<div><div>Improving heat transfer in thermal systems is critical to achieving better results in a variety of systems. The study aims to investigate the laminar flow dynamics of Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>-SiO<sub>2</sub>-TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/water hybrid nanofluids, emphasizing how the channel geometry affects the velocity, temperature distribution, and heat transfer efficiency. This understanding is crucial for optimizing industrial processes, such as cooling systems and heat exchangers. Effects of various nanoparticle shapes, joule heating, viscous dissipation, thermal radiation, and heat source/sink on the system’s behavior are evaluated. Governing partial differential equations are transformed into ordinary differential equations using similarity variables and are solved semi-analytically via the homotopy analysis method. As the Hartmann number increases from 1 to 7, the heat transfer rate rises from 0.02% to 0.9%. When the radiation parameter and Eckert number are varied from 0.05 to 0.2, the heat transfer rate increases significantly, from 1.2% to 4.86% and 3.43% to 13.73%, respectively. Heat transfer rate increased by 16.28% with heat source (<span><math><mrow><mi>Q</mi><mo>=</mo><mn>2</mn></mrow></math></span>) and decreased by -16.12% with heat sink (<span><math><mrow><mi>Q</mi><mo>=</mo><mo>−</mo><mn>2</mn></mrow></math></span>). Platelet-shaped nanoparticles demonstrate lower skin friction in divergent channels, whereas spherical nanoparticles exhibit higher skin friction; this trend reverses in convergent channels. Suspensions of nanoparticles with a 5% volume fraction achieve heat transfer rates of 1.88%, 4.07%, 10.54%, 19.20%, and 8.74% for spheres, bricks, cylinders, platelets, and blades, respectively. The study reveals that Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>/H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O, Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>-TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O, and Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>-SiO<sub>2</sub>-TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O nanofluids have the best heat transfer rates for mono nanofluid, hybrid nanofluid, and ternary hybrid nanofluid by 15.24%, 19.92%, and 19.20%, respectively. Finally, mul
{"title":"Thermal performance analysis of magnetohydrodynamic Al2O3-SiO2-TiO2/water ternary hybrid nanofluid in converging and diverging channels with nanoparticle shape effects","authors":"C.M. Mohana , B. Rushi Kumar , Sunitha Nagarathnam , I.S. Shivakumara","doi":"10.1016/j.csite.2024.105429","DOIUrl":"10.1016/j.csite.2024.105429","url":null,"abstract":"<div><div>Improving heat transfer in thermal systems is critical to achieving better results in a variety of systems. The study aims to investigate the laminar flow dynamics of Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>-SiO<sub>2</sub>-TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/water hybrid nanofluids, emphasizing how the channel geometry affects the velocity, temperature distribution, and heat transfer efficiency. This understanding is crucial for optimizing industrial processes, such as cooling systems and heat exchangers. Effects of various nanoparticle shapes, joule heating, viscous dissipation, thermal radiation, and heat source/sink on the system’s behavior are evaluated. Governing partial differential equations are transformed into ordinary differential equations using similarity variables and are solved semi-analytically via the homotopy analysis method. As the Hartmann number increases from 1 to 7, the heat transfer rate rises from 0.02% to 0.9%. When the radiation parameter and Eckert number are varied from 0.05 to 0.2, the heat transfer rate increases significantly, from 1.2% to 4.86% and 3.43% to 13.73%, respectively. Heat transfer rate increased by 16.28% with heat source (<span><math><mrow><mi>Q</mi><mo>=</mo><mn>2</mn></mrow></math></span>) and decreased by -16.12% with heat sink (<span><math><mrow><mi>Q</mi><mo>=</mo><mo>−</mo><mn>2</mn></mrow></math></span>). Platelet-shaped nanoparticles demonstrate lower skin friction in divergent channels, whereas spherical nanoparticles exhibit higher skin friction; this trend reverses in convergent channels. Suspensions of nanoparticles with a 5% volume fraction achieve heat transfer rates of 1.88%, 4.07%, 10.54%, 19.20%, and 8.74% for spheres, bricks, cylinders, platelets, and blades, respectively. The study reveals that Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>/H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O, Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>-TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O, and Al<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>-SiO<sub>2</sub>-TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O nanofluids have the best heat transfer rates for mono nanofluid, hybrid nanofluid, and ternary hybrid nanofluid by 15.24%, 19.92%, and 19.20%, respectively. Finally, mul","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105429"},"PeriodicalIF":6.4,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-10DOI: 10.1016/j.csite.2024.105479
Cheng Fu , Tianyue Guo , Yu Sui , Tingting Zhu , Bin Huang
To address liquid accumulation in horizontal gas wells, a specialized internal vortex tool (IVT) was developed for use in the horizontal sections, functioning as a drainage gas recovery device. This tool operates by leveraging centrifugal forces generated during fluid swirl to separate liquid from gas. The study examined the performance of IVT under various operational conditions and sought to identify optimal structural parameters. Through a controlled variable approach, the impact of inlet velocity and the water-gas volume ratio on pressure drop range, MGV (maximum gas velocity), and MVFLP (maximum liquid phase volume fraction) was analyzed. The results indicated that when the inlet velocity is between 2 and 4 m/s and the water to gas volume ratio is between 0.5 and 2m3/104 m3, the smaller the inlet velocity and the smaller the water to gas volume ratio, the better the gas-liquid separation effect of the IVT. An orthogonal test was subsequently employed to fine-tune the tool's structural parameters for different conditions, culminating in the creation of a comprehensive optimization chart for IVT. This study can effectively design drainage gas production tools for gas wells under different working conditions, reduce energy loss during drainage gas production, effectively utilize downhole resources, and achieve the goal of increasing natural gas well production and reducing costs.
{"title":"Working condition sensitivity analysis and optimal structure parameter determination of IVT based on CFD and orthogonal experiment","authors":"Cheng Fu , Tianyue Guo , Yu Sui , Tingting Zhu , Bin Huang","doi":"10.1016/j.csite.2024.105479","DOIUrl":"10.1016/j.csite.2024.105479","url":null,"abstract":"<div><div>To address liquid accumulation in horizontal gas wells, a specialized internal vortex tool (IVT) was developed for use in the horizontal sections, functioning as a drainage gas recovery device. This tool operates by leveraging centrifugal forces generated during fluid swirl to separate liquid from gas. The study examined the performance of IVT under various operational conditions and sought to identify optimal structural parameters. Through a controlled variable approach, the impact of inlet velocity and the water-gas volume ratio on pressure drop range, MGV (maximum gas velocity), and MVFLP (maximum liquid phase volume fraction) was analyzed. The results indicated that when the inlet velocity is between 2 and 4 m/s and the water to gas volume ratio is between 0.5 and 2m<sup>3</sup>/10<sup>4</sup> m<sup>3</sup>, the smaller the inlet velocity and the smaller the water to gas volume ratio, the better the gas-liquid separation effect of the IVT. An orthogonal test was subsequently employed to fine-tune the tool's structural parameters for different conditions, culminating in the creation of a comprehensive optimization chart for IVT. This study can effectively design drainage gas production tools for gas wells under different working conditions, reduce energy loss during drainage gas production, effectively utilize downhole resources, and achieve the goal of increasing natural gas well production and reducing costs.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105479"},"PeriodicalIF":6.4,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To reduce the operational energy consumption of a compressed air system coupled with a solar and air-source heat pump hot water system, a model was established using TRNSYS, and the Taguchi method was employed to design experiments for four factors influencing the system's energy consumption. The main effects and relevant statistical analyses of the experimental results revealed that the key factors influencing the system's energy consumption, in order of significance, are: solar collector area > heat pump unit capacity > thermal storage tank volume > solar collector installation angle. Compared to conventional full-factor orthogonal methods, the Taguchi approach reduced the number of orthogonal experiments while effectively predicting the optimal parameter combinations, thereby providing a more efficient, stable, and economical design solution for the coupled system. Based on the identified optimal parameter combinations, the system was optimized, resulting in an increase in the annual solar energy assurance rate from 19.52 % to 37.26 %. Furthermore, the annual operational energy consumption was reduced by 12.45 %, leading to an estimated annual cost savings of approximately 34,000 yuan. The findings of this study offer valuable reference for the design and optimization of multi-energy complementary hot water systems.
{"title":"Optimization study of a multi-heat source coupled bathing hot water system","authors":"Yunxin Huang, Jinghui Luo, Yongchang Zhou, Xiaoxuan Wu, Nianchen Wang, Shicheng Xin, Changjian Zhang","doi":"10.1016/j.csite.2024.105439","DOIUrl":"10.1016/j.csite.2024.105439","url":null,"abstract":"<div><div>To reduce the operational energy consumption of a compressed air system coupled with a solar and air-source heat pump hot water system, a model was established using TRNSYS, and the Taguchi method was employed to design experiments for four factors influencing the system's energy consumption. The main effects and relevant statistical analyses of the experimental results revealed that the key factors influencing the system's energy consumption, in order of significance, are: solar collector area > heat pump unit capacity > thermal storage tank volume > solar collector installation angle. Compared to conventional full-factor orthogonal methods, the Taguchi approach reduced the number of orthogonal experiments while effectively predicting the optimal parameter combinations, thereby providing a more efficient, stable, and economical design solution for the coupled system. Based on the identified optimal parameter combinations, the system was optimized, resulting in an increase in the annual solar energy assurance rate from 19.52 % to 37.26 %. Furthermore, the annual operational energy consumption was reduced by 12.45 %, leading to an estimated annual cost savings of approximately 34,000 yuan. The findings of this study offer valuable reference for the design and optimization of multi-energy complementary hot water systems.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105439"},"PeriodicalIF":6.4,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.csite.2024.105466
Zi-Xiang Tong
The field synergy principles for convective heat transfer and flow resistance are integrated in this study. A local three-field synergy angle of velocity, temperature and pressure fields is proposed to evaluate the local comprehensive performance of heat transfer and pumping power consumption. The angle is based on the polar angle of a plot with dot products of velocity and enthalpy/total pressure gradients, respectively, as coordinates. The polar angle is then shifted by the observation that the enhancement of heat transfer rate at the cost of pumping power decreases from the second quadrant to the forth quadrant. The application of the synergy angle is demonstrated by examples of flow and heat transfer in channels with different fin structures. Inspired by the distribution of the synergy angle, Airfoil-Rect fin and Rhom-Rect fin structures are designed, which can improve the heat transfer rate with constraints of pumping power consumption. The present study provides a possible approach for heat transfer enhancement.
{"title":"A local synergy angle of velocity, temperature and pressure fields for enhancement of comprehensive heat transfer performance","authors":"Zi-Xiang Tong","doi":"10.1016/j.csite.2024.105466","DOIUrl":"10.1016/j.csite.2024.105466","url":null,"abstract":"<div><div>The field synergy principles for convective heat transfer and flow resistance are integrated in this study. A local three-field synergy angle of velocity, temperature and pressure fields is proposed to evaluate the local comprehensive performance of heat transfer and pumping power consumption. The angle is based on the polar angle of a plot with dot products of velocity and enthalpy/total pressure gradients, respectively, as coordinates. The polar angle is then shifted by the observation that the enhancement of heat transfer rate at the cost of pumping power decreases from the second quadrant to the forth quadrant. The application of the synergy angle is demonstrated by examples of flow and heat transfer in channels with different fin structures. Inspired by the distribution of the synergy angle, Airfoil-Rect fin and Rhom-Rect fin structures are designed, which can improve the heat transfer rate with constraints of pumping power consumption. The present study provides a possible approach for heat transfer enhancement.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105466"},"PeriodicalIF":6.4,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.csite.2024.105443
Naim Ben Ali , Karrar A. Hammoodi , Saman Aminian , Aman Sharma , Dheyaa J. Jasim , Ali I. Hameed , Rifaqat Ali , Husam Rajab , Mohsen Ahmed , Pooya Pasha , Seyyed Hassan Hashemi
Given the growing significance of renewable energy systems, researchers systems focus on optimizing heat transfer mechanisms. This study delves into the performance characteristics of a Slinky geothermal heat exchanger employing water as the working fluid. This study investigates how the step parameter of twisted tape affects hydrothermal parameters in Slinky heat exchangers, as well as the ideal depth of installation in the ground for improved performance. The numerical analysis results show that the Slinky heat exchanger shows superior thermal efficiency when employing a 200 mm pitch strip compared to the other two modes tested. During the first stage, the thermal performance coefficient peaked at 1.93 with a mass flow rate of 0.5 kg/s. Reducing the turbulator pitch increased fluid interaction and enhanced rotation within a larger fluid volume. Consequently, this augments heat transfer and improves the heat exchanger's overall thermal efficiency. Therefore, Slinky exchangers present a viable substitute for other ground-based heat exchangers by effectively enhancing heat transfer without inducing excessive pressure drop.
{"title":"Analyzing heat transfer in a horizontal geothermal heat exchanger using numerical methods","authors":"Naim Ben Ali , Karrar A. Hammoodi , Saman Aminian , Aman Sharma , Dheyaa J. Jasim , Ali I. Hameed , Rifaqat Ali , Husam Rajab , Mohsen Ahmed , Pooya Pasha , Seyyed Hassan Hashemi","doi":"10.1016/j.csite.2024.105443","DOIUrl":"10.1016/j.csite.2024.105443","url":null,"abstract":"<div><div>Given the growing significance of renewable energy systems, researchers systems focus on optimizing heat transfer mechanisms. This study delves into the performance characteristics of a Slinky geothermal heat exchanger employing water as the working fluid. This study investigates how the step parameter of twisted tape affects hydrothermal parameters in Slinky heat exchangers, as well as the ideal depth of installation in the ground for improved performance. The numerical analysis results show that the Slinky heat exchanger shows superior thermal efficiency when employing a 200 mm pitch strip compared to the other two modes tested. During the first stage, the thermal performance coefficient peaked at 1.93 with a mass flow rate of 0.5 kg/s. Reducing the turbulator pitch increased fluid interaction and enhanced rotation within a larger fluid volume. Consequently, this augments heat transfer and improves the heat exchanger's overall thermal efficiency. Therefore, Slinky exchangers present a viable substitute for other ground-based heat exchangers by effectively enhancing heat transfer without inducing excessive pressure drop.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105443"},"PeriodicalIF":6.4,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142659980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.csite.2024.105467
Dingyi Wei , Weijie Cao , Cuifeng Du , Zhun Li , Fan Zhang , Junjie Guo
The application of backfill mining method in deep mines is becoming more and more common, but the accompanied hydration heat of cemented tailings backfill (CTB) exacerbates the thermal damage in the depths. This study establishes and validates the wind temperature prediction model of excavation roadway containing CTB heat sources according to the simulation results and field measurements. The results show that the hydration heat of CTB has an important influence on the wind temperature in excavation roadway, and the use of ventilation to alleviate it is effective. The wind temperature increases gradually with the distance between the measurement point and air duct. The overall mean absolute percentage error (MAPE) between the theoretical calculated values and the simulated values of the established wind temperature prediction model of excavation roadway containing CTB is 0.08 %, which verifies the accuracy and validity of the model. The wind temperature prediction model can be used to guide the development of appropriate ventilation and cooling programs at the site, providing a guarantee for personnel health and safe and efficient mine production.
{"title":"Wind temperature prediction model for ventilation cooling in excavation roadway containing cemented tailings backfill heat sources","authors":"Dingyi Wei , Weijie Cao , Cuifeng Du , Zhun Li , Fan Zhang , Junjie Guo","doi":"10.1016/j.csite.2024.105467","DOIUrl":"10.1016/j.csite.2024.105467","url":null,"abstract":"<div><div>The application of backfill mining method in deep mines is becoming more and more common, but the accompanied hydration heat of cemented tailings backfill (CTB) exacerbates the thermal damage in the depths. This study establishes and validates the wind temperature prediction model of excavation roadway containing CTB heat sources according to the simulation results and field measurements. The results show that the hydration heat of CTB has an important influence on the wind temperature in excavation roadway, and the use of ventilation to alleviate it is effective. The wind temperature increases gradually with the distance between the measurement point and air duct. The overall mean absolute percentage error (MAPE) between the theoretical calculated values and the simulated values of the established wind temperature prediction model of excavation roadway containing CTB is 0.08 %, which verifies the accuracy and validity of the model. The wind temperature prediction model can be used to guide the development of appropriate ventilation and cooling programs at the site, providing a guarantee for personnel health and safe and efficient mine production.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105467"},"PeriodicalIF":6.4,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.csite.2024.105472
Yinwei Wang, Saleem Jasim Abbas, Ramdevsinh Jhala, Ankur Kulshreshta, N. Beemkumar, Vikasdeep Singh Mann, Ibrahim Mahariq
This study focuses on enhancing the thermal efficiency of a double-tube heat exchanger used in cooling systems for large-scale internal combustion engines by incorporating a novel vibrating cylindrical turbulator. The experimental investigation examined inlet Reynolds numbers ranging from 1052 to 8430 and evaluated various turbulator configurations, including fixed close-ended, fixed open-ended, vibrating close-ended, and vibrating open-ended cylindrical turbulators. Additionally, the impact of turbulator length, varying from 10 to 30 cm, on thermal-frictional characteristics was analyzed. The optimal configuration was determined using the thermal enhancement factor (TEF). Results showed that close-ended cylindrical turbulators significantly outperformed the open-ended configurations in terms of heat transfer and TEF. Although the vibrating turbulator produced a higher pressure drop compared to the fixed turbulator, it achieved a much higher heat transfer rate and TEF, making it a viable option for heat exchangers. The study also found that increasing the turbulator length leads to increased heat transfer, TEF, and pressure drop. The maximum TEF was recorded with the vibrating close-ended cylindrical turbulator, where heat transfer and pressure drop were up to 385 % and 95 % greater than those of a plain tube heat exchanger, respectively, resulting in a perfect TEF value of 3.45.
{"title":"Thermal frictional analysis of a novel vibrating cylindrical turbulator in double tube heat exchangers for engine cooling","authors":"Yinwei Wang, Saleem Jasim Abbas, Ramdevsinh Jhala, Ankur Kulshreshta, N. Beemkumar, Vikasdeep Singh Mann, Ibrahim Mahariq","doi":"10.1016/j.csite.2024.105472","DOIUrl":"https://doi.org/10.1016/j.csite.2024.105472","url":null,"abstract":"This study focuses on enhancing the thermal efficiency of a double-tube heat exchanger used in cooling systems for large-scale internal combustion engines by incorporating a novel vibrating cylindrical turbulator. The experimental investigation examined inlet Reynolds numbers ranging from 1052 to 8430 and evaluated various turbulator configurations, including fixed close-ended, fixed open-ended, vibrating close-ended, and vibrating open-ended cylindrical turbulators. Additionally, the impact of turbulator length, varying from 10 to 30 cm, on thermal-frictional characteristics was analyzed. The optimal configuration was determined using the thermal enhancement factor (TEF). Results showed that close-ended cylindrical turbulators significantly outperformed the open-ended configurations in terms of heat transfer and TEF. Although the vibrating turbulator produced a higher pressure drop compared to the fixed turbulator, it achieved a much higher heat transfer rate and TEF, making it a viable option for heat exchangers. The study also found that increasing the turbulator length leads to increased heat transfer, TEF, and pressure drop. The maximum TEF was recorded with the vibrating close-ended cylindrical turbulator, where heat transfer and pressure drop were up to 385 % and 95 % greater than those of a plain tube heat exchanger, respectively, resulting in a perfect TEF value of 3.45.","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"2 1","pages":""},"PeriodicalIF":6.8,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.csite.2024.105428
Ali Haider , M.S. Anwar , Yufeng Nie , Fahad Saleh Almubaddel , Magda Abd El-Rahman
Purpose:
This study investigates the effects of hybrid nanoparticles on thermal performance, focusing on convection, magnetic fields, diffusion, radiation, and chemical reactions in porous media. An -based fractional Carreau hybrid nanofluid is utilized to enhance heat transfer for industrial applications like gas turbines and condensers.
Design/Methodology/Approach:
The Caputo definition of fractional derivatives models the fluid flow, integrating integer and non-integer dynamics. The governing equations are dimensionally reduced and solved using the explicit finite difference method (EFD), with stability and convergence criteria ensuring accuracy. Key parameters, including the Sherwood and Nusselt numbers, are examined to understand thermal and mass transfer behavior.
Findings:
Results show that fractional exponents and thermophysical properties significantly influence flow behavior. Fluid velocity increases with the fractional exponent due to reduced resistance, while higher porosity parameter decreases velocity. The temperature gradient decreases by 20.31% with the fractional exponent and by 22.87% with the Weissenberg number. Skin friction increases by 28.17% with the magnetic parameter, and higher thermal conductivity enhances temperature profiles.
{"title":"Optimizing heat and mass transfer in Carreau nanofluid with mixed nanoparticles in porous media using explicit finite difference method","authors":"Ali Haider , M.S. Anwar , Yufeng Nie , Fahad Saleh Almubaddel , Magda Abd El-Rahman","doi":"10.1016/j.csite.2024.105428","DOIUrl":"10.1016/j.csite.2024.105428","url":null,"abstract":"<div><h3>Purpose:</h3><div>This study investigates the effects of hybrid nanoparticles on thermal performance, focusing on convection, magnetic fields, diffusion, radiation, and chemical reactions in porous media. An <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow></msub><mi>O</mi></mrow></math></span>-based fractional Carreau hybrid nanofluid is utilized to enhance heat transfer for industrial applications like gas turbines and condensers.</div></div><div><h3>Design/Methodology/Approach:</h3><div>The Caputo definition of fractional derivatives models the fluid flow, integrating integer and non-integer dynamics. The governing equations are dimensionally reduced and solved using the explicit finite difference method (EFD), with stability and convergence criteria ensuring accuracy. Key parameters, including the Sherwood and Nusselt numbers, are examined to understand thermal and mass transfer behavior.</div></div><div><h3>Findings:</h3><div>Results show that fractional exponents and thermophysical properties significantly influence flow behavior. Fluid velocity increases with the fractional exponent <span><math><mrow><mo>(</mo><mi>α</mi><mo>)</mo></mrow></math></span> due to reduced resistance, while higher porosity parameter <span><math><mrow><mo>(</mo><msub><mrow><mi>λ</mi></mrow><mrow><mn>4</mn></mrow></msub><mo>)</mo></mrow></math></span> decreases velocity. The temperature gradient decreases by 20.31% with the fractional exponent <span><math><mrow><mo>(</mo><mi>β</mi><mo>)</mo></mrow></math></span> and by 22.87% with the Weissenberg number. Skin friction increases by 28.17% with the magnetic parameter, and higher thermal conductivity enhances temperature profiles.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105428"},"PeriodicalIF":6.4,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.csite.2024.105465
Yaohui Deng , Peisheng Liu , Zhao Zhang , Jiajie Jin , Pengpeng Xu , Lei Yan
3D packaging mainly uses TSVs (Through Silicon via) to vertically interconnect multiple chips, achieving the purpose of signal transmission and electrical connection. As a popular advanced packaging method, its research is of great significance. Although stacked chips can achieve stronger performance in smaller spaces, they can also cause a series of reliability issues, among which thermal stress and warping due to differences in the thermal expansion coefficients of materials can even lead to chip failure. Therefore, it is highly valuable to simulate and analyze the entire 3D packaging model.
In this study, the thermal stress and deformation of the whole three-dimensional package model were simulated by finite element analysis. The results showed that there were significant stress and deformation effects at the joint of the TSV structure at normal temperature, and the stress and deformation reached 209.99 MPa and 0.0018519 mm, respectively. After that, the temperature of the double-sided package system containing 3D package under electrothermal coupling conditions was optimized by heat dissipation design, which verified the ‘quantity first’ scheme of heat dissipation fins and reduced the temperature by 40 %.
{"title":"3D package thermal analysis and thermal optimization","authors":"Yaohui Deng , Peisheng Liu , Zhao Zhang , Jiajie Jin , Pengpeng Xu , Lei Yan","doi":"10.1016/j.csite.2024.105465","DOIUrl":"10.1016/j.csite.2024.105465","url":null,"abstract":"<div><div>3D packaging mainly uses TSVs (Through Silicon via) to vertically interconnect multiple chips, achieving the purpose of signal transmission and electrical connection. As a popular advanced packaging method, its research is of great significance. Although stacked chips can achieve stronger performance in smaller spaces, they can also cause a series of reliability issues, among which thermal stress and warping due to differences in the thermal expansion coefficients of materials can even lead to chip failure. Therefore, it is highly valuable to simulate and analyze the entire 3D packaging model.</div><div>In this study, the thermal stress and deformation of the whole three-dimensional package model were simulated by finite element analysis. The results showed that there were significant stress and deformation effects at the joint of the TSV structure at normal temperature, and the stress and deformation reached 209.99 MPa and 0.0018519 mm, respectively. After that, the temperature of the double-sided package system containing 3D package under electrothermal coupling conditions was optimized by heat dissipation design, which verified the ‘quantity first’ scheme of heat dissipation fins and reduced the temperature by 40 %.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105465"},"PeriodicalIF":6.4,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.csite.2024.105464
Sattam Alharbi , Ali Alshamrani
This research enhances the thermal efficiency of a pyramid solar distiller (PSD) through 4 E (energy, exergy, economic, and environmental) analysis. The modified distiller (MPSD) features suspended trays on three vertical walls, tested with and without heaters, and various water levels (6.2–49.6 L) in the basin. The study also examined MPSD's performance with an external condenser, aided by a fan operating at different speeds (0.25–1.5 rpm). Results showed that the MPSD, with a water depth of 1 cm and 12.4 L in the basin, achieved a 33 % yield improvement and 50.2 % efficiency. Total productivity of MPSD reached 3755 mL/m2 compared to 2820 mL/m2 for the PSD. MPSD with heaters produced 6430 mL/m2, reflecting a 98.5 % increase. The best performance occurred at 1.25 rpm, with a 133 % productivity increase, 66.5 % thermal efficiency, and 4.58 % exergy efficiency. The water cost was $0.23/L for the MPSD, lower than the PSD's $0.34/L. CO₂ emissions were 30.93–32.23 tons per year for different configurations, and enviroeconomic indicators were 447.46–467.33 annually, depending on the setup.
{"title":"4E analysis of productivity and efficiency enhancements in pyramid solar distillation: Innovations in tray design, water heating, and forced condensation integration","authors":"Sattam Alharbi , Ali Alshamrani","doi":"10.1016/j.csite.2024.105464","DOIUrl":"10.1016/j.csite.2024.105464","url":null,"abstract":"<div><div>This research enhances the thermal efficiency of a pyramid solar distiller (PSD) through 4 E (energy, exergy, economic, and environmental) analysis. The modified distiller (MPSD) features suspended trays on three vertical walls, tested with and without heaters, and various water levels (6.2–49.6 L) in the basin. The study also examined MPSD's performance with an external condenser, aided by a fan operating at different speeds (0.25–1.5 rpm). Results showed that the MPSD, with a water depth of 1 cm and 12.4 L in the basin, achieved a 33 % yield improvement and 50.2 % efficiency. Total productivity of MPSD reached 3755 mL/m<sup>2</sup> compared to 2820 mL/m<sup>2</sup> for the PSD. MPSD with heaters produced 6430 mL/m<sup>2</sup>, reflecting a 98.5 % increase. The best performance occurred at 1.25 rpm, with a 133 % productivity increase, 66.5 % thermal efficiency, and 4.58 % exergy efficiency. The water cost was $0.23/L for the MPSD, lower than the PSD's $0.34/L. CO₂ emissions were 30.93–32.23 tons per year for different configurations, and enviroeconomic indicators were 447.46–467.33 annually, depending on the setup.</div></div>","PeriodicalId":9658,"journal":{"name":"Case Studies in Thermal Engineering","volume":"64 ","pages":"Article 105464"},"PeriodicalIF":6.4,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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