INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS最新文献

Mathematical modelling of moisture sorption isotherms ofsome fruits 某些水果吸湿等温线的数学模拟

INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS Pub Date : 2022-07-01 DOI: 10.51558/2831-0527.2022.1.1.74

V. Mitrevski, Cvetanka Mitrevska

引用次数: 0

Energy Efficiency of the Novel Adaptive In-Line Process ElectricHeaters 新型自适应在线过程电加热器的能源效率

INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS Pub Date : 2022-07-01 DOI: 10.51558/2831-0527.2022.1.1.2

Fikret Alic

引用次数: 0

Thermo-hydraulic Performance Analysis of Al2O3/waterNanofluid Flow in a Tube Extended by Twisted Tape Al2O3/水纳米流体在扭带延伸管内流动的热-水力性能分析

INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS Pub Date : 2022-07-01 DOI: 10.51558/2831-0527.2022.1.1.34

Emrehan Gürsoy, Ezgi Çalar, A. Dağdeviren, Hayati Kadir Pazarlıoğlu, E. Gedik, K. Arslan

{"title":"Thermo-hydraulic Performance Analysis of Al2O3/water\u0000Nanofluid Flow in a Tube Extended by Twisted Tape","authors":"Emrehan Gürsoy, Ezgi Çalar, A. Dağdeviren, Hayati Kadir Pazarlıoğlu, E. Gedik, K. Arslan","doi":"10.51558/2831-0527.2022.1.1.34","DOIUrl":"https://doi.org/10.51558/2831-0527.2022.1.1.34","url":null,"abstract":"In this numerical study, heat transfer characteristics and hydrodynamical\u0000analysis have been performed for a circular tube inserted with twisted tape,\u0000which has different twisted pitch ratios (TPR=0, 50, 100, and 200). As a\u0000working fluid Al2O3/water nanofluid is used which has different volumetric\u0000concentrations (0.0≤φ≤3.0 vol. %). The numerical analysis has been carried out\u0000under the constant wall heat flux (q′′) of 4357 W/m2 for laminar flow ranging\u0000the Reynolds (Re) number from 1000 to 2000. According to numerical results,\u0000the highest average Nusselt number (Nu) and average Darcy friction factor (ff)\u0000have realized in twisted pitch ratio (TPR) 50. The reason is that when the\u0000twisted pitch ratio gradually decreases, stronger secondary flows and a higher\u0000velocity can be obtained. When compared with water, the highest Nu for\u0000TPR=50 has been obtained at φ=3.0 vol. % concentration as 61.15%. Also,\u0000when compared with TPR=0, the highest thermal performance enhancement\u0000(TPE) was realized at φ=3.0 vol. % concentration and Re=2000 conditions as\u000061.15% for TPR=50.\u0000\u0000Keywords:\u0000CFD\u0000Convective heat transfer\u0000Laminar flow\u0000Al2O3/water\u0000Twisted tape","PeriodicalId":196631,"journal":{"name":"INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123186897","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: 2

Experimental and Artificial Neural Network Investigation onthe Thermal Efficiency of Two-Phase Closed Thermosyphon 两相闭式热虹吸管热效率的实验与人工神经网络研究

INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS Pub Date : 2022-07-01 DOI: 10.51558/2831-0527.2022.1.1.19

E. Gedik, H. Kurt, Murat Pala, Abdullah Alakour, M. Kaya

{"title":"Experimental and Artificial Neural Network Investigation on\u0000the Thermal Efficiency of Two-Phase Closed Thermosyphon","authors":"E. Gedik, H. Kurt, Murat Pala, Abdullah Alakour, M. Kaya","doi":"10.51558/2831-0527.2022.1.1.19","DOIUrl":"https://doi.org/10.51558/2831-0527.2022.1.1.19","url":null,"abstract":"The main purpose of this study is to investigate the thermal efficiency of a\u0000Two-Phase Closed Thermosyphon (TPCT). For this purpose, initially, an\u0000experimental study was performed, then to predict the other experimental\u0000conditions ANN model which has used a wide range of thermal engineering\u0000systems was developed. A vertical copper pipe charged with different working\u0000fluids as pure water, ethanol, and ethylene glycol were used for TPCT. Impact\u0000of the various parameter such as heating power input, inclination angle, cooling\u0000water flow rate and working fluid type on the TPCT efficiency are examined. It\u0000is found that the increase in the inclination angle increased the TPCT efficiency\u0000while the increase in heating power input decreased efficiency. Regression\u0000analysis was applied to examine the performance of ANN between estimated\u0000and experimental data. The Mean Absolute Percentage Error (MAPE) was\u0000found to be less than 1.3 % for the training set and 3.1% for the test data set.\u0000The ANN predictions yield R2 in the range of 0.9998 for the training set and\u00000.9989 for the test data set. The obtained results from the experimental study\u0000and ANN were found in good agreement, and it is also concluded that from the\u0000study the ANN is a useful tool to estimate such thermal engineering problems.\u0000\u0000Keywords:\u0000Thermal efficiency\u0000Heat pipe\u0000Two-phase closed\u0000thermosyphon\u0000ANN","PeriodicalId":196631,"journal":{"name":"INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131303965","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: 1

Importance of nanofluid evaluations at identical velocity andpumping power: a specific evaluation for Ag-MgO/waterhybrid nanofluid flow through a pipe under turbulent regime 相同速度和泵送功率下纳米流体评估的重要性:湍流状态下Ag-MgO/水混合纳米流体流过管道的具体评估

INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS Pub Date : 2022-07-01 DOI: 10.51558/2831-0527.2022.1.1.48

Huseyin Kaya, Volkan Akgul, C. Uysal

{"title":"Importance of nanofluid evaluations at identical velocity and\u0000pumping power: a specific evaluation for Ag-MgO/water\u0000hybrid nanofluid flow through a pipe under turbulent regime","authors":"Huseyin Kaya, Volkan Akgul, C. Uysal","doi":"10.51558/2831-0527.2022.1.1.48","DOIUrl":"https://doi.org/10.51558/2831-0527.2022.1.1.48","url":null,"abstract":"In this study, heat transfer and fluid flow characteristics of Ag-MgO/water\u0000hybrid nanofluid flow through a pipe were numerically investigated under\u0000turbulent regime at identical Reynolds number, velocity and pumping power.\u0000To model the flow, the standard k turbulence model was used. In the analyses, Reynolds number was in the range from Re=10000 to Re=100000 and velocity ranged from V=0.3 m/s to V=3.0 m/s. As a result, it was found that the enhancements in convective heat transfer coefficient were obtained to be 23.72% for identical Reynolds number, 6.27% for identical velocity and 0.44% for identical pumping power. Nanofluids had higher velocities compared to their base fluid to be able to compare them at identical Reynolds\u0000number. It was found that this velocity differences can already cause a\u0000convective heat transfer enhancement of 16.29% without nanoparticle\u0000addition. Nanofluids have higher performance evaluation criteria than unity at identical Reynolds number while they have lower values than unity at identical velocity and pumping power. It can be concluded that the results obtained for identical Reynolds number are extremely optimistic and not realistic.\u0000Nanofluids should be examined at identical velocity or pumping power for a fair comparison.\u0000\u0000Keywords:\u0000Entropy generation\u0000Heat convection\u0000Heat transfer enhancement\u0000Nanofluid\u0000Turbulence","PeriodicalId":196631,"journal":{"name":"INTERNATIONAL JOURNAL OF THERMAL-FLUID ENGINEERING AND MODERN ENERGETICS","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125894955","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