Annals of West Univesity of Timişoara最新文献

Thermal Performance of Double Pass Solar Air Collector: Numerical and Experimental Investigation 双通道太阳能空气集热器的热性能:数值与实验研究

Annals of West Univesity of Timişoara Pub Date : 2023-11-10 DOI: 10.2478/awutp-2023-0010

Yousef Belloufi, Amar Rouag, Faris Aissaoui, Abdelmoumene-Hakim Benmachiche, Abdelhfid Brima

引用次数: 0

Experimental and Hybrid Numerical Analytical Approach of an Earth-to-Air Heat Exchanger 土-空气换热器的实验与混合数值分析方法

Annals of West Univesity of Timişoara Pub Date : 2023-11-10 DOI: 10.2478/awutp-2023-0008

Faris Aissaoui, Amar Rouag, Yousef Belloufi, Sakina Zerouali, Rachid Atmani, Adel Benchabane, Abdelhafid Brima, Noureddine Moummi, Djamel Belatrache

{"title":"Experimental and Hybrid Numerical Analytical Approach of an Earth-to-Air Heat Exchanger","authors":"Faris Aissaoui, Amar Rouag, Yousef Belloufi, Sakina Zerouali, Rachid Atmani, Adel Benchabane, Abdelhafid Brima, Noureddine Moummi, Djamel Belatrache","doi":"10.2478/awutp-2023-0008","DOIUrl":"https://doi.org/10.2478/awutp-2023-0008","url":null,"abstract":"Abstract The primary goal of this paper is to assess the thermal behaviour of Earth-to-Air Heat Exchanger (EAHE) under continuous operation mode during the cooling period in warm climatic conditions. An experimental setup was conducted in Biskra University (Algeria) to test the ability to use EAHE as an alternative solution to conventional air conditioning systems. Besides, a transient numerical approach for the flowing air within the EAHE was developed using energy balance equations, discretised by the implicit finite differences method and solved by Thomas method. Furthermore, the transient temperature profile of the soil around the EAHE was investigated in order to determine the adiabatic radius of the soil as a function of the duration of operation. In this context, a transient semi-analytical model was integrated to the air model to estimate the transient EAHE’s performance deterioration. This deterioration is produced by the thermal saturation of the soil, which is influenced by the heat released from the air inside the pipe. Results showed that continuous operation for a duration of four days has minimal impact on the outlet air temperatures due to the implementation of night purging. Furthermore, the design and thermal efficiency of the EAHE are impacted by factors such as higher air velocity and reduced soil thermal conductivity.","PeriodicalId":479583,"journal":{"name":"Annals of West Univesity of Timişoara","volume":"119 34","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135137211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Corrosion Resistance of NiS, ZnS and NiS/ZnS Thin Films Deposited by Spray Pyrolysis Technique on Low Carbon Steel in 3.5%Nacl Solution 喷雾热解技术在低碳钢上沉积NiS、ZnS及NiS/ZnS薄膜在3.5%Nacl溶液中的耐蚀性

Annals of West Univesity of Timişoara Pub Date : 2023-11-10 DOI: 10.2478/awutp-2023-0009

Kamel Djail, Said Benramache

引用次数: 0

Structural and Optoelectronic Properties of Cubic Perovskite Type XAlO₃ (X = Gd and Dy) Theoretical Investigation 立方钙钛矿型XAlO3 (X = Gd和Dy)结构与光电性能的理论研究

Annals of West Univesity of Timişoara Pub Date : 2023-11-10 DOI: 10.2478/awutp-2023-0011

Bouhenna Abdelkder, Benyahia Karima, Beloufa Nabil, Boualem Kada, Bekheira Samir

{"title":"Structural and Optoelectronic Properties of Cubic Perovskite Type XAlO3 (X = Gd and Dy) Theoretical Investigation","authors":"Bouhenna Abdelkder, Benyahia Karima, Beloufa Nabil, Boualem Kada, Bekheira Samir","doi":"10.2478/awutp-2023-0011","DOIUrl":"https://doi.org/10.2478/awutp-2023-0011","url":null,"abstract":"Abstract In this paper, we have performed a theoretical study using the linear augmented and linearized plane wave method (FP-LAPW) implemented in the Wien2k computational code based on density functional theory (DFT) to determine the structural, electronic and optical properties of GdAlO 3 and DyAlO 3 perovskites. The exchange and correlation potential are treated by the generalized gradient approximation of Perdew-Burke-Ernzerhof (GGA-PBE) and modified Becke-Johnson potential (mBJ). The structural properties such as lattice parameter, modulus of compressibility and its derivative are in good agreement with other theoretical results. The electronic properties, such as band structure and density of state revealed an indirect energy gap in the L - xG direction for GdAlO 3 , with gap values of 2.879 eV (GGA-PBE), 5.006 eV (mBJ) in spin-up and 2.286 eV (mBJ), 2.736 eV (mBJ) in spin-dn.for DyAlO 3 perovskite, due to the over lap of the valence and conduction bands at Fermi level, which behaves like a metal oxide. We have also calculated the optical properties of these two compounds, such as dielectric function, refractive index, absorption coefficient and optical conductivity. They indicate that GdAlO 3 and DyAlO 3 perovskites could be useful for applications in UV photo catalysis.","PeriodicalId":479583,"journal":{"name":"Annals of West Univesity of Timişoara","volume":"16 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135137019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Structural and Thermodynamic Properties of Cu₂ZnSnS₄ Material: Theoretical Prediction Cu2ZnSnS4材料的结构和热力学性质:理论预测

Annals of West Univesity of Timişoara Pub Date : 2023-11-10 DOI: 10.2478/awutp-2023-0012

L. Boutahar, A. Benamrani, Z. Rouabah, S. Daoud

{"title":"Structural and Thermodynamic Properties of Cu2ZnSnS4 Material: Theoretical Prediction","authors":"L. Boutahar, A. Benamrani, Z. Rouabah, S. Daoud","doi":"10.2478/awutp-2023-0012","DOIUrl":"https://doi.org/10.2478/awutp-2023-0012","url":null,"abstract":"Abstract The present work aims to investigate the structural and thermodynamic properties of homogenous tetragonal Cu 2 ZnSnS 4 (CZTS) absorber material in Kesterite phase using first-principle calculations based on density functional theory (DFT). This approach requires only knowledge of the atomic species and crystal structure to predict several physical properties of materials. The Quantum Espresso code within the Ultra Soft pseudopotentials (USPP) and the local density approximation (LDA) were used in the calculations. Equilibrium unit cell volumes, bulk modulus, as well as the pressure derivative of the bulk modulus are predicted. In addition, several thermodynamic properties, especially: the Debye’s vibrational energy, the vibrational free energy, the vibrational entropy, and the constant volume heat capacity at different temperatures T of Cu 2 ZnSnS 4 material are calculated and discussed. Our study shows that the vibrational energy, the entropy and the constant volume heat capacity increase with increasing temperature, while the vibrational free energy decreases monotonously with the increase of temperature.","PeriodicalId":479583,"journal":{"name":"Annals of West Univesity of Timişoara","volume":"3 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135141610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chlorine Decay Simulation in Real Water Distribution System Using EPANET Program 用EPANET程序模拟真实配水系统中的氯衰变

Annals of West Univesity of Timişoara Pub Date : 2023-09-13 DOI: 10.2478/awutp-2023-0007

Mekki Malika, Bouabdesselam Hassiba, Laib Radouane, Beloufa Nabil, Bekheira Samir, Mohamed Trari

{"title":"Chlorine Decay Simulation in Real Water Distribution System Using EPANET Program","authors":"Mekki Malika, Bouabdesselam Hassiba, Laib Radouane, Beloufa Nabil, Bekheira Samir, Mohamed Trari","doi":"10.2478/awutp-2023-0007","DOIUrl":"https://doi.org/10.2478/awutp-2023-0007","url":null,"abstract":"Abstract Deterioration of treated drinking water intended for consumption during distribution may be due to physical, chemical or microbiological changes that occur in the water. In addition, the type of pipe material and disintegration of a disinfectant agent can affect the quality of the water supplied. Therefore, the research approach is to simulate the decay residual Cl 2 through potable water distribution networks produced by a desalination plant of Oran city in western Algeria. EPANET 2.0 software was used for estimating and predicting Cl 2 concentration at different water network points. The value of bulk flow decay coefficient (Kb) is set to -1,99 day -1 for a 50-year-old steel pipe, value for the wall decay coefficient (Kw) was determined using a trial-and-error procedure and assumed to be -1,2 day -1 . An efficient model with an extended simulations period of 72 h can plot spatial and temporal variations of residual Cl 2 concentrations at all links and nodes. Cl 2 is injected at the El Mactaa desalination plant, with a concentration of 0.6 mg/l permanently. As well, it was observed that 51.33% of the Cl 2 loss is due to pipe wall reaction, while 42.34 and 6.33% represent the bulk and tank reactions respectively. The results show that the range of residual Cl 2 (0.11-0,45 mg/l) and most of the measured values are less than are below the minimum authorized threshold (0.2 – 0.5 mg/l) WHO standard. Therefore, it is recommended to rehabilitate the old water transfer pipes and re-chlorination stations were necessary to add into network. Statistical analysis shows that the calculated results correspond well to the observed data. EPANET can follow the Cl 2 concentration in the drinking water network produced by El Mactaa desalination plant. It is a research tool to improve our understanding of water movement in the distribution system.","PeriodicalId":479583,"journal":{"name":"Annals of West Univesity of Timişoara","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135734858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0