Thermal Science最新文献_第6页

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

Suitability evaluation of urban human settlements based on fuzzy clustering analysis a case study of Hebei Province 基于模糊聚类分析的城市人居环境适宜性评价——以河北省为例

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2303009y

Zi-Xing Yuan, Xiaohua Yang, Yuqi Li

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

Numerical simulation of the gas flow through the rectangular channel with perforated plate 穿孔板矩形通道内气体流动的数值模拟

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci220426089m

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

{"title":"Numerical simulation of the gas flow through the rectangular channel with perforated plate","authors":"Z. Marković, M. Eric, R. Jovanović, I. Lazović","doi":"10.2298/tsci220426089m","DOIUrl":"https://doi.org/10.2298/tsci220426089m","url":null,"abstract":"The perforated plates are commonly used for gas flow control in the wide-angle diffusers of electrostatic precipitators of large power plants. Many studies dealt with the investigation of the effects of the perforated plate?s geometry on flow parameters in the cases where incoming flow is perpendicular to the plate and the plate is covering the whole cross-section of the flowing channel. These results are partially applicable in cases where flow is inclined on the plate or when the plate is not occupying the whole cross-section of the channel. The subject of this work is a numerical investigation of flow through the rectangular channel with a perforated plate in various positions in the cross-section of the channel. The aim was to investigate the effect of the plate position on the flow. The perforated plates were modeled as thin porous media of finite thickness by using the directional loss model. Numerical experiments are carried out by using Computational Fluid Dynamics software Ansys CFX. Results of pressure drop and velocity distribution behind the plate are compared to the results of CFD simulation of the full 3D plate model. In order to obtain a reasonable agreement both of the pressure drop and velocity distribution behind the plate when using a simplified thin porous plate model, the value of streamwise permeability of the plate had to be adjusted. The level of adjustments has determined iteratively and it depends on the plate position in the channel?s cross-section.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68242276","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

Numerical investigation of thermal hydraulic performance of a automobile heat transfer tube with ellipsoid dimples 带有椭球凹窝的汽车换热管热工性能数值研究

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci230313134z

Xiang Zhang, Ying Huang, Jing Zeng, Zong-xiong Ma, Jian-fei Song, Lunjun Chen, Tong Gao

{"title":"Numerical investigation of thermal hydraulic performance of a automobile heat transfer tube with ellipsoid dimples","authors":"Xiang Zhang, Ying Huang, Jing Zeng, Zong-xiong Ma, Jian-fei Song, Lunjun Chen, Tong Gao","doi":"10.2298/tsci230313134z","DOIUrl":"https://doi.org/10.2298/tsci230313134z","url":null,"abstract":"The heat transfer tube is one of the key components affecting the heat transfer performance of automobile radiators. Proposes a new kind of heat transfer tube with ellipsoidal dimples based on the elliptical heat transfer tube. The effects of the arrangement and pitch ellipsoidal dimples on the turbulent heat transfer and flow resistance of the heat transfer tube are further studied by numerical simulation in the range of Reynolds number in 4080~24480. The results show that the ellipsoid dimple arrangement makes the near-wall fluid produce different flow forms, which enhances the turbulence degree of the tube fluid and thus improves the convective heat transfer capacity of the tube. Among them: vertical parallel arrangement (Case1) causes convergent flow, oblique parallel arrangement (Case2) causes helical flow, and diagonal symmetrical arrangement (Case3) causes cross-helical flow. The cross-helical flow causes the most significant degree of turbulence, followed by the helical flow. Furthermore, the arrangement and pitch of the ellipsoidal dimples also have an essential influence on the heat transfer performance and flow resistance of the heat transfer tube. The Nusselt number and Friction factor of Case1, Case2 and Case3 increase successively. But the Nusselt number and Friction factor gradually decrease with the rise of the pitch of ellipsoidal dimples. However, under different ellipsoidal dimples pitch, the comprehensive performance of Case1, Case2 and Case3 is better than that of smooth elliptical tubes. Among them, Case3 has the best performance when P=15mm, and the performance evaluation criteria value is up to 1.39.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68262000","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

Application modelling of intelligent diagnosis for thermal cycle system 热循环系统智能诊断的应用建模

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2302101l

C. Liang

{"title":"Application modelling of intelligent diagnosis for thermal cycle system","authors":"C. Liang","doi":"10.2298/tsci2302101l","DOIUrl":"https://doi.org/10.2298/tsci2302101l","url":null,"abstract":"In order to solve the problem of intelligent fault diagnosis of thermal system of thermal power unit, the application modelling of intelligent diagnosis of thermal cycle system is proposed. This paper first filters the influence of the change of valve opening of steam turbine on the performance index under the condition of constant power, and qualitatively analyzes the actual change of the performance index compared with the reference working condition when the component fails, so as to eliminate the mutual influence between the components. Then, the selection principle of thermodynamic parameters is determined, the irreversible loss in the structural theory of thermal economics is introduced as the performance index, and the model is used to quantitatively calculate the change of performance index of each component under fault conditions to diagnose the failed component. Finally, APROS simulation software is used to simulate various fault conditions of 330 MW units in a power plant. The experimental results show that the recognition accuracy of the monitoring system designed in this paper can reach 98.33%. In conclusion, the method in this paper proves the feasibility of intelligent fault diag?nosis of thermodynamic system network.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68259271","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

Signal processing and thermal performance analysis of motor heat recovery system 电机热回收系统的信号处理及热性能分析

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2302125l

Jinwen Li

{"title":"Signal processing and thermal performance analysis of motor heat recovery system","authors":"Jinwen Li","doi":"10.2298/tsci2302125l","DOIUrl":"https://doi.org/10.2298/tsci2302125l","url":null,"abstract":"In order to realize the condition monitoring of the motor ?anytime, anywhere?, improve the detection accuracy and shorten the detection time, the author proposes a fault signal processing and diagnosis system for the motor heat recovery system based on the IoT. That is, based on the IoT technology, a mobile terminal oriented motor remote monitoring and fault diagnosis system, the sensing layer of the system collects real-time motor operation status data, and the transmission layer realizes data transmission, cloud storage and response to data requests from the application layer, finally, at the mobile end, the motor running status and diagnosis results are displayed through charts and text, so as to realize remote monitoring and fault diagnosis of the motor. The experimental results show that the accuracy of fault diagnosis test of GA-SVM in mobile terminal is more than 90%, and the running time is less than 30 ms, and the running time is very short. It proves that the mobile terminal uses the fault detection method based on GA-SVM model with high accuracy and short detection time, that is, the fault signal processing and diagnosis accuracy of the motor heat recovery system of the IoT is high and the detection time is short.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68259686","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

An efficient boundary meshfree computational approach for 3D multi-domain transient thermal analysis with variable thermal sources in nonhomogeneous media 非均匀介质中变热源三维多域瞬态热分析的有效边界无网格计算方法

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci230215099l

Jing Ling, Dong-Sheng Yang, Hong-Ying Wang, Hong-Zhong Mou

{"title":"An efficient boundary meshfree computational approach for 3D multi-domain transient thermal analysis with variable thermal sources in nonhomogeneous media","authors":"Jing Ling, Dong-Sheng Yang, Hong-Ying Wang, Hong-Zhong Mou","doi":"10.2298/tsci230215099l","DOIUrl":"https://doi.org/10.2298/tsci230215099l","url":null,"abstract":"Solutions of 3D multi-domain transient thermal analysis with variable thermal sources in nonhomogeneous media are separated into homogeneous and special solutions by an efficient boundary meshfree computational approach, namely virtual boundary meshfree Galerkin method. Homogeneous solutions are expressed by the virtual boundary element method. The virtual source functions of homogeneous solutions and the unknowable coefficients of special solutions can be formed by the radial basis function interpolation. Considering the control equation, the boundary and continuous conditions, and using the Galerkin method, the discrete formula for 3D multi-domain transient thermal analysis with variable thermal sources in nonhomogeneous media can be obtained. This discrete equation has symmetry. Meanwhile, in order to illustrate the steps of implementation more clearly, the final detailed implementation process is given. The numerical results of two calculation examples are obtained and compared to other methods and exact solutions. The proposed method's stability and exactness are validated for 3D multi-domain transient thermal analysis with variable thermal sources in nonhomogeneous media.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68259725","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

Application of thermal energy storage technology in power grid topology 储能技术在电网拓扑中的应用

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci2302199b

Xunge Bao, Qing Cai, Ji Zhang, Tianting Shang

引用次数: 0

Silica dopant effect on the performance of calcium carbonate/calcium oxide based thermal energy storage system 二氧化硅掺杂对碳酸钙/氧化钙基储能系统性能的影响

IF 1.7 4区工程技术

Thermal Science Pub Date : 2023-01-01 DOI: 10.2298/tsci230422165k

A. Khosa, Najam-ul-Hassan Shah, Xinyue Han, N. Husnain

{"title":"Silica dopant effect on the performance of calcium carbonate/calcium oxide based thermal energy storage system","authors":"A. Khosa, Najam-ul-Hassan Shah, Xinyue Han, N. Husnain","doi":"10.2298/tsci230422165k","DOIUrl":"https://doi.org/10.2298/tsci230422165k","url":null,"abstract":"CaCO3 is being studied for its application in thermal energy storage. However, it has drawbacks of slow reaction rate during calcination and incomplete reversible carbonation which limit its use. In this paper, SiO2 has been studied as a dopant for CaCO3 to improve its cyclic performance. CaCO3 samples were loaded with different concentrations of SiO2 and its effect on the thermal energy density of CaCO3 was determined. Afterwards, the effect of the dopant on the heat storage process of the synthesized composite along with kinetics of decarbonation reaction was investigated. Cyclic tests were performed to determine the reusability of the material. It was found that the addition of dopant helped to increase the rate of decarbonation reaction, thereby making the heat storage process more efficient as compared to pure CaCO3. The activation energy values are 255.9, 280.1, 244.9 and 234.8 kJ/mol for 5%, 15%, 30% and 0% doped SiO2 samples, respectively. Furthermore, thermal energy storage density increases when the amount of dopant decreases in the samples such as the 30% and 5% doped samples have gravimetric energy storage densities of 339.85 and 759.24 J/g, respectively. It was observed that the large quantities (15% and 30%) of dopant had introduced a new phase of Ca3SiO5 during CaCO3 decomposition.","PeriodicalId":23125,"journal":{"name":"Thermal Science","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68264147","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