European Physical Journal-applied Physics最新文献_第7页

Model, simulation and experiments for a Buoyancy Organic Rankine Cycle 浮力有机朗肯循环的模型、模拟与实验

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-10-01 DOI: 10.1051/epjap/2020200113

J. Schoenmaker, P. Martins, Guilherme Silva, Júlio, Carlos J C Teixeira

{"title":"Model, simulation and experiments for a Buoyancy Organic Rankine Cycle","authors":"J. Schoenmaker, P. Martins, Guilherme Silva, Júlio, Carlos J C Teixeira","doi":"10.1051/epjap/2020200113","DOIUrl":"https://doi.org/10.1051/epjap/2020200113","url":null,"abstract":"Organic Rankine Cycle (ORC) systems are increasingl y gaining relevance in the renewable and sustainable energy scenario. Recently our research group published a manuscript identifying a new type of thermodynamic cycle entitled Buoyancy Organ ic Rankine Cycle (BORC) (Schoenmaker et al., 2011). In this work we present two main contribut ions. First, we propose a refined thermodynamic model for BORC systems accounting for the specific heat of the working fluid. Considering the refined model, the efficiencies for Pentane and Dic hloromethane at temperatures up to 100°C were estimated to be 17.2%. Second, we show a proof of c oncept BORC system using a 3 m tall, 0,062 m diameter polycarbonate tube as a column-fluid reser voir. We used water as a column fluid. The thermal stability and uniformity throughout the tub e has been carefully simulated and verified experimentally. After the thermal parameters of the water column have been fully characterized, we developed a test body to allow an adequate assessme nt of the BORC-system’s efficiency. We obtained 0,84% efficiency for 43,8oC working temper atu e. This corresponds to 35% of the Carnot efficiency calculated for the same temperature diff erence. Limitations of the model and the apparatus are put into perspective, pointing directions for f urther developments of BORC systems.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":"8 1","pages":"10906"},"PeriodicalIF":1.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76269733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A miniaturized gas flow energy harvester using diamagnetically stabilized levitation 一种采用抗磁稳定悬浮的小型气流能量采集器

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-10-01 DOI: 10.1051/epjap/2020200059

Kun Zhang, Qi Gong, Xia Li, Yufeng Su, Z. Duan

{"title":"A miniaturized gas flow energy harvester using diamagnetically stabilized levitation","authors":"Kun Zhang, Qi Gong, Xia Li, Yufeng Su, Z. Duan","doi":"10.1051/epjap/2020200059","DOIUrl":"https://doi.org/10.1051/epjap/2020200059","url":null,"abstract":"In this paper, a miniaturized energy harvester is presented to scavenge gas flow energy. A magnet rotor with three teeth evenly distributed on the edge was introduced into the energy harvester, and it is frictionlessly levitated between two highly oriented pyrolytic graphite (HOPG) sheets. The energy harvester is designed to operate at a single stable equilibrium, so as to improve the stability of the rotor. The optimal incident angle of the gas flow was determined to be 83°. On the basis of the optimal angle, two different configurations of the energy harvester were proposed. Configuration A includes one nozzle, while Configuration B has two centrosymmetric nozzles. The maximum flow rate that enables Configurations A to work stably is limited, which can be increased by thickening the magnet rotor. The maximum voltage of configuration A was 0.28 V at a flow rate of 1500 sccm for the 4.5 mm thick rotor. Configuration B can run stably at any flow rate bigger than 250 sccm and the induced voltage increases with the driving flow rate. At the flow rate of 3000 sccm, the energy harvester of Configuration B can generate a maximum voltage of 3 V and light up tens of light-emitting-diodes (LEDs).","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":"1 1","pages":"10903"},"PeriodicalIF":1.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79927952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Natural convection analysis flow of Al2O3-Cu/water hybrid nanofluid in a porous conical enclosure subjected to the magnetic field 磁场作用下Al2O3-Cu/水混合纳米流体在多孔锥形外壳中的自然对流流动分析

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-08 DOI: 10.1051/epjap/2020200260

R. Slimani, A. Aissa, Fateh Mebarek-oudina, Umair Khan, M. Sahnoun, Ali J. Chamkha, M. Medebber

{"title":"Natural convection analysis flow of Al2O3-Cu/water hybrid nanofluid in a porous conical enclosure subjected to the magnetic field","authors":"R. Slimani, A. Aissa, Fateh Mebarek-oudina, Umair Khan, M. Sahnoun, Ali J. Chamkha, M. Medebber","doi":"10.1051/epjap/2020200260","DOIUrl":"https://doi.org/10.1051/epjap/2020200260","url":null,"abstract":"The current study investigates MHD natural convection heat transfer of a hybrid nanofluid in a truncated cone along with transparent domains having the stimulus of an inherent constant magnetic field. The governing equations subject to the physical boundary conditions are solved numerically by using the Galerkin finite element method. The effects of the various parameters involved in the problem such as the Rayleigh number Ra (ranging between 103 and 106 ), the Hartmann number Ha (ranging between 0 and 60), and the porosity ratio e (0.1–0.9) are examined. Moreover, the effects of Da which represents the Darcy number (between 10‑3 and 10‑1 ) and the volume fraction of nanoparticles ϕ for the dissipated nanoparticles of Al2 O3- Cu are reported in terms of the streamlines and isotherms distributions as well as the Nusselt number. Such parameters are critical control parameters for both the fluid flow and the rate of heat transfer of the natural convection in the annular space. The solution outcomes proof that the average Nusselt number varies directly with the dynamic field flowing through a porous media, whereas it behaves inversely with the magnetic field.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":"34 1","pages":"10904"},"PeriodicalIF":1.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75414382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 30

Mean multiplication gain and excess noise factor of GaN and Al0.45Ga0.55N avalanche photodiodes GaN和Al0.45Ga0.55N雪崩光电二极管的平均倍增增益和多余噪声系数

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-03 DOI: 10.1051/epjap/2020200067

Tat Lung Wesley Ooi, P. L. Cheang, A. You, Y. Chan

{"title":"Mean multiplication gain and excess noise factor of GaN and Al0.45Ga0.55N avalanche photodiodes","authors":"Tat Lung Wesley Ooi, P. L. Cheang, A. You, Y. Chan","doi":"10.1051/epjap/2020200067","DOIUrl":"https://doi.org/10.1051/epjap/2020200067","url":null,"abstract":"In this work, Monte Carlo model is developed to investigate the avalanche characteristics of GaN and Al0.45 Ga0.55 N avalanche photodiodes (APDs) using random ionization path lengths incorporating dead space effect. The simulation includes the impact ionization coefficients, multiplication gain and excess noise factor for electron- and hole-initiated multiplication with a range of thin multiplication widths. The impact ionization coefficient for GaN is higher than that of Al0.45 Ga0.55 N. For GaN, electron dominates the impact ionization at high electric field while hole dominate at low electric field whereas Al0.45 Ga0.55 N has hole dominate the impact ionization at higher field while electron dominate the lower field. In GaN APDs, electron-initiated multiplication is leading the multiplication gain at thinner multiplication widths while hole-initiated multiplication leads for longer widths. However for Al0.45 Ga0.55 N APDs, hole-initiated multiplication leads the multiplication gain for all multiplication widths simulated. The excess noise of electron-initiated multiplication in GaN APDs increases as multiplication widths increases while the excess noise decreases as the multiplication widths increases for hole-initiated multiplication. As for Al0.45 Ga0.55 N APDs, the excess noise for hole-initiated multiplication increases when multiplication width increases while the electron-initiated multiplication increases with the same gradient at all multiplication widths.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":"35 1","pages":"10301"},"PeriodicalIF":1.0,"publicationDate":"2020-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86827138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Substrate temperature effect on structural, electronic and optical properties of V2O5 thin films: experimental and ab initio study 衬底温度对V2O5薄膜结构、电子和光学性能的影响:实验和从头计算研究

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-03 DOI: 10.1051/epjap/2020200154

R. Temsamani, A. Talbi, A. Mrigal, M. Addou, K. Nouneh, Karima Guedouch, H. Zaari

引用次数: 1

Strong high-frequency spin waves released periodically from a confined region 周期性地从受限区域释放出强高频自旋波

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-01 DOI: 10.1051/epjap/2020200144

Zhen-wei Zhou, Xi-guang Wang, Yao Nie, Q. Xia, G. Guo

引用次数: 1

The anisotropic optical properties of different polytypes (ε, β, δ, γ) of GaSe lamellar materials 不同多型(ε， β， δ， γ) GaSe片层材料的各向异性光学性质

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-01 DOI: 10.1051/epjap/2020200136

M. Al-Hattab, L. Moudou, Y. Chrafih, M. Khenfouch, O. Bajjou, K. Rahmani

{"title":"The anisotropic optical properties of different polytypes (ε, β, δ, γ) of GaSe lamellar materials","authors":"M. Al-Hattab, L. Moudou, Y. Chrafih, M. Khenfouch, O. Bajjou, K. Rahmani","doi":"10.1051/epjap/2020200136","DOIUrl":"https://doi.org/10.1051/epjap/2020200136","url":null,"abstract":"In this paper, we have calculated the optical properties of the different polytypes of GaSe lamellar materials. The calculations are based on the DFT method and is performed using the CASTEP code. All optical properties have been studied in a domain that extends energetically from 10 meV to 35 eV and have been measured for a polarization // and ⊥ with the c axis. A strong anisotropic was observed, which indicates that the optical properties of the GaSe material are essentially determined by the symmetry of a single layer, exactly by the symmetry resulting from the stacking of the layers. Moreover, the absorption starts in the UV–vis spectral range, the peaks appear in the UV range. The refractive index values are n xx = 2.54, 2.55, 2.88, 10.85, n zz = 3.90, 3.90, 3.26, 11.73 for e , β , γ , δ , respectively at zero photon energy. Furthermore, we notice that the optical properties of different polytypes (e , β , δ , γ ) of GaSe lamellar materials are obtained both in the ultraviolet field or in the visible domain are significant and give a strong argument for the use of these materials in various applications, namely photovoltaic cells, nanoelectronic, optoelectronic, optical fiber and photo-catalytic applications.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":"134 1","pages":"30102"},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88244690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Evidence for electron-tunneling-limited Knudsen diffusion of mercury in phosphor layers and coatings of fluorescent lamps 荧光灯荧光粉层和涂层中汞的电子隧道限制克努森扩散的证据

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-01 DOI: 10.1051/epjap/2020190286

R. Tidecks

引用次数: 0

Experimental study on the evaporating progress of hexane lenses on water surface with different temperature 不同温度下正己烷透镜在水面蒸发过程的实验研究

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-01 DOI: 10.1051/epjap/2020200163

Aiqiang Chen, Xin Chen, X. Miao, Jinghong Yin, B. Liu

引用次数: 1

One pot synthesis of silver nanoparticles on ITO surfaces: investigation of optical and electrochemical properties 一锅法在ITO表面合成银纳米粒子:光学和电化学性质的研究

IF 1 4区物理与天体物理

European Physical Journal-applied Physics Pub Date : 2020-09-01 DOI: 10.1051/epjap/2020200130

Nadia El Harfaouia, Y. Khaaissa, K. Nouneh, A. Belahmar, A. Talbi, K. El Mabrouk, R. Hsissou, E. Feddi, A. Taleb, A. El Mouakibi

{"title":"One pot synthesis of silver nanoparticles on ITO surfaces: investigation of optical and electrochemical properties","authors":"Nadia El Harfaouia, Y. Khaaissa, K. Nouneh, A. Belahmar, A. Talbi, K. El Mabrouk, R. Hsissou, E. Feddi, A. Taleb, A. El Mouakibi","doi":"10.1051/epjap/2020200130","DOIUrl":"https://doi.org/10.1051/epjap/2020200130","url":null,"abstract":"Dense layer of silver nanoparticles (AgNPs) was successfully prepared on indium tin oxide (ITO) surfaces by using a refined seed-mediated growth approach (RSMG). Prepared AgNPs/ITO film was investigated using several methods such as UV–vis spectroscopy, field emission scanning electron microscope, optical absorption, electrochemical impedance spectroscopy and cyclic voltammeter. The size and density of AgNPs on ITO surface were investigated and their governing parameters were discussed. The obtained results by using refined seed-mediated growth approach showed a narrower size distribution and a higher density of prepared AgNPs compared to those prepared by the normal seed-mediated growth method. The size of AgNPs was controlled by adjusting the growth time until 2 h, while if it is higher than 3 h, larger AgNPs with anisotropic shape were formed. Cysteamine molecules were used to ensure the attachment of AgNPs on the ITO surface and it was found to be effective for preparing dense and dispersed Ag NPs on ITO surface. The optical properties of prepared AgNPs layer with different density on the ITO surface were studied and discussed, using the full Mie theory for scattering and absorption by a homogeneous Ag sphere with modified dielectric constants.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":"41 1","pages":"30401"},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88042778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10