International Communications in Heat and Mass Transfer最新文献

英文中文

Three-dimensional simulations of double-diffusive convection of nanofluids and conjugate heat transfer in an n-shaped cavity with non-uniform boundary conditions using the multigrid method

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-06 DOI: 10.1016/j.icheatmasstransfer.2025.108627

Yen-De Chou , Wei-Shien Hwang , Maxim Solovchuk

Nanofluids are a new type of fluid designed to enhance heat transfer. Brownian motion is one of the key mechanisms by which nanofluids enhance heat transfer. In engineering applications involving double-diffusive convection, the temperature and concentration distributions on the surfaces of objects are often non-uniform. The aim of this study is to develop a fast solver to investigate: (1) the effects of non-uniform heating, non-uniform concentration, and Brownian motion on the heat and mass transfer in nanofluids within a three-dimensional n-shaped cavity, and (2) the effects of the composition and arrangement of multi-layer solids on the conjugate heat transfer. The results show that the multigrid method can accelerate the computations by a factor of 1000. Compared to uniform heating and uniform concentration, non-uniform heating and non-uniform concentration can enhance the heat transfer rate by 23.73% and the mass transfer rate by 28.04%. The heat transfer rate of the 5-layer solid is 6.91% higher than that of the 3-layer solid. This study provides important guidance for improving heat and mass transfer efficiency, with potential applications in cooling of electronic devices, solar collectors, and chemical reactors.

{"title":"Three-dimensional simulations of double-diffusive convection of nanofluids and conjugate heat transfer in an n-shaped cavity with non-uniform boundary conditions using the multigrid method","authors":"Yen-De Chou , Wei-Shien Hwang , Maxim Solovchuk","doi":"10.1016/j.icheatmasstransfer.2025.108627","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108627","url":null,"abstract":"<div><div>Nanofluids are a new type of fluid designed to enhance heat transfer. Brownian motion is one of the key mechanisms by which nanofluids enhance heat transfer. In engineering applications involving double-diffusive convection, the temperature and concentration distributions on the surfaces of objects are often non-uniform. The aim of this study is to develop a fast solver to investigate: (1) the effects of non-uniform heating, non-uniform concentration, and Brownian motion on the heat and mass transfer in nanofluids within a three-dimensional n-shaped cavity, and (2) the effects of the composition and arrangement of multi-layer solids on the conjugate heat transfer. The results show that the multigrid method can accelerate the computations by a factor of 1000. Compared to uniform heating and uniform concentration, non-uniform heating and non-uniform concentration can enhance the heat transfer rate by 23.73% and the mass transfer rate by 28.04%. The heat transfer rate of the 5-layer solid is 6.91% higher than that of the 3-layer solid. This study provides important guidance for improving heat and mass transfer efficiency, with potential applications in cooling of electronic devices, solar collectors, and chemical reactors.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"162 ","pages":"Article 108627"},"PeriodicalIF":6.4,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348382","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

A Blasius boundary layer flow of solar radiative heat flux over heated flat plate with partial slip condition

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-05 DOI: 10.1016/j.icheatmasstransfer.2025.108614

Mair Khan , T. Salahuddin , Muhammad Awais , M. Afzal , Basem Al Alwan , Sadia Ayub

In this paper, we describe the behavior of Blasius flow of tangent hyperbolic fluid over a semi-infinite heated flat plate with solar radiation effect. We include the thermo-physical properties along with modifications in energy and concentration equations. We determine the steady flow profile under the partial slip conditions. A special case of Gaputo fractional derivative is added in the current study. The current study is not only important because of its technological significance but also due to its mathematical features described in the form of equations. The boundary layer equations are transformed into a set of ordinary differential equations which are solved numerically with the help of fifth order Rung-Kutta-Fehlberg along with Newton Raphson scheme. Also we discuss the particular case for

n = 1

by using the fractional Blasius model. The obtained result of this study describes that the power law index increases the velocity of fluid whereas the boundary layer thickness decreases. The inclusion of slip velocity indicates that the slip parameter increases the base-flow boundary layer thickness, and the fluid behaves as inviscid. The solar radiation parameter increases the thermal boundary layer thickness. The temperature and concentration boundary layer thickness increases with increase in the value's thermal conductivity and diffusivity parameters. Comparison is made with some recently published papers.

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引用次数: 0

Evaluating fire gas spread in multi-story buildings: A numerical analysis of sprinkler systems in shield fire conditions

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-05 DOI: 10.1016/j.icheatmasstransfer.2025.108630

Hamid Tajaddod, Ghassem Heidarinejad, Mohammad Safarzadeh

The study of fire dynamics in multi-story buildings is crucial due to the complexity of smoke and heat accumulation. This numerical analysis utilized the Fire Dynamics Simulator (FDS) software to evaluate the impact of sprinkler systems on controlling both shielded and unshielded fires in a ten-story building with 50 rooms. Key parameters, including temperature and toxic gas concentrations (CO and CO₂), were measured throughout the building. The findings highlighted that CO₂ levels pose a significant risk in multi-story structures. Additionally, the research revealed that the height of the fuel shield affects sprinkler effectiveness: when the fuel bed is centrally or distally located, increased shield height prolongs fire suppression time. In contrast, if the fuel bed is near the door, variations in shield height have minimal impact on extinguishment duration. Importantly, the sprinkler system not only controls the fire but also mitigates the spread of hot and toxic gases to upper floors. Thus, the study underscores the critical role of sprinklers in enhancing fire safety, particularly in scenarios involving shielded fires.

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引用次数: 0

Exploring Turbulence and micro-scale mixing mechanisms for enhancing jet impingement heat transfer using micro-roughness elements: A data-driven and numerical analysis

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-05 DOI: 10.1016/j.icheatmasstransfer.2025.108646

K. Nagesha

This study uses machine learning to quantify micro-scale mixing mechanisms that enhance jet impingement heat transfer. Experiments and computational fluid dynamics (CFD) simulations tested flat, discrete protrusion, and continuous V-groove surfaces under Reynolds numbers(ReN) from 10,000 to 27,500 and nozzle-to-plate distances(NPD) between 2 and 5 times the diameter of the nozzle. An integrated approach combining experimental data, CFD, and four neural network models was used for comprehensive turbulence analysis. The neural networks, trained on the combined sixty datasets, showed high predictive accuracy with R-squared over 0.999 and Mean Absolute Error over 1e-7. The results highlight that micro-scale turbulence, characterized by Reynolds stress, dominates over operating parameters such as ReN and NPD in enhancing heat transfer. Discrete protrusions actively disrupt the thermal boundary layer, promoting vigorous mixing, while weaker turbulence and insulation effects in V-grooves contribute less. Percentage change analysis shows protrusions are more effective at extracting energy from jet and generating turbulence at smaller NPDs, but V-groove performance increases more strongly with rising distance. This data-driven analysis provides insight into surface roughness-induced mixing mechanisms and compares key turbulence parameters to assess thermal performance. The advanced understanding will aid in developing optimized designs for improved heat transfer in practical applications.

{"title":"Exploring Turbulence and micro-scale mixing mechanisms for enhancing jet impingement heat transfer using micro-roughness elements: A data-driven and numerical analysis","authors":"K. Nagesha","doi":"10.1016/j.icheatmasstransfer.2025.108646","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108646","url":null,"abstract":"<div><div>This study uses machine learning to quantify micro-scale mixing mechanisms that enhance jet impingement heat transfer. Experiments and computational fluid dynamics (CFD) simulations tested flat, discrete protrusion, and continuous V-groove surfaces under Reynolds numbers(ReN) from 10,000 to 27,500 and nozzle-to-plate distances(NPD) between 2 and 5 times the diameter of the nozzle. An integrated approach combining experimental data, CFD, and four neural network models was used for comprehensive turbulence analysis. The neural networks, trained on the combined sixty datasets, showed high predictive accuracy with R-squared over 0.999 and Mean Absolute Error over 1e-7. The results highlight that micro-scale turbulence, characterized by Reynolds stress, dominates over operating parameters such as ReN and NPD in enhancing heat transfer. Discrete protrusions actively disrupt the thermal boundary layer, promoting vigorous mixing, while weaker turbulence and insulation effects in V-grooves contribute less. Percentage change analysis shows protrusions are more effective at extracting energy from jet and generating turbulence at smaller NPDs, but V-groove performance increases more strongly with rising distance. This data-driven analysis provides insight into surface roughness-induced mixing mechanisms and compares key turbulence parameters to assess thermal performance. The advanced understanding will aid in developing optimized designs for improved heat transfer in practical applications.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"162 ","pages":"Article 108646"},"PeriodicalIF":6.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348381","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

Multi-objective optimization of electrochromic windows in office buildings for different climatic conditions

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-05 DOI: 10.1016/j.icheatmasstransfer.2025.108669

Hamed Bagheri-Esfeh

Electrochromic windows stand out as a subset of smart windows that effectively manage sunlight, thereby contributing significantly to energy efficiency and occupant comfort. In this paper, a methodology is presented for determining the optimal properties of electrochromic windows in six distinct cities characterized by varying climates. The cities under examination include Tehran, Sari, Yazd, Shiraz, Esfahan, and Tabriz. The optimization method uses a multi-objective approach to optimize various design variables for electrochromic windows, such as thickness of glass panes, gas layer properties, and window-to-wall ratio. Additionally, it identifies optimal illuminance, heating, and cooling setpoints to enhance electrochromic window performance. The objectives under consideration include the total annual electricity consumption (E) and the Predicted Percentage of Dissatisfied (PPD) coefficient. To facilitate this optimization, Non-Dominated Sorting Genetic Algorithm II (NSGA-II) is employed, generating a Pareto front. The Discomfort Glare Index (DGI) parameter is subsequently computed at the Pareto points to determine the final optimal solution. The results demonstrate that in Esfahan, the implementation of optimum electrochromic windows yields the most substantial reductions in electricity consumption (27.6 %) and PPD coefficient (29.7 %). Furthermore, Krypton gas is identified as the most suitable gas for deployment in optimal electrochromic windows.

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引用次数: 0

Dynamic heat transfer characteristics of R-410A refrigerant in saturated flow boiling under oscillating mass flux conditions

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-05 DOI: 10.1016/j.icheatmasstransfer.2025.108681

C.A. Chen , Shu-Hao Hsu , T.F. Lin , Wen-Ken Li , Wei-Mon Yan

The study investigates the unsteady saturated flow boiling heat transfer of R-410A in a horizontal annular channel, focusing on the effects of oscillating mass flux. Key parameters, including mean mass flux, amplitude and period of oscillation, input thermal flux, and saturation temperature, are examined to determine their influence on boiling curves and heat transfer coefficients (HTC). Baseline steady-state experiments show that mass flux oscillation has minimal effect on boiling curves beyond nucleate boiling, where fully developed nucleate boiling governs heat transfer. Under oscillatory flow conditions, three distinct flow regimes are identified: single-phase flow, sporadic boiling flow, and persistent boiling flow. Periodic variations in mass flux induce corresponding oscillations in both wall temperature (T_w) and boiling HTC, with larger amplitude and frequency of oscillation enhancing thermal response. At higher thermal flux, wall temperature decreases with reduced mass flux, opposite to the trend observed in single-phase flow. For moderate heat flux levels, oscillations in T_w and HTC are minimal, while larger oscillation periods result in more pronounced fluctuations in temperature and HTC. These findings offer valuable insights into the dynamic heat transfer behavior of R-410A, contributing to the optimization of thermal management systems for industrial applications operating under unsteady flow conditions.

{"title":"Dynamic heat transfer characteristics of R-410A refrigerant in saturated flow boiling under oscillating mass flux conditions","authors":"C.A. Chen , Shu-Hao Hsu , T.F. Lin , Wen-Ken Li , Wei-Mon Yan","doi":"10.1016/j.icheatmasstransfer.2025.108681","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108681","url":null,"abstract":"<div><div>The study investigates the unsteady saturated flow boiling heat transfer of R-410A in a horizontal annular channel, focusing on the effects of oscillating mass flux. Key parameters, including mean mass flux, amplitude and period of oscillation, input thermal flux, and saturation temperature, are examined to determine their influence on boiling curves and heat transfer coefficients (HTC). Baseline steady-state experiments show that mass flux oscillation has minimal effect on boiling curves beyond nucleate boiling, where fully developed nucleate boiling governs heat transfer. Under oscillatory flow conditions, three distinct flow regimes are identified: single-phase flow, sporadic boiling flow, and persistent boiling flow. Periodic variations in mass flux induce corresponding oscillations in both wall temperature (<em>T</em><sub><em>w</em></sub>) and boiling HTC, with larger amplitude and frequency of oscillation enhancing thermal response. At higher thermal flux, wall temperature decreases with reduced mass flux, opposite to the trend observed in single-phase flow. For moderate heat flux levels, oscillations in <em>T</em><sub><em>w</em></sub> and HTC are minimal, while larger oscillation periods result in more pronounced fluctuations in temperature and HTC. These findings offer valuable insights into the dynamic heat transfer behavior of R-410A, contributing to the optimization of thermal management systems for industrial applications operating under unsteady flow conditions.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"162 ","pages":"Article 108681"},"PeriodicalIF":6.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348386","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

Theoretical model for alternate-channel induced capillary pressure difference in flat-plate oscillating heat pipes

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-04 DOI: 10.1016/j.icheatmasstransfer.2025.108683

Jian Qu , Guoqing Zhou , Zhanxiao Kang

Startup failure or operation stagnation at the horizontal orientation or against gravity conditions is a tough challenge for safe and reliable applications of oscillating heat pipes (OHPs). The alternate channel design provides a simple and feasible way to address this problem, however its physical mechanism is still not fully understood. In this study, we developed a theoretical model capable of quantitatively predicting the capillary pressure difference produced by alternate channels in flat-plate OHPs, providing the extra driving power for OHP operation at unfavorable orientations. To determine contact angles of different working fluid mediums and then capillary pressure differences, the surface wetting properties of different fluid-medium/substrate-material combinations were measured. The capillary pressure difference is normally of the order of magnitude of several to tens of Pascal, and it is much smaller than the gravitational potential in terms of the order-of-magnitude analysis. However, it could suppress the Marangoni effect and support circulation motions of slugs/plugs at unfavorable orientations, indicating the high instability of OHP system. This study provides an insight into the physical mechanism of OHP operation using alternate channels, and it will broaden their application fields at both terrestrial and microgravity conditions.

{"title":"Theoretical model for alternate-channel induced capillary pressure difference in flat-plate oscillating heat pipes","authors":"Jian Qu , Guoqing Zhou , Zhanxiao Kang","doi":"10.1016/j.icheatmasstransfer.2025.108683","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108683","url":null,"abstract":"<div><div>Startup failure or operation stagnation at the horizontal orientation or against gravity conditions is a tough challenge for safe and reliable applications of oscillating heat pipes (OHPs). The alternate channel design provides a simple and feasible way to address this problem, however its physical mechanism is still not fully understood. In this study, we developed a theoretical model capable of quantitatively predicting the capillary pressure difference produced by alternate channels in flat-plate OHPs, providing the extra driving power for OHP operation at unfavorable orientations. To determine contact angles of different working fluid mediums and then capillary pressure differences, the surface wetting properties of different fluid-medium/substrate-material combinations were measured. The capillary pressure difference is normally of the order of magnitude of several to tens of Pascal, and it is much smaller than the gravitational potential in terms of the order-of-magnitude analysis. However, it could suppress the Marangoni effect and support circulation motions of slugs/plugs at unfavorable orientations, indicating the high instability of OHP system. This study provides an insight into the physical mechanism of OHP operation using alternate channels, and it will broaden their application fields at both terrestrial and microgravity conditions.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"162 ","pages":"Article 108683"},"PeriodicalIF":6.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348368","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

Parametric optimization of charging efficiency in latent heat thermal storage units using elliptical tubes and innovative fin configurations

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-04 DOI: 10.1016/j.icheatmasstransfer.2025.108642

Runping Niu , Tingjun Wu , Chaofan Liu , Jianning Dong , Yan Zhang

The low thermal conductivity of phase change materials (PCM) limits the efficiency of latent heat thermal energy storage systems (LHTESS). This study addresses this challenge by optimizing the geometry of shell-and-tube storage units (TSU) to enhance charging efficiency. Using ANSYS Fluent and the enthalpy-porosity method, we investigated the effects of elliptical tube configurations and fin structures on PCM melting performance. Results revealed that optimizing the aspect ratio (AR) of the elliptical inner and outer tubes to 1:1.8 reduced charging time by 10.1 % compared to circular tubes. Introducing fins with a 150° opening angle further decreased charging time by 36.4 % compared to finless elliptical tubes and improved efficiency by 54.42 % over the baseline circular model. The study highlights the critical role of natural convection in enhancing heat transfer and provides actionable design insights for efficient LHTESS.

引用次数: 0

Investigation of the heat transfer of a single U-tube borehole heat exchanger for medium-shallow geothermal energy

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-04 DOI: 10.1016/j.icheatmasstransfer.2025.108644

Yuxue Gao , Wenke Zhang , Haiqing Yao , Zenggang Zhang , Ping Cui , Mingzhi Yu

The full scientific utilization of geothermal energy is an indispensable part of realizing the “double carbon” goal, based on its remarkable characteristics of energy saving and environmental protection. The study and utilization of medium-shallow geothermal energy (150–1500 m) has attracted increasing interest. Medium-shallow borehole heat exchanger (MSBHE) can meet the demand of both building cooling and heating, with a greater heat exchange capacity, a lower initial investment, and a greater capacity to withstand imbalance between heat extraction and rejection, which combines the advantages of both shallow borehole heat exchanger (SBHE) and medium-deep borehole heat exchanger (MDBHE). The paper focuses on single U-tube MSBHE. A quasi-three-dimensional heat transfer model of MSBHE is proposed, and then experiments are carried out to verify the rationality and correctness of the heat transfer model. Subsequently, calculations are carried out using the model to study heat extraction in winter and heat rejection in summer for the MSBHE. The variations in the inlet and outlet temperatures of the circulating fluid with operating time are also studied. Moreover, diagrams are presented to show the relationships between the nominal heat exchange capacity (NHEC) and key parameters, such as borehole depth, circulating fluid flow rate, space between the two branches of the U-tube, U-tube size, grout, geothermal heat flux and average annual atmospheric temperature, which are helpful in engineering practice.

{"title":"Investigation of the heat transfer of a single U-tube borehole heat exchanger for medium-shallow geothermal energy","authors":"Yuxue Gao , Wenke Zhang , Haiqing Yao , Zenggang Zhang , Ping Cui , Mingzhi Yu","doi":"10.1016/j.icheatmasstransfer.2025.108644","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108644","url":null,"abstract":"<div><div>The full scientific utilization of geothermal energy is an indispensable part of realizing the “double carbon” goal, based on its remarkable characteristics of energy saving and environmental protection. The study and utilization of medium-shallow geothermal energy (150–1500 m) has attracted increasing interest. Medium-shallow borehole heat exchanger (MSBHE) can meet the demand of both building cooling and heating, with a greater heat exchange capacity, a lower initial investment, and a greater capacity to withstand imbalance between heat extraction and rejection, which combines the advantages of both shallow borehole heat exchanger (SBHE) and medium-deep borehole heat exchanger (MDBHE). The paper focuses on single U-tube MSBHE. A quasi-three-dimensional heat transfer model of MSBHE is proposed, and then experiments are carried out to verify the rationality and correctness of the heat transfer model. Subsequently, calculations are carried out using the model to study heat extraction in winter and heat rejection in summer for the MSBHE. The variations in the inlet and outlet temperatures of the circulating fluid with operating time are also studied. Moreover, diagrams are presented to show the relationships between the nominal heat exchange capacity (NHEC) and key parameters, such as borehole depth, circulating fluid flow rate, space between the two branches of the U-tube, U-tube size, grout, geothermal heat flux and average annual atmospheric temperature, which are helpful in engineering practice.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"162 ","pages":"Article 108644"},"PeriodicalIF":6.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349908","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

Flow and heat transfer improvement in microfluidic thermal camouflage film by topology optimization

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2025-02-04 DOI: 10.1016/j.icheatmasstransfer.2025.108626

Lujia Li , Jiaqi Huang , Songjing Li , Jianan Xu

Microfluidic thermal camouflage films conceal infrared targets by circulating liquid within the film, representing a novel approach to microfluidic camouflage technology. A topology optimization method applied to the design of bionic honeycomb structure is proposed to achieve the dual goals of enhancing heat transfer and reducing flow resistance. Firstly, a variable density topology optimization model of the bionic honeycomb structure is established, and the influence of model parameters on the optimization results and convergence is analyzed. A synergistically topology-optimized film, aimed at optimizing thermal uniformity and fluid flow energy consumption, is obtained. Subsequently, numerical studies indicate that the topology-optimized film surpasses the traditional honeycomb structure camouflage film in terms of temperature distribution uniformity and heat transfer performance. To validate the numerical simulation results, a prototype of the optimized honeycomb topology with the ideal morphology is fabricated, and its flow and heat transfer characteristics are experimentally studied. Finally, a thermal camouflage performance test system is constructed to explore the thermal-fluid coupling law and the enhanced heat transfer mechanism of the topology-optimized honeycomb structure. Specifically, the TO film reduced the maximum temperature difference by 28.94 % compared to the traditional film at Re = 2201, reflecting enhanced convective heat transfer efficiency. Additionally, at 600 mL/min, the TO film shortened the thermal equilibrium time to 150 s with a steady-state temperature of 9.4 °C, outperforming the traditional film's 210 s and 10.8 °C. The experimental results confirm the feasibility and effectiveness of the proposed model method, demonstrating that the honeycomb film designed based on the topology optimization method exhibits excellent thermal camouflage performance, which is expected to foster further application of bionic structures in microfluidic camouflage technology.

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