检索结果-南通市图书馆

Exergy Analysis of Charge and Discharge Processes of thermal Energy Storage System with Various Phase Change Materials:A Comprehensive Comparison

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of thermal Science 2024年第2期33卷 509-521页

作者： Mojtaba TAHERI Fathollah POURFAYAZ Roghayeh HABIBI Akbar MALEKI Department of renewable energies and Environment Faculty of New Sciences and TechnologiesUniversity of TehranTehran***Iran Faculty of Mechanical Engineering Shahrood University of TechnologyShahrood***Iran

thermal energy storage(TES) is of great importance in solving the mismatch between energy production and *** this regard,choosing type of Phase Change Materials(PCMs) which are widely used to control heat in latent thermal energy storage systems,plays a vital role as a means of TES ***,this field suffers from lack of a comprehensive investigation on the impact of various PCMs in terms of *** address this issue,in this study,in addition to indicating the melting temperature and latent heat of various PCMs,the exergy destruction and exergy efficiency of each material are estimated and compared with each ***,in the present work the impact of PCMs mass and ambient temperature on the exergy efficiency is *** results proved that higher latent heat does not necessarily lead to higher exergy ***,to obtain a suitable exergy efficiency,the specific heat capacity and melting temperature of the PCMs must also be *** to the results,LiF-CaF_(2)(80.5%:19.5%,mass ratio) mixture led to better performance with satisfactory exergy efficiency(98.84%) and notably lower required mass compared to other ***,the highest and lowest exergy destruction are belonged to GR25 and LiF-CaF_(2)(80.5:19.5) mixture,respectively.

关键词： exergy analysis phase change materials thermal energy storage exergy efficiency

维普期刊数据库

A review on the chemo-catalytic conversion of cellulose to bio-ethanol

在线全文

学校读者我要写书评

暂无评论

Green Chemical Engineering 2024年第3期5卷 276-289页

作者： Xiuzheng Zhuang Haiyong Wang Shugen Jiang Xiaohong Hu Tong Su Xinghua Zhang Longlong Ma Key laboratory of Energy thermal Conversion and Control of Ministry of Education School of Energy and Environment Southeast University Key laboratory of renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Wuzhou Refrigeration Group Co.Ltd.

While the industry has produced sugar-derived ethanol from the conventional method of fermentation for hundreds of years, other effective routes involving the direct transformation of carbohydrates still remain extremely rare. Very recently, an innovative chemo-catalytic method driven by the aqueous-phase catalysis was created for the synthesis of cellulosic ethanol, making a great breakthrough in the common ways as it can theoretically utilize all of the carbon atoms in sugars with faster kinetics; up to now, results from the relevant studies have been accumulated to a certain extent, but the periodic conclusions in this field are unfortunately absent. For this reason,this work tries to offer an overview of the cellulosic ethanol produced by chemo-catalytic routes, highlighting the present knowledge in relation to the technical efficiency, catalytic mechanisms as well as practical applications. At first, the advanced progress on the increasing efficiency from a varied type of catalytic systems are extensively discussed, which involves the specific functions of hybrid components from different strategies; meanwhile, the general influences of processing conditions, such as the hydrothermal severity and aqueous environments, are also identified. Subsequently, possible mechanisms behind the chemo-catalytic processes are widely elaborated by analyzing a number of experimental cases associated with the reaction network and its kinetic models. After that,the actual effects of this technique on the real biomass are collected to identify the positive/negative interactions between multiple components, together with the potential solutions on the semi-continuous processes of pilot scale application. The techno-economic analysis(TEA) is also calculated and compared with other similar methods, such as fermentation and gasification. Finally, several proposals aimed at upgrading the whole chain of chemo-catalytic processes are clearly provided, which may function as a guideline f

关键词： Cellulosic ethanol Chemo-catalytic method Influencing factors Catalytic mechanism Techno-economic analysis

Nanofluids:Critical issues,economics and sustainability perspectives

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第4期87卷 147-172页

作者： Sayantan Mukherjee Sylwia Wcislik Purna Chandra Mishra Paritosh Chaudhuri Instiute for Plasma Research Gandhinagar GujaratIndia Department of Building Physics and renewable Energy Faculy of Environmental EngineeringGeodesy and Renewable EnergyKielce University of TechnologyAleja Tysiaclecia Panstwa Polskiego 7.25-314 KielcePoland thermal Research laboratory(TRL) School of Mechanical Engineering.KIT Deemed to be UniversityBhubaneswarOdishaIndia Homi Bhabha National Instirute(HBNI) AnushaktinagarMumbai 400094India

According to the Scopus database,every year several hundreds of new research papers are published in the field of *** area is attracting growing attention because of the significant improvement in the heat transfer and energy efficiency of the systems working with ***,as results from numerous scientific studies conducted by independent laboratories,there are several fundamental problems related to the unambiguous determination of their physical properties,their production,and economic *** most studies often focus on one issue or cover one kind of research or math-ematical correlation,this review paper provides insights into many problems during nanofluids research by proposing solving possibilities,which is the strength of our *** paper discusses the case of nanofluids quality,and morphology,thermal conductivity enhancement and the discrepancies in mathematical modelling,errors in dimensional and similarity analysis,nanofluid erosion,safety guide-lines,and toxicology ***,the sustainability and economics of nanofluids usage are also being discussed.

关键词： Nanofluids thermal conductivity Stability Erosion Economics Sustainability

Numerical Assessment of the thermal Efficiency of a Concentrated Photovoltaic/thermal (CPV/T) Hybrid System Using Air as Heat Transfer Fluid

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Smart Grid and renewable Energy 2024年第1期15卷 1-14页

作者： Amadou Konfe Boureima Kabore Yves Christian Nonguierma Fatimata Ouedraogo Sié Kam laboratory of thermal and renewable energies University Joseph Ki-Zerbo Ouagadougou Burkina Faso Physic Department University Norbert Zongo Koudougou Burkina Faso Photonics and Nolinear Optics laboratory University of Moncton Moncton Canada

In this paper, we propose a thermal model of a hybrid photovoltaic/thermal concentration system. Starting from the thermal balance of the model, the equation is solved and simulated with a MATLAB code, considering air as the cooling fluid. This enabled us to evaluate some of the parameters influencing the electrical and thermal performance of this device. The results showed that the temperature, thermal efficiency and electrical efficiency delivered depend on the air mass flow rate. The electrical and thermal efficiencies for different values of air mass flow are encouraging, and demonstrate the benefits of cooling photovoltaic cells. The results show that thermal efficiency decreases air flow rate greater than 0.7 kg/s, whatever the value of the light concentration used. The thermal efficiency of the solar cell increases as the light concentration increases, whatever the air flow rate used. For a concentration equal to 30 sun, the thermal efficiency is 0.16 with an air flow rate equal to 0.005 kg/s;the thermal efficiency increases to 0.19 with an air flow rate equal to 0.1 kg/s at the same concentration. An interesting and useful finding was that the proposed numerical model allows the determination of the electrical as well as thermal efficiency of the hybrid CPV/T with air flow as cooling fluid.

关键词： PV Cell Concentrating thermal Energy Conversion Cooling Hybrid System

Customized modulation on plasma uniformity by non-uniform magnetic field in capacitively coupled plasma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第6期26卷 79-87页

作者：王森张权治马方方 Maksudbek YUSUPOV 王友年 School of Physics Dalian University of TechnologyDalian 116024People’s Republic of China laboratory of thermal Physics of Multiphase Systems Arifov Institute of Ion-Plasma and Laser TechnologiesAcademy of Sciences of UzbekistanTashkent 100125Uzbekistan Department of Power Supply and renewable Energy Sources National Research University TIIAMETashkent 100000Uzbekistan

A two-dimensional fluid model based on COMSOL Multiphysics is developed to investigate the modulation of static magnetic field on plasma homogeneity in a capacitively coupled plasma(CCP)chamber. To generate a static magnetic field, direct current is applied to a circular coil located at the top of the chamber. By adjusting the magnetic field's configuration, which is done by altering the coil current and position, both the plasma uniformity and density can be significantly modulated. In the absence of the magnetic field, the plasma density exhibits an inhomogeneous distribution characterized by higher values at the plasma edge and lower values at the center. The introduction of a magnetic field generated by coils results in a significant increase in electron density near the coils. Furthermore, an increase in the sets of coils improves the uniformity of the plasma. By flexibly adjusting the positions of the coils and the applied current,a substantial enhancement in overall uniformity can be achieved. These findings demonstrate the feasibility of using this method for achieving uniform plasma densities in industrial applications.

关键词： COMSOL capacitively coupled plasma plasma uniformity magnetic field

维普期刊数据库

Investigating the Impact of Base Heating and External Electric Field on PV Cell Performance under Intense Illumination

在线全文

学校读者我要写书评

暂无评论

Open Journal of Applied Sciences 2024年第5期14卷 1305-1314页

作者： Boubacar Soro Guy Serge Tchouadep Esso-Ehanam Tchedre Kpeli Ousmane Souliga Adama Ouedraogo Issa Zerbo Martial Zoungrana laboratory of thermal and renewable energies Universit&#233 Joseph KI-ZERBO Ouagadougou Burkina Faso Institut des Sciences et Technologie Ecole Normale Sup&#233rieure Ouagadougou Burkina Faso

The characterization of the performances of a PV cell is linked to intrinsic factors of this cell. It is therefore important for us to identify the favorable or unfavorable conditions that affect the performance of PV cells. It is from this perspective that it seems judicious to us to study the simultaneous influence of the heating of the base and an external electric field on the performance of a PV cell under intense illumination of 50 suns. Two phenomena contribute to the heating of the base of a PV cell which is heating due to the transfer by conduction of solar radiation energy received by the surface of the PV cell and the heat generated inside the PV cell by various phenomena linked to the movement of photogenerated charged carriers. In this study, we take into account the heating linked to the movement of the charged carriers in the base. After a mathematical modeling of the PV cell considered, some hypotheses are formulated and the expressions of the electrical parameters are established as a function of the electric field and base temperature. Subsequently, we use numerical simulation to highlight the behavior of theses parameters as a function of temperature and of the intensity of the electric field. The results show that for any given temperature, the orientation of the electric field as considered in our work improves the performance of the PV cell while high temperatures degrade these performances. Furthermore, the analysis of the curves shows that the harmful effect of temperature on the performance of a PV cell is more accentuated at large values of electric field.

关键词： Collisions thermalization Braking Electric Strength Base Temperature

Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-Fei Guo Ze-Long Liang Yue-E Jiao Hang Xu Bin Zhao Key laboratory of Advanced Energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,*** studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction ***,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild *** corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale ***,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air ***,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@*** investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal *** importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

维普期刊数据库

Cascade utilization of full spectrum solar energy for achieving simultaneous hydrogen production and all-day thermoelectric conversion

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第9期96卷 318-327页

作者： Tuo Zhang Liang Dong Baoyuan Wang Jingkuo Qu Xiaoyuan Ye Wengao Zeng Ze Gao Bin Zhu Ziying Zhang Xiangjiu Guan Liejin Guo International Research Center for renewable Energy(IRCRE) State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina

Solar-driven photocatalytic water/seawater splitting holds great potential for green hydrogen ***,the practical application is hindered by the relatively low conversion efficiency resulting from the inadequate utilization of solar spectrum with significant waste in the form of ***,current equipment struggles to maintain all-day operation subjected to the lack of light during ***,a novel hybrid system integrating photothermal catalytic(PTC)reactor,thermoelectric generator(TEG),and phase change materials(PCM)was proposed and designed(named as PTC-TEG-PCM)to address these challenges and enable simultaneous overall seawater splitting and 24-hour power *** PTC system effectively maintains in an optimal temperature range to maximize photothermal-assisted photocatalytic hydrogen *** TEG component recycles the low-grade waste heat for power generation,complementing the shortcoming of photocatalytic conversion and achieving cascade utilization of full-spectrum solar ***,exceptional thermal storage capability of PCM allow for the conversion of released heat into electricity during nighttime,contributing significantly to the overall power output and enabling PTC-TEG-PCM to operate for more than 12 h under the actual *** to traditional PTC system,the overall energy conversion efficiency of the PTC-TEG-PCM system can be increased by∼500%,while maintaining the solar-to-hydrogen *** advancement of this novel system demonstrated that recycling waste heat from the PTC system and utilizing heat absorption/release capability of PCM for thermoelectric application are effective strategies to improve solar energy *** flexible parameter designing,PTC-TEG-PCM can be applied in various scenarios,offering high efficiency,stability,and sustainability.

关键词： Hybrid solar energy conversion system Photocatalytic overall seawatersplitting Thermoelectric power generation Phase change materials All-day operation

Assessment and Enhancement of FRC of Power Systems Considering thermal Power Dynamic Conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第4期10卷 1371-1383页

作者： Feng Hong Yalei Pang Weiming Ji Lu Liang Fang Fang Junhong Hao Jizhen Liu State Key laboratory of Alternate Electric Power System with renewable Energy Sources and School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China State Key laboratory of Alternate Electric Power System with renewable Energy Sources School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China

Frequency stability and security have been a vital challenge as large-scale renewable energy is integrated into power *** contrast,the proportion of traditional thermal power units decreases during the decarbonization transformation process,resulting in poor frequency *** paper aims to explore the potential of frequency regulation support,dynamic assessment,and capacity promotion of thermal power plants in the transition *** the dynamic characteristics of the main steam working fluid under different working conditions,a nonlinear observer is constructed by extracting the main steam pressure and valve opening degree *** real-time frequency modulation capacity of thermal power units can provide a dynamic state for the power grid.A dynamic adaptive modification for primary frequency control(PFC)of power systems,including wind power and thermal power,is proposed and *** power dynamic allocation factor is adaptively optimized by predicting the speed droop ratio,and the frequency modulation capability of the system is improved by more than 11%under extreme ***,through the Monte Carlo simulation of unit states of the system under various working conditions,the promotion of the frequency regulation capacity with high wind power penetration(WPP)is verified.

关键词： Dynamic evaluation frequency regulation power system predictive modeling wind penetration