Thermal Science最新文献_第10页

A new approach to fractional differential equations 分数阶微分方程的一种新方法

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci23s1301a

Hussam Alrabaiah, S. Hussain, Sami Awan, A. Zeb, K. Shah, T. Abdeljawad

引用次数: 0

Defect detection of GFRP laminates by barker codedmodulation excitation infrared thermal imaging 基于巴克码调制激发红外热成像的GFRP层压板缺陷检测

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci220807002t

Q. Tang, Ling Ran, Ze-Shen Qu, Chi-Wu Bub

引用次数: 0

Optimization of the flue gas flow controlling devices of the electrostatic precipitator of unit 4 in TPP "Nikola Tesla" TPP“尼古拉特斯拉”4号机组静电除尘器烟气流量控制装置的优化

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci220903024m

Z. Marković, M. Eric, P. Stefanovic, R. Jovanović, I. Lazović

{"title":"Optimization of the flue gas flow controlling devices of the electrostatic precipitator of unit 4 in TPP \"Nikola Tesla\"","authors":"Z. Marković, M. Eric, P. Stefanovic, R. Jovanović, I. Lazović","doi":"10.2298/tsci220903024m","DOIUrl":"https://doi.org/10.2298/tsci220903024m","url":null,"abstract":"Homogeneity of the flue gas flow through the chamber of an electrostatic precipitator is one of the basic influencing parameter on dedusting efficiency. This paper presents results of a multiobjective optimization study of the flue gas controlling devices of electrostatic precipitator of 324 MWe lignite fired unit A4 of Thermal Power Plant \"Nikola Tesla\" in Serbia. The aim was to achieve better flow homogeneity in the cross-section of the precipitator compared to the original design. Additional constraints were to maintain the minimum as possible overall weight of the proposed design as well as pressure drop through the precipitator. Numerical simulations based on Computational Fluid Dynamics were used to investigate dependence of the velocity distribution in the ducts and precipitator?s chamber with respect to the geometrical parameters of tested concepts of turning blades. A series of 22 detailed full-scale numerical models of the precipitator with different concepts of turning vanes designs were developed. Assessment of the flow field uniformity for each tested design was performed based on the analysis of several homogeneity parameters calculated for selected vertical cross-sections of the precipitator. After the reconstruction according to optimized design, results of measurements confirmed significant improvements of the velocity distribution in the vertical cross-sections of the precipitator, increase of dedusting efficiency and reduction of PM emission.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68246792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulation and modeling of a solar-aided underground energy storage system 太阳能辅助地下储能系统的仿真与建模

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci220913025s

Özdamar Sağlam, Seyit Özdamar, S. Mert

{"title":"Simulation and modeling of a solar-aided underground energy storage system","authors":"Özdamar Sağlam, Seyit Özdamar, S. Mert","doi":"10.2298/tsci220913025s","DOIUrl":"https://doi.org/10.2298/tsci220913025s","url":null,"abstract":"The significance of energy storage methods and related R&D studies are increasing due to the depletion of fossil fuels, rising energy prices, and growing environmental concerns. Storage of energy means elimination of practical concerns for the time difference between the time when the energy is produced and when it?s needed. The importance of producing and storing energy through renewable sources is increasing every day, especially in developing countries like T?rkiye, as such countries would like to reduce their dependence on foreign sources. This study focuses on an UTES (Underground Thermal Energy Storage) system that was modeled for Van Region, using M-file program. The performance of an isolated day heat system as a TES was investigated, and the thermal energy storage capacity of the system was researched for a 5x5x5 m soil area located on the Van Yuzuncu Yil University Campus. The temperature distribution, heat loss, and efficiency calculations were performed for a complete year and 3D representations of the findings were obtained. The lowest efficiencies were observed in May, while the highest efficiencies were observed in July. It was found that the maximum heat loss from the system took place during December and January, and the system could be easily and effectively become a heating source for a single household with the addition of a heat pump.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68248107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the simplified model of vertical double U-pipe ground heat exchanger 立式双u型管地下换热器简化模型研究

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci220922048w

Xin Wang, Qiang Fu, Changlong Wang

引用次数: 0

Experimental and numerical investigation of driving potential of biomass-pellet hot air generator for coupling with absorption heat pump 生物质颗粒热风发生器与吸收式热泵耦合驱动潜力的实验与数值研究

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221103068i

{"title":"Experimental and numerical investigation of driving potential of biomass-pellet hot air generator for coupling with absorption heat pump","authors":"","doi":"10.2298/tsci221103068i","DOIUrl":"https://doi.org/10.2298/tsci221103068i","url":null,"abstract":"This paper presents a numerical and experimental study of a heating system that consists of Hot Air Generator driven by biomass pellet burner to drive the NH3-H2O absorption heat pump made by Robur. The aim of this work is to fully test the system of Hot Air Generator for thermal potential, by developing a thermal field, while driving the absorption heat pump of medium capacities for residential purposes, and to make model of predicting the efficiencies of heating comparing to conveyed heat in desorber of absorption heat pump. Numerical simulations of the Hot Air Generator were performed in the commercial software Ansys Fluent and CFX. The experimental part was carried out in the laboratory of the Faculty of Mechanical Engineering in Nis, where the temperature and velocity measurements were obtained and compared to numerical results. Results were obtained for mass airflow through the Hot Air Generator and desorber of 0.17 and 0.2552 kg/s, pellet burner power of 15, 18, 21, 24, 27 and 30 kW, with air inlet temperature in desorber of around 89 to 140 ?C. and . The heating efficiency of the absorption heat pump goes from 1.01 to 1.37. The heat loss over the surfaces of Hot Air Generator goes from 0.6 to 0.9 kW depending on ambient air and surface temperatures. The system has the potential to be applied in low-temperature heating and the spare heat from combustion products and residual hot air can be used for different purposes.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68249713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nanofluids (CuO & TiO2) - water as heat transfer fluid in a TES system for applications of solar heating - an experimental study 纳米流体(CuO和TiO2) -水作为太阳能加热应用的TES系统中的传热流体-一项实验研究

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221215080k

Krishna Kondakrindi, M. Reddigari, Hemachandra Konireddy, U. Maheswari

{"title":"Nanofluids (CuO & TiO2) - water as heat transfer fluid in a TES system for applications of solar heating - an experimental study","authors":"Krishna Kondakrindi, M. Reddigari, Hemachandra Konireddy, U. Maheswari","doi":"10.2298/tsci221215080k","DOIUrl":"https://doi.org/10.2298/tsci221215080k","url":null,"abstract":"The present work aims to exploit the thermal performance of a packed bed of combined sensible & latent heat of storage unit with an integrated solar heat source. A cylindrical insulated storage tank in the Thermal Energy Storage (TES) unit is filled with spherical capsules separately which contains phase change material (PCM) as paraffin wax and stearic acid. The PCM usage has the benefits that it can be used as a thermal management tool and it reduces the cost and size of the system as it offers higher isothermal behavior and thermal storage capacity. The thermal conductivity of heat transfer fluid (HTF) can be enhanced by using nanoparticles mixed in water. Nanofluids are the more efficient fluids for the applications of heat-transfer. The water based nanofluids are used to transfer heat between the solar collector and storage tank which is a sensible heat storage material. The HTF materials are varied and Experimental trials have been conducted separately. Experimentation was carried out First by considering only water as HTF and is extended by adding water with one of the Nanomaterials- i.e.TiO2 and CuO, each in 3 HTF volume % as 0.2, 0.5 & 0.8. The variable source of heat supply considered is Solar flat plate collector. The study was transpired by varying the flow rates of nanofluids as 2.0, 4.0 and 6.0 l/min. The novelty of this work is to envisage the enhancement of heat transfer and to study the effects on the melting time of the PCMs of these fluids which were carried out. The performance parameters like charging time and system efficiency, instantaneous stored heat, cumulative stored heat were studied for the different HTFs and for the PCMs-paraffin and stearic acid. The batch wise process experiments for Discharging were carried out to recover the heat stored, and the results are presented.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68250721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Numerical simulation of O2/CO2 combustion in decomposition furnace 分解炉中O2/CO2燃烧的数值模拟

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221217073w

Bo Wang, H. Kao

{"title":"Numerical simulation of O2/CO2 combustion in decomposition furnace","authors":"Bo Wang, H. Kao","doi":"10.2298/tsci221217073w","DOIUrl":"https://doi.org/10.2298/tsci221217073w","url":null,"abstract":"The cement industry has become the second largest source of CO2 and NOx emissions after the power industry, it is imperative to reduce CO2 and NOx emissions. O2/CO2 combustion technology can achieve CO2 enrichment and NOx reduction. As a result, its application possibilities are bright. In this article, a TTF-type decomposition furnace serves as the research object for a CFD simulation. In addition, the effects of pulverized coal combined O2/N2 and pulverized coal mixed O2/CO2 combustion on the velocity field, temperature field, material component, and NOx concentration distribution in the furnace are investigated concerning the changes of kinetic parameters of CaCO3 decomposition under different working conditions. Compared with the O2/N2 atmosphere, the temperature distribution in the high-temperature zone of the decomposition furnace is more uniform under the O2/CO2 atmosphere. The temperature range is reduced in the area of extremely high temperatures. The NOx concentration at the decomposition furnace exit is reduced by 37%. The high concentration of CO2 at the output can be recycled and reused to reduce the greenhouse effect effectively. In addition, the high CO2 partial pressure increases the exit temperature by 111 K, doubles the O2 concentration, but decreases the raw meal decomposition rate from 95.9% to 82.2%. The process parameters must be improved to adapt to the O2/CO2 combustion technology.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68250786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A numerical scheme for Darcy-Forchheimer flow of non-Newtonian nanofluid under the effects of convective and zero mass flux boundary conditions 非牛顿纳米流体在对流和零质量通量边界条件下Darcy-Forchheimer流动的数值格式

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221230076a

M. Arif, W. Shatanawi, Y. Nawaz

引用次数: 0

Enhancing pool boiling heat transfer of modified surface by 3D Lattice Boltzmann method 三维晶格玻尔兹曼法增强改性表面池沸腾换热

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci230114121h

Qian Huang, Jing-zhi Zhou, Xiulan Huai, F. Zhou

引用次数: 0