Thermal Science最新文献_第6页

Process parameters optimization of water-waste derived biodiesel emulsion to permute as a sustainable and greener energy source 废水衍生生物柴油乳液的工艺参数优化，使其成为一种可持续的绿色能源

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci220909091g

Mahesh Gurusamy, Muralidharan Kandasamy, Suresh Vellaiyan

引用次数: 0

Three-dimensional problem of temperature and thermal flux distribution around defects with temperature-dependent material properties 具有温度相关材料性质缺陷的三维温度和热通量分布问题

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221003028z

Qianqian Zhang, Hao Song, Cunfa Gao

{"title":"Three-dimensional problem of temperature and thermal flux distribution around defects with temperature-dependent material properties","authors":"Qianqian Zhang, Hao Song, Cunfa Gao","doi":"10.2298/tsci221003028z","DOIUrl":"https://doi.org/10.2298/tsci221003028z","url":null,"abstract":"The analytical solution of three-dimensional heat conduction problem, including the temperature and thermal flux fields, is one of the important problems that have not been completely solved in solid mechanics. Considering the temperature dependence of material parameters makes the problem more difficult. In this paper, we first reduce the three-dimensional temperature-dependent heat conduction problem to the solution of three-dimensional Laplace equation by introducing the intermediate function. Then, the generalized ternary function is proposed, and the general solution of three-dimensional Laplace equation is given. Finally, the analytical solutions of three specific problems are obtained and the corresponding temperature-thermal flux fields are discussed. The results show that the thermal flux field of three-dimensional temperature dependent problem is the same as the classical constant thermal conductivity approach result, while the temperature field is different from the classical result. Thermal flux at a planar defect boundary has r-1/2 singularity, and its intensity is proportional to the fourth root of defect width. On the other hand, when blocked by a planar defect, the thermal flux distribution will re-adjusted so that it overflows at the same rate from all parts of the planar defect boundary.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":"10 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68248863","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

Experiment and simulation studies on thermal performance of a novel water-cooling premixed wall-hung gas boiler 新型水冷预混壁挂燃气锅炉热工性能的实验与仿真研究

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221017067w

Ning Wang, S. Deng, Zongyi Wang, Y. Gui, M. Le, Qinxin Zhao, Huaishuang Shao

{"title":"Experiment and simulation studies on thermal performance of a novel water-cooling premixed wall-hung gas boiler","authors":"Ning Wang, S. Deng, Zongyi Wang, Y. Gui, M. Le, Qinxin Zhao, Huaishuang Shao","doi":"10.2298/tsci221017067w","DOIUrl":"https://doi.org/10.2298/tsci221017067w","url":null,"abstract":"A wall-hung gas boiler was innovatively proposed and designed in this paper. Water-cooling premixed combustion and enhanced condensation heat exchange technology were adopted in the boiler. The extruded aluminum plate-fin structure was adopted in the burner and condensing heat exchanger. Experiment and numerical simulation studies were conducted on the flow, combustion, and heat exchange characteristics of the boiler. The effect of the fin structure, excess air coefficient, heat load, and water-cooling temperature on the thermal performance of the boiler was analyzed. The results showed that reliable ignition, stable combustion, uniform flame distribution, and low pollutant emissions can be achieved in the wall-hung gas boiler. Affected by burning intensity and internal flue gas recirculation, when the burner plate-fin gap was 1.63 mm, the flame was the shortest and the NOx emissions were the lowest. Under this fin condition, ultra-high efficiency and ultra-low emissions can be achieved in the boiler with a low excess air coefficient. When the excess air coefficient was 1.3, the NOx emissions were less than 30 mg/m3 at the heat load of 4-14 kW, and the thermal efficiency can reach up to 102.8% at the rated load of 14 kW. Within the scope of the experiment, the NOx emissions changed little with the water-cooling temperature. At the temperature of 333 K, there was still a great NOx emission reduction effect.","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":"68249088","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

Direct numerical simulation of double diffusive natural convection in a closed mixture cavity heated from below 从下加热的密闭混合腔内双扩散自然对流的直接数值模拟

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221107069x

Yaowen Xia, Juan Chen

引用次数: 0

Heat transfer enhancement in a helically coiled convergent and divergent tube heat exchanger with alumina oxide nanofluid 氧化氧化铝纳米流体对螺旋盘管换热器传热的增强作用

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci221205140s

Nandhakumar Shankar, Perumalsamy Sethusundaram Parambakkattur, M. Chandran

{"title":"Heat transfer enhancement in a helically coiled convergent and divergent tube heat exchanger with alumina oxide nanofluid","authors":"Nandhakumar Shankar, Perumalsamy Sethusundaram Parambakkattur, M. Chandran","doi":"10.2298/tsci221205140s","DOIUrl":"https://doi.org/10.2298/tsci221205140s","url":null,"abstract":"In this investigation, the analysis of the heat transfer coefficient of a shell, helically coiled convergent-divergent tube heat exchanger has been carried out by utilizing Al2O3/water nanofluid. The nanofluid was prepared using a two-stage technique with proportions of 0.1vol%, 0.3vol%, and 0.5vol%. The inner heat transfer coefficient, overall heat transfer coefficient, and Nusselt number were analyzed and it found that the heat transfer coefficient is increased, with increase of inner dean number and particle volume concentration. The experimental tests were carried out in the range of 1100<De<4200. When compared to base fluid, the overall heat transfer coefficient improved by 27%, 55%, and 78% at 0.1%, 0.3% and 0.5% with Al2O3/water Nanofluid respectively. When compared to base fluid at a fixed dean number, the increase in Nusselt number was viewed as 27%, 51%, and 72% at 0.1%, 0.3%, and 0.5% of Al2O3/water nanofluid, respectively. The investigations of enhancement were increased due to increased nanofluid thermal conductivity while increasing the %vol concentration and Brownian movement of the nanoparticles. The viscosity of nanofluid is increased with increase of particle volume which increase the pressure drop. It is concluded the convergent-divergent helically coiled tube heat exchangers along with nanofluid is able to enhance the heat transfer with considerable pressure drop. There is no adverse effect on the development of optional streams or the blending of liquids.","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":"68250589","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

Investigation of thermal and dimensional behavior of 3-D printed materials using thermal imaging and 3-D scanning 利用热成像和三维扫描技术研究三维打印材料的热行为和尺寸行为

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2301021g

Z. Golubovic, M. Travica, Isaak Trajković, A. Petrovic, Ž. Mišković, N. Mitrović

{"title":"Investigation of thermal and dimensional behavior of 3-D printed materials using thermal imaging and 3-D scanning","authors":"Z. Golubovic, M. Travica, Isaak Trajković, A. Petrovic, Ž. Mišković, N. Mitrović","doi":"10.2298/tsci2301021g","DOIUrl":"https://doi.org/10.2298/tsci2301021g","url":null,"abstract":"Fused deposition modeling is one of the most widely used 3-D printing technologies, among other additive manufacturing processes, because it is easy to use, can produce parts faster, and the cost of the finished part is low. Printing processes and finished parts are often studied and characterized using different techniques to collect mechanical, numerical, thermal and dimensional data, with the aim of improving and optimizing the result. The first part of this research is based on the observation of temperature changes with a thermal imaging camera during the fused deposition modeling printing process and during the cooling process after printing. Specimens of polylactic acid and polylactic acid-X improved with second-phase particles were prepared to compare the thermal and dimensional properties of the two materials. The obtained results determined the characteristic temperature behavior of the materials. In the second part of the research, a 3-D optical scanner was used to verify the stability and accuracy of the printed specimens over time. The proposed measurement period showed that stabilization of the parameters takes place, and further follow-up should be performed thereafter.","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":"68255911","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

Possibilities of steam boiler process optimization in the TPP Ugljevik TPP中蒸汽锅炉工艺优化的可能性

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2301133s

Goran Stupar, D. Tucaković, Ognjen Stamenković, Luka Petrovic, Borivoje Vujicic, Zarko Novakovic, Željko Milanović

{"title":"Possibilities of steam boiler process optimization in the TPP Ugljevik","authors":"Goran Stupar, D. Tucaković, Ognjen Stamenković, Luka Petrovic, Borivoje Vujicic, Zarko Novakovic, Željko Milanović","doi":"10.2298/tsci2301133s","DOIUrl":"https://doi.org/10.2298/tsci2301133s","url":null,"abstract":"The paper presents a technical solution for modernization with the aim of increasing the efficiency of the steam boiler of TPP Ugljevik, which implies the reorganization of the combustion system. More efficient operation of the furnace can be achieved by replacing the existing burners, reducing the number of burner levels as well as the organization of tangential combustion. The flame formed in the shape of a tube around the two central combustion vortices provides a larger amount of heat transferred to the combustion furnace, less fouling of its screen walls and thus a lower average temperature of the combustion products at its outlet. As the chosen reorganization affects the increase of the temperature of the superheated steam and the decrease of the temperature of the reheated steam, it has been proposed to reduce the area of the semi-irradiated superheater and increase the area of the second reheater. Taking into consideration that the reorganization of the combustion system may lead to the change of the thermal load of the evaporator located in the furnace, the paper presents the work of the steam boiler operation under new operating conditions. Used calculation system enables reliable prediction of operating characteristics of the steam boiler in new operating conditions of combustion, and its application helps assess the quality of the boiler in terms of how effective, efficient, safe and environmentally friendly its operating mode is. In this way, it is possible to form a comprehensive description of the operating mode of the steam boiler.","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":"68256405","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 new combined ZK-mZK dynamic model for Rossby solitary wave Rossby孤立波的一种新的联合ZK-mZK动力学模型

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2301599z

Baojun Zhao, Zi-Ming Jiang, Wen-Jin Sun

引用次数: 0

Discrete element analysis on the influence of drilling fluid pressure on core discing in pressure-preserved coring 保压取心中钻井液压力对岩心切割影响的离散元分析

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2301655w

Ding-Ming Wang, Ling Chen, D. Guo, Zhi-qiang Liu, Ju Li, Xun Yang, Yi-Wei Zhang

引用次数: 0

Analysis of propagation characteristics of hydrogen flame in shock tube in integrated energy system 综合能源系统中氢火焰激波管内传播特性分析

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2302059z

B. Zhao

{"title":"Analysis of propagation characteristics of hydrogen flame in shock tube in integrated energy system","authors":"B. Zhao","doi":"10.2298/tsci2302059z","DOIUrl":"https://doi.org/10.2298/tsci2302059z","url":null,"abstract":"In order to study the explosion law of hydrogen and air premixed gas in the pipe-line, the author proposes an analysis of the propagation characteristics of hydrogen in the shock tube in the integrated energy system. Use a square transparent pipe with a size of 150 mm?150 mm?1000 mm, the shape of the explosion flame, the propagation velocity and the pressure change with the hydrogen volume fraction from 10-40% were observed through experiments. Flame spread and pressure were recorded and measured by high speed cameras and pressure sensors, respectively. Experimental results show that the explosion flame characteristics and pressure changes are greatly affected by the hydrogen volume fraction. With the increase of hydrogen volume fraction, the maximum velocity and maximum value of flame in pipe increase significantly. The maximum flame propagation speed is increased from 18.3-304.2 m/s, and the propagation time is shortened from 123.5-10.5 ms. The pressure peak increased from 2.95-34.06 kPa. The analysis of the propagating characteristics of the hydrogen flame in the shock tube in the integrated energy system can well reflect the intensity of the hydrogen explosion. Do not use abbreviations and acronyms in the abstract.","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":"68258769","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