%)-CO_(2)(70%)and Mg(40%)-CO(50%)-N_(2)(10%)mixture plasma at atmospheric pressure were calculated and the calculation process of some specified temperatures was shown and *** calculation accuracy of equilibrium composition is higher than other findings in the *** results for the thermodynamic properties are in good agreement with data reported by the literature.

关键词： plasma equilibrium compositions thermodynamic properties homotopy Levenberg-Marquardt algorithm(HLMA) auxiliary equations

Preparation of ultrahigh-surface-area sludge biopolymers-based carbon using alkali treatment for organic matters recovery coupled to catalytic pyrolysis

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Journal of Environmental Sciences 2021年第8期33卷 83-96页

作者： Yu zhang Jiayi Tang weijun zhang Jing Ai Yanyang Liu Qiandi Wang Dongsheng Wang School of Environmental Studies China University of GeosciencesWuhan 430074China Hubei Provincial Engineering Research Center of Systematic Water Pollution Control Wuhan 430074China Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco–Environmental SciencesChinese Academy of SciencesBeijing 100085China

In this work,we employed waste activated sludge(WAS)as carbon source to prepare ultrahigh specific surface area(SSA)biopolymers-based carbons(BBCs)through alkali(KOH)treatment coupled to pyrolysis *** the pyrolysis process,the involvement of KOH made a great recovery of soluble biopolymers from WAS,resulting in highly-efficient catalytic *** Brunner-Emmett-Teller and pore volume of BBCs prepared at 800℃(BBC800)reached the maximum at 2633.89 m2·g-1 and 2.919 m3·g-1,respectively.X-ray photoelectron spectroscopy suggested that aromatic carbon in the form of C=C was the dominant fraction of C element in *** N element in BBCs were composed of pyrrolic nitrogen and pyridinic nitrogen at 700℃,while a new graphitic nitrogen appeared over 800℃.As a refractory pollutant of wastewater treatment plants,tetracycline(TC)was selected to evaluate adsorption performance of *** adsorption behavior of BBCs towards TC was conformed to the pseudo-second-order kinetic and the Langmuir models,signifying that chemisorption of monolayers was dominant in TC *** adsorption capacity of BBC800 reached the maximum at 877.19 mg·g-1 for 90 min at 298 *** analysis indicated that the adsorption process was endothermic and *** bonding andπ-πstacking interaction were mainly responsible for TC adsorption,and interfacial diffusion was the main rate-control step in adsorption *** presence of sol-uble microbial products(SMPs)enhanced TC *** work provided a novel strategy to prepare bio-carbon with ultrahigh SSA using WAS for highly-efficient removal of organic pollutants.

关键词： Waste activated sludge Biopolymers-based carbons Adsorption Tetracycline

Effects of alkalinity on interaction between EPS and hydroxy-aluminum with different speciation in wastewater sludge conditioning with aluminum based inorganic polymer flocculant

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Journal of Environmental Sciences 2021年第2期33卷 257-268页

作者： weijun zhang Mingyue Tang Dandan Li Peng Yang Shiwei Xu Dongsheng Wang School of Environmental Studies China University of GeosciencesWuhan 430074China Hubei Provincial Engineering Research Center of Systematic Water Pollution Control Wuhan 430074China School of Civil and Architecture Engineer Northeast Electric Power UniuersityJilin 132012China CECEP Engineering Technology Research Institution Beijing 100082China

Extracellular polymeric substances(EPS)form a stable gel-like structure to combine with water molecules through steric hindrance,making the mechanical dewatering of wastewater sludge considerably ***/flocculation has been widely applied in improving the sludge dewatering performance,while sludge properties(organic fraction and solution chemistry conditions)are highly changeable and have important effects on sludge flocculation *** this work,the alkalinity effects on sludge conditioning with hydroxy-aluminum were comprehensively investigated,and the interaction mechanisms between EPS and hydroxy-aluminum with different speciation were *** results showed that the effectiveness of hydroxy-aluminum conditioning gradually deteriorated with increase in ***,the polymeric hydroxy-aluminum(Al 13)and highly polymerized hydroxy-aluminum(Al 30)were hydrolysed and converted into amorphous aluminum hydroxide(Al(OH)3),which changed the flocculation mechanism from charge neutralization and complexing adsorption to hydrogen bond ***,both Al 13 and Al 30 showed higher binding capacity for proteins and polysaccharides in EPS than monomeric aluminum and Al(OH)*** 13 and Al 30 coagulation changed the secondary structure of proteins in EPS,which caused a gelation reaction to increase molecular hydrophobicity of proteins and consequently sludge *** study provided a guidance for optimizing the hydroxy-aluminum flocculation conditioning of sludge with high solution alkalinity.

关键词： Coagulation/flocculation Hydroxy-aluminum Hydrolysis reaction Extracellular polymeric substances

Systematic assessment of dredged sludge dewaterability improvement with different organic polymers based on analytic hierarchy process

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Journal of Environmental Sciences 2021年第5期33卷 311-321页

作者： Zhenzhen Song Hongyu Gao Wanwan Liu Liqing Li weijun zhang Dongsheng Wang Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074HubeiChina State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Institute for resources and environmental engineering Shanxi UniversityTaiyuan 030006ShanxiChina School of Environmental Studies China University of GeosciencesWuhan 430074HubeiChina

Organic polymeric flocculants are commonly used in improving dredged sludge dewaterability, but less attention has been paid to residual water quality. In this paper, the effects of cationic etherified starch(CS) and poly-dimethyl diallyl ammonium chloride(PDDA) on dredged sludge dewatering efficiency and residual water quality of Baiyangdian lake were comprehensively investigated and evaluated by analytic hierarchy process(AHP). The results indicated that PDDA had stronger electrical effect and flocculation performance compared with CS, resulting in more efficient dewatering performance. PDDA can reduce the pollutants of discharged residual water, while CS significantly promoted the increase of NH_(4)^(+)-N and NO_(3)^(–)-N in the residual water. The increase of NH_(4)^(+)-N in the residual water of CS was due to the release of dredged sludge, while the increase of NO_(3)^(-)-N was introduced by CS leaching. AHP showed that PDDA performed better in flocculation treatment of dredged sludge than other organic polymers. This work provides a method for optimization of flocculation treatment for dredged sludge dewaterability.

关键词： Dredge sludge dewatering Flocculation evaluation model Residual water quality Analytic hierarchy process

Multitarget tracking control algorithm under local information selection interaction mechanism

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Intelligent and Converged Networks 2021年第2期2卷 91-100页

作者： Jiehong Wu Jinghui Yang weijun zhang Jiankai Zuo School of Computer Science Shenyang Aerospace UniversityShenyang 110136China Department of Computer Science and Technology Tongji UniversityShanghai 201804China

This study focuses on the problem of multitarget *** address the existing problems of current tracking algorithms,as manifested by the time consumption of subgroup separation and the uneven group size of unmanned aerial vehicles(UAVs)for target tracking,a multitarget tracking control algorithm under local information selection interaction is ***,on the basis of location,number,and perceived target information of neighboring UAVs,a temporary leader selection strategy is designed to realize the local follow-up movement of UAVs when the UAVs cannot fully perceive the ***,in combination with the basic rules of cluster movement and target information perception factors,distributed control equations are designed to achieve a rapid gathering of UAVs and consistent tracking of multiple ***,the simulation experiments are conducted in two-and three-dimensional *** a certain number of UAVs,clustering speed of the proposed algorithm is less than 3 s,and the equal probability of the UAV subgroup size after group separation is over 78%.

关键词： multitarget tracking time-consuming grouping local information selection interaction temporary leader selection strategy subgroup size