International Journal of Thermal Sciences最新文献_第6页

Numerical simulation of cellular automata-multiple relaxation time lattice Boltzmann for three-dimensional dendrite motion

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-27 DOI: 10.1016/j.ijthermalsci.2025.109737

Shijie Zhang, Yunbo Li, Siyu Zhang, Baofeng Zhu, Ri Li

A cellular automata-multiple relaxation time lattice Boltzmann three-dimensional coupled model with a dynamic grid has been developed for the objective of simulating the kinematic growth process of binary alloy dendrites. In this model, the cellular automata approach is applied to calculate the dendrite growth, and the multiple relaxation time lattice Boltzmann approach is utilized to emulate the melt flow. Furthermore, a dynamic grid scheme with one level of refinement in comparison to the global grid is proposed as a means of addressing the issue of dendrite motion with the sharp interface. This approach is intended to reduce the considerable memory requirements associated with three-dimensional simulations, while also facilitating acceleration through the use of a graphics processing unit. Lastly, the constructed model was utilized to emulate the translational, rotational and free settling processes of a three-dimensional individual dendrite within laminar, shear and natural convection flows, as well as the settling of multiple dendrites, respectively. The findings of the simulation indicate that the growth of the dendrites in solid solution alloys is predominantly influenced by the local solute composition. Moreover, the impact of dendrite movement on its growth rate is primarily associated with the relative velocity of the dendrite and the melt.

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引用次数: 0

Artificial neural network predictions for temperature: Utilizing numerical analysis in immersion cooling systems using mineral oil and an engineered fluid for 32700 LiFePO4

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-26 DOI: 10.1016/j.ijthermalsci.2025.109742

Muhammed Donmez, Merve Tekin, Mehmet Ihsan Karamangil

Immersion cooling offers high cooling efficiency, due to direct contact with the heat source. This investigation includes the performance of 32700 LiFePO₄ battery cells using immersion cooling with two dielectric fluids: mineral oil (MO), and an engineered fluid (EF). The investigation includes a numerical analysis of 16S1P arranged battery cells under different mass flow rates (0.001, 0.008, and 0.01 kg/s) and discharge rates (1C, 2C, 3C, and 4C). Results show that immersion cooling effectively maintains temperature homogeneity within and between cells. At a mass flow rate of 0.01 kg/s, the average temperature rise stays below 5 °C at a 3C discharge rate and below 10 °C at a 4C-rate across for both fluids. Additionally, an artificial neural network (ANN) model is developed to predict the average temperature of the battery cells with high accuracy. Using coolant type, C-rate, flow rate, and time as input parameters, the ANN achieves good predictive performance with consistently high R-values and low mean squared error across training, validation, and testing datasets. ANN predictions are in good agreement with numerical results, and the maximum prediction error is less than 1 K. This research has shown that flow rate and coolant selection are the most critical parameters in optimizing thermal management, demonstrating the accuracy of ANN in temperature predictions. The present results therefore provide a basis for further investigation into the development of more effective cooling methods, different dielectric fluids, and advanced ANN architectures for performance and safety improvements in LiFePO₄ battery modules.

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引用次数: 0

Compact integrated electromagnetic driving of liquid metal for high heat-flux dissipation

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-26 DOI: 10.1016/j.ijthermalsci.2025.109725

Chuan-Ke Liu, Zhi-Zhu He

Liquid metal (LM) has been widely utilized in scenarios involving overloaded thermal energy delivery and high heat flux thermal management due to its excellent thermal properties. However, the high-performance driving method limits LM-based thermal management. In this paper, a compact integrated rotating permanent magnet induction electromagnetic pump (PM-EMP) is developed for LM. In addition, a three-dimensional multi-physical field numerical method and accurate analytical prediction correlation are built to optimize PM-EMP performance. We systematically investigate the magnetohydrodynamic generation process and factors influencing performance. The results demonstrate that optimizing electromagnetic parameters significantly weakens non-sinusoidal distribution, thereby promoting high output characteristics and flow stability in PM-EMP. By binding the tangential component within the short-circuit strip, we enhance and uniformly distribute the vertical component of current density along channel width, improving current density by 110 %. This optimization facilitates near-wall current distribution to suppress lateral end effects. Notably, strengthening magnetic flux and current density distribution/intensity reduces local pressure pulsation, thus enhancing driving characteristics and flow stability. Considering the influence of lateral end effect and geometric parameters, the performance prediction accuracy obtained by modified analytical correlation can achieve more than 90 % improvement by 28.9 %. Furthermore, we validate the effectiveness of theoretical methods by prototype performance testing.

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引用次数: 0

Multiscale thermal analysis of diamond/Cu composites for thermal management applications by combining lattice Boltzmann and finite element methods

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-25 DOI: 10.1016/j.ijthermalsci.2025.109736

Yidan Zhu , Ershuai Yin , Wenzhu Luo, Qiang Li

To meet the cooling demands of high-power electronic devices, diamond/Cu composites (D/Cu) have attracted extensive attention as next-generation thermal management materials. However, the heat transfer mechanism of D/Cu across micro-nano and macro scales remains unclear. This study establishes a physical geometric model of D/Cu and investigates the impact of micro-nano scale diamond particles on thermal conductivity by integrating the mesoscopic lattice Boltzmann method with macroscopic finite element method. The results show that the sharp edges of the particles tend to reflect and scatter phonons, thereby influencing heat transfer. The thermal conductivity of the composite increases with the diamond particle size and exhibits a particle size threshold; diamond particles contribute to the improvement of thermal conductivity only when their size exceeds 22 μm. Additionally, secondary diamond particles effectively enhance thermal conductivity; on the other hand, the interfacial area introduced cannot be ignored. For a fixed diamond volume fraction, smaller particle size ratio of bimodal diamond particles lead to greater improvements in thermal performance.

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引用次数: 0

Thermal runaway behavior of ternary lithium-ion pouch cell characterized by multi-parameters under penetration

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-25 DOI: 10.1016/j.ijthermalsci.2025.109732

Yan Huang, Min Lv, Guoping Chen, Chunrong Hua, Bing Yan, Dawei Dong

With the rapid development of new energy vehicles, the safety issues of pouch-type lithium-ion batteries have attracted increasing attention. In this study, a 10 Ah pouch-type lithium-ion battery used in vehicles is taken as the research object. Experimental setups are designed to investigate the thermal runaway behavior under different penetration speeds, characterized by multiple parameters including voltage, temperature, gas expansion, and internal resistance. Results reveal four possible scenarios during needle puncture, with the existence of a critical penetration speed range 10–20 mm/s capable of rapidly triggering thermal runaway. Voltage variations exhibit three distinct forms, wherein higher puncture speeds corresponded to greater initial voltage drop rates and larger magnitudes, especially with the voltage dropped to 1809.15 mV in 5.62 s at 40 mm/s. Additionally, at slower puncture speeds, battery rupture location has a significant influence on the voltage drop trend, producing a deviation of about 10 s in the time of voltage plunge when the side rupture and top rupture occurred at 1 mm/s. The penetration speeds and the portions of the steel needle inside the battery being covered by elongated separator affects numbers of battery cells short-circuited within the same timeframe, altering heat generation and heat diffusion. Gas expansion during thermal runaway follows a three-stage process. The onset of expansion closely aligns with the time of the sharp voltage drop with a difference of less than 1 s, while the time difference between the sharp voltage drop and the peak gas expansion decreases with increasing penetration speed, from 4.75 s to 0.94 s. The internal resistance of the battery exhibits a consistent pattern of initial increase followed by decrease during needle puncture. These findings hold significant implications for safety design and parameter warning of pouch-type lithium-ion batteries in vehicles.

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引用次数: 0

Numerical and experimental investigation of heat transfer and flow in oscillating laser dual-wire deposition

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-25 DOI: 10.1016/j.ijthermalsci.2025.109741

Wenhao Huang , Haihui Zhong , Xiaoxu Li , Yazhou Jia , Shiqi Sun , Na Wu

The oscillating laser heat source covers a large area, effectively reducing peak temperature and temperature gradient, while dual-wire additive manufacturing improves wire melting efficiency and forming quality. Therefore, this paper addresses the issues of low wire melting efficiency and poor forming quality in aluminum alloy wire melting additive manufacturing. Using 5A06 aluminum alloy as the research subject, a process combining oscillating laser and dual-wire techniques is proposed. Experimental and simulation analyses are conducted to evaluate this process, leading to the development of a coupled thermal-fluid model for the oscillating laser dual-wire additive manufacturing. Simulations of the temperature and flow fields are performed for various oscillation paths, frequencies, and amplitudes. The results demonstrate that, under the circular oscillation mode, the heat distribution within the molten pool is more uniform, the flow field remains stable, and the overall forming quality is superior. As the oscillation frequency increases, the width of the deposited layer decreases, while its height increases. Additionally, the melt pool's range, depth, and peak temperature exhibit a negative correlation with the oscillation frequency. Increasing the oscillation amplitude leads to a reduction in the melt pool's range, depth, and peak temperature, with the most stable flow and pool condition observed at an amplitude of 1.5 mm. This research provides both theoretical insight and guidance for the optimization of the oscillating laser dual-wire additive manufacturing process for aluminum alloys.

{"title":"Numerical and experimental investigation of heat transfer and flow in oscillating laser dual-wire deposition","authors":"Wenhao Huang , Haihui Zhong , Xiaoxu Li , Yazhou Jia , Shiqi Sun , Na Wu","doi":"10.1016/j.ijthermalsci.2025.109741","DOIUrl":"10.1016/j.ijthermalsci.2025.109741","url":null,"abstract":"<div><div>The oscillating laser heat source covers a large area, effectively reducing peak temperature and temperature gradient, while dual-wire additive manufacturing improves wire melting efficiency and forming quality. Therefore, this paper addresses the issues of low wire melting efficiency and poor forming quality in aluminum alloy wire melting additive manufacturing. Using 5A06 aluminum alloy as the research subject, a process combining oscillating laser and dual-wire techniques is proposed. Experimental and simulation analyses are conducted to evaluate this process, leading to the development of a coupled thermal-fluid model for the oscillating laser dual-wire additive manufacturing. Simulations of the temperature and flow fields are performed for various oscillation paths, frequencies, and amplitudes. The results demonstrate that, under the circular oscillation mode, the heat distribution within the molten pool is more uniform, the flow field remains stable, and the overall forming quality is superior. As the oscillation frequency increases, the width of the deposited layer decreases, while its height increases. Additionally, the melt pool's range, depth, and peak temperature exhibit a negative correlation with the oscillation frequency. Increasing the oscillation amplitude leads to a reduction in the melt pool's range, depth, and peak temperature, with the most stable flow and pool condition observed at an amplitude of 1.5 mm. This research provides both theoretical insight and guidance for the optimization of the oscillating laser dual-wire additive manufacturing process for aluminum alloys.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"211 ","pages":"Article 109741"},"PeriodicalIF":4.9,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138694","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}

引用次数: 0

Development of a renewable technology for air heating and thermal cooling of sub-arctic mines using spray freezing

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-24 DOI: 10.1016/j.ijthermalsci.2025.109704

Mohammaderfan Mohit , Saad Akhtar , Minghan Xu , Agus P. Sasmito

Mining industry is associated with high energy consumption and greenhouse gas (GHG) emissions due to intensive extraction processes and reliance on fossil fuel, specifically propane and diesel. In remote mines located in sub-arctic climates, heating and cooling operations can take up to half of this energy consumption, highlighting the importance of exploring innovative clean alternatives. The present study investigates one emerging solution to address this energy demand, known as spray freezing, in which the solidification of water droplets is used to provide the heating and cooling needs of mines. A multiscale thermo-hydraulic framework for spray freezing is developed, coupling the multi-stage droplet solidification process with a reduced-order spray-droplet dynamics model. Parametric studies are conducted using the Monte-Carlo method to quantify the effects of operating parameters on the system performance. It is found that the heat rate and cooling capacity of the spray freezing system are predominantly influenced by water flow rate and air temperature. Increasing the water flow rate from 7.5 kg/s to 30 kg/s can increase the heat rate to up to 400%. The ice generation of the system depends most on the air temperature, increasing significantly when the temperature drops below the water nucleation point, approximately -14 °C. Eventually, a multi-variate regression method is used to derive three user-friendly correlations that predict the heat rate, outlet air temperature, and ice generation of the spray freezing system, allowing a quick evaluation of the system performance in on-site applications.

{"title":"Development of a renewable technology for air heating and thermal cooling of sub-arctic mines using spray freezing","authors":"Mohammaderfan Mohit , Saad Akhtar , Minghan Xu , Agus P. Sasmito","doi":"10.1016/j.ijthermalsci.2025.109704","DOIUrl":"10.1016/j.ijthermalsci.2025.109704","url":null,"abstract":"<div><div>Mining industry is associated with high energy consumption and greenhouse gas (GHG) emissions due to intensive extraction processes and reliance on fossil fuel, specifically propane and diesel. In remote mines located in sub-arctic climates, heating and cooling operations can take up to half of this energy consumption, highlighting the importance of exploring innovative clean alternatives. The present study investigates one emerging solution to address this energy demand, known as spray freezing, in which the solidification of water droplets is used to provide the heating and cooling needs of mines. A multiscale thermo-hydraulic framework for spray freezing is developed, coupling the multi-stage droplet solidification process with a reduced-order spray-droplet dynamics model. Parametric studies are conducted using the Monte-Carlo method to quantify the effects of operating parameters on the system performance. It is found that the heat rate and cooling capacity of the spray freezing system are predominantly influenced by water flow rate and air temperature. Increasing the water flow rate from 7.5 kg/s to 30 kg/s can increase the heat rate to up to 400%. The ice generation of the system depends most on the air temperature, increasing significantly when the temperature drops below the water nucleation point, approximately -14 °C. Eventually, a multi-variate regression method is used to derive three user-friendly correlations that predict the heat rate, outlet air temperature, and ice generation of the spray freezing system, allowing a quick evaluation of the system performance in on-site applications.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"211 ","pages":"Article 109704"},"PeriodicalIF":4.9,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138079","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}

引用次数: 0

A high precision infrared emissivity measurement method for micro/nano structures

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-24 DOI: 10.1016/j.ijthermalsci.2025.109740

Yinxue Bai , Gangquan Wang , Yue Liu , Longfei Li , Kaihua Zhang , Baolin Zhao , Yufang Liu , Kun Yu

The potential of micro/nano structures in regulating thermal radiation for infrared stealth, radiation cooling, and energy harvesting has attracted significant research interest. However, the radiation from optical components and the surrounding environment poses a challenge to the accurate measurement of thermal radiation of micro/nano samples in laboratory environments. In this study, a background-separated spectral emissivity measurement method was designed, employing two standard reference samples to isolate the sample background and optical component background from the measurement signal of the Fourier Transform Infrared (FTIR) spectrometer. Accurate measurement of infrared spectral emissivity was achieved by analyzing the temperature variations of the sample and optical component backgrounds. To validate this method, a Pt/Cr/Si emitter was designed and fabricated. The measured spectral emissivity of the micro/nano sample was consistent with the simulation results, demonstrating the effectiveness of the background-separated emissivity measurement method. This study provides an effective approach for measuring the spectral emissivity of micro/nano samples above room temperature and separating the thermal radiation background during the measurement process.

{"title":"A high precision infrared emissivity measurement method for micro/nano structures","authors":"Yinxue Bai , Gangquan Wang , Yue Liu , Longfei Li , Kaihua Zhang , Baolin Zhao , Yufang Liu , Kun Yu","doi":"10.1016/j.ijthermalsci.2025.109740","DOIUrl":"10.1016/j.ijthermalsci.2025.109740","url":null,"abstract":"<div><div>The potential of micro/nano structures in regulating thermal radiation for infrared stealth, radiation cooling, and energy harvesting has attracted significant research interest. However, the radiation from optical components and the surrounding environment poses a challenge to the accurate measurement of thermal radiation of micro/nano samples in laboratory environments. In this study, a background-separated spectral emissivity measurement method was designed, employing two standard reference samples to isolate the sample background and optical component background from the measurement signal of the Fourier Transform Infrared (FTIR) spectrometer. Accurate measurement of infrared spectral emissivity was achieved by analyzing the temperature variations of the sample and optical component backgrounds. To validate this method, a Pt/Cr/Si emitter was designed and fabricated. The measured spectral emissivity of the micro/nano sample was consistent with the simulation results, demonstrating the effectiveness of the background-separated emissivity measurement method. This study provides an effective approach for measuring the spectral emissivity of micro/nano samples above room temperature and separating the thermal radiation background during the measurement process.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"211 ","pages":"Article 109740"},"PeriodicalIF":4.9,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138692","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}

引用次数: 0

Fabrication and characterization of novel rectangular cross-sectional microchannel wicks for ultrathin flat heat pipes

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-24 DOI: 10.1016/j.ijthermalsci.2025.109718

Jiaxi Du , Huayong Yan , Sirong Qu , Binjian Ma , Huizhu Yang , Yue Yang , Jialin Liang , Yonggang Zhu

Ultra-thin flat heat pipes (UFHPs) with extremely low thickness have become critical in the thermal management solution to highly integration of electronic devices. Improving the thermal performance of the UFHP requires a thinner wick to maintain vapor space inside, while the capillary performance of the wick cannot deteriorate. In this work, a novel rectangular cross-sectional microchannel wick (RCMW) featuring an array of radially closed micro-capillary tubes is proposed to improve the thermal performance of UFHPs. Five RCMW samples with different cross-sectional sizes are fabricated with a novel template-assisted electrochemical deposition-based method. The effect of the RCMW cross-sectional dimension on the capillary performance is investigated. A capillary rise test is performed to quantitatively characterize the capillary performance of the RCMW. The height of RCMW has a more significant effect on the capillary performance than the width. The capillary performance of RCMWs outstands those from most of the previously reported works. Among these samples, the optimal capillary performance parameter

κ / r_{e ff}

= 2.982 μm is obtained with only 60 μm in thickness. The capillary limit of RCMW is also predicted theoretically, with a critical heat flux of 17.6 W/cm² obtained. These experimental and theoretical studies demonstrate the superiority of RCMW in terms of reducing wick thickness and improving UFHP capillary limit, as well as indicating the direction for further optimization.

{"title":"Fabrication and characterization of novel rectangular cross-sectional microchannel wicks for ultrathin flat heat pipes","authors":"Jiaxi Du , Huayong Yan , Sirong Qu , Binjian Ma , Huizhu Yang , Yue Yang , Jialin Liang , Yonggang Zhu","doi":"10.1016/j.ijthermalsci.2025.109718","DOIUrl":"10.1016/j.ijthermalsci.2025.109718","url":null,"abstract":"<div><div>Ultra-thin flat heat pipes (UFHPs) with extremely low thickness have become critical in the thermal management solution to highly integration of electronic devices. Improving the thermal performance of the UFHP requires a thinner wick to maintain vapor space inside, while the capillary performance of the wick cannot deteriorate. In this work, a novel rectangular cross-sectional microchannel wick (RCMW) featuring an array of radially closed micro-capillary tubes is proposed to improve the thermal performance of UFHPs. Five RCMW samples with different cross-sectional sizes are fabricated with a novel template-assisted electrochemical deposition-based method. The effect of the RCMW cross-sectional dimension on the capillary performance is investigated. A capillary rise test is performed to quantitatively characterize the capillary performance of the RCMW. The height of RCMW has a more significant effect on the capillary performance than the width. The capillary performance of RCMWs outstands those from most of the previously reported works. Among these samples, the optimal capillary performance parameter <span><math><mrow><mi>κ</mi><mo>/</mo><msub><mi>r</mi><mrow><mi>e</mi><mtext>ff</mtext></mrow></msub></mrow></math></span> = 2.982 μm is obtained with only 60 μm in thickness. The capillary limit of RCMW is also predicted theoretically, with a critical heat flux of 17.6 W/cm<sup>2</sup> obtained. These experimental and theoretical studies demonstrate the superiority of RCMW in terms of reducing wick thickness and improving UFHP capillary limit, as well as indicating the direction for further optimization.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"211 ","pages":"Article 109718"},"PeriodicalIF":4.9,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138078","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}

引用次数: 0

Low-GWP refrigerants performance evaluation: R513A and R515B boiling within smooth and microfinned tubes

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2025-01-22 DOI: 10.1016/j.ijthermalsci.2025.109724

Mahmood Hasan Oudah, Zahraa Kareem Yasser

Environmental concerns and stricter regulations lead the refrigeration industry to consider low-GWP (Global Warming Potential) refrigerants as replacements for traditional high-GWP refrigerants, such as R134a. R513A and R515B have emerged as promising candidates due to their low GWP and non-flammability, making them sustainable alternatives. This study experimentally examines the boiling heat transfer characteristics of R513A and R515B during flow in smooth and microfinned tubes, which play a crucial role in enhancing heat transfer performance in refrigeration systems. The experimental setup consists of a 400 mm long tube-in-tube heat exchanger with an internal diameter of 4.3 mm and an outer diameter of 5.0 mm. The test conditions consist of mass fluxes (MF) ranging from 152 to 500 kg/m²·s, heat fluxes (HF) between 13 and 40 kW/m², vapor quality from 0.15 to 0.98, and saturation temperatures (T_s) of 10 °C and 20 °C. The results reveal that the microfinned tube substantially enhances the heat transfer coefficient (HTC) compared to the smooth tube, with R515B steadily exhibiting higher HTCs than R513A. In addition, the experimental data were compared with predictions from correlations available in the open literature, highlighting areas of agreement and disagreement.

{"title":"Low-GWP refrigerants performance evaluation: R513A and R515B boiling within smooth and microfinned tubes","authors":"Mahmood Hasan Oudah, Zahraa Kareem Yasser","doi":"10.1016/j.ijthermalsci.2025.109724","DOIUrl":"10.1016/j.ijthermalsci.2025.109724","url":null,"abstract":"<div><div>Environmental concerns and stricter regulations lead the refrigeration industry to consider low-GWP (Global Warming Potential) refrigerants as replacements for traditional high-GWP refrigerants, such as R134a. R513A and R515B have emerged as promising candidates due to their low GWP and non-flammability, making them sustainable alternatives. This study experimentally examines the boiling heat transfer characteristics of R513A and R515B during flow in smooth and microfinned tubes, which play a crucial role in enhancing heat transfer performance in refrigeration systems. The experimental setup consists of a 400 mm long tube-in-tube heat exchanger with an internal diameter of 4.3 mm and an outer diameter of 5.0 mm. The test conditions consist of mass fluxes (MF) ranging from 152 to 500 kg/m<sup>2</sup>·s, heat fluxes (HF) between 13 and 40 kW/m<sup>2</sup>, vapor quality from 0.15 to 0.98, and saturation temperatures (T<sub>s</sub>) of 10 °C and 20 °C. The results reveal that the microfinned tube substantially enhances the heat transfer coefficient (HTC) compared to the smooth tube, with R515B steadily exhibiting higher HTCs than R513A. In addition, the experimental data were compared with predictions from correlations available in the open literature, highlighting areas of agreement and disagreement.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"211 ","pages":"Article 109724"},"PeriodicalIF":4.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138077","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}

引用次数: 0