International Journal of Heat and Fluid Flow最新文献

{"title":"A novel air-assisted spray cooling approach using water–acetone mixtures for enhanced photovoltaic thermal management","authors":"Adem Kilic,&nbsp;Kenan Yakut,&nbsp;Muhammet Harun Osta,&nbsp;Ahmet Numan Özakin,&nbsp;Hassen Ghaly","doi":"10.1016/j.ijheatfluidflow.2026.110286","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110286","url":null,"abstract":"<div><div>The increasing demand for sustainable energy has highlighted the need for advanced thermal management in photovoltaic (PV) systems. Excess heat accumulated on PV surfaces reduces carrier mobility and output voltage, thereby limiting energy conversion efficiency. Therefore, innovative cooling strategies that enhance heat transfer while maintaining economic feasibility are crucial for next-generation solar technologies. Various methods, including finned surfaces, phase-change materials, liquid films, and sprays, have been proposed for PV cooling, with air-assisted sprays standing out due to their high heat transfer and low energy demand. However, most existing air-assisted spray cooling studies have focused on pure water, ethanol, or nanofluids, while the thermal behavior of water–acetone binary mixtures remains insufficiently investigated. In this study, an air-assisted spray cooling system using water–acetone mixtures containing 0–45% acetone was experimentally and numerically examined. Four different nozzles were tested, and pressure-fed full-cone nozzles were found to produce smaller droplets and achieve higher heat transfer coefficients. Experiments were conducted under approximately 1000 W/m² irradiance, with a constant air flow rate of 4 m³/h and liquid flow rates between 150 and 800 mL/min. CFD results showed strong agreement with experimental data, with temperature deviations below 2 °C and time differences under 10%. Increasing the liquid flow rate and acetone content reduced the cooling time from 320 s (pure water) to 77 s. Owing to rapid evaporation, 400–600 mL/min flow rates and 15–30% acetone mixtures provided 9–22% faster cooling with only 190–380 USD additional annual operating cost.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110286"},"PeriodicalIF":2.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146169968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Friction-factor and Nusselt-number correlations for low-Reynolds-number flow in curved and helical rectangular channels","authors":"Robert J. Kee,&nbsp;Kasra Taghikhani,&nbsp;Huayang Zhu,&nbsp;Oyvind Nilsen","doi":"10.1016/j.ijheatfluidflow.2026.110255","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110255","url":null,"abstract":"<div><div>This paper derives friction-factor Re<span><math><mi>f</mi></math></span> and Nusselt-number Nu correlations for laminar, fully developed, parallel flow in curved rectangular channels. The correlations depend on the channel geometry as characterized by two dimensionless parameters—the channel aspect ratio <span><math><mi>α</mi></math></span> and the radius of curvature <span><math><mi>ξ</mi></math></span> (<span><math><mrow><mn>0</mn><mo>.</mo><mn>1</mn><mo>≤</mo><mi>α</mi><mo>≤</mo><mn>5</mn></mrow></math></span> and <span><math><mrow><mn>0</mn><mo>.</mo><mn>1</mn><mo>≤</mo><mi>ξ</mi><mo>≤</mo><mn>5</mn></mrow></math></span>). The analysis shows that the dimensionless correlations can be derived from an eigenvalue of the dimensionless conservation equations. The computational approach solves dimensionless circumferential momentum and thermal-energy equations with a high-resolution finite-element method. The analysis is restricted to parallel flow, with the circumferential velocity being the only velocity component (i.e., there are no radial and axial velocities). This assumption necessarily eliminates the possibility of Dean vortices, which are present in curved channels under flow circumstances that include high Reynolds numbers and small radius of curvature. The results are validated by comparisons with known limiting cases and with three-dimensional computational-fluid-dynamics simulations. The paper reports quantitative fits to the derived correlations (i.e., Re<span><math><mi>f</mi></math></span> (<span><math><mrow><mi>α</mi><mo>,</mo><mi>ξ</mi></mrow></math></span>) and Nu(<span><math><mrow><mi>α</mi><mo>,</mo><mi>ξ</mi></mrow></math></span>).</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110255"},"PeriodicalIF":2.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145974047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new nonlinear dissipative boundary condition for internal incompressible flows","authors":"Jacek Szumbarski ,&nbsp;Jakub Gałecki","doi":"10.1016/j.ijheatfluidflow.2026.110274","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110274","url":null,"abstract":"<div><div>This paper presents a numerical methodology for modeling unsteady flows of viscous incompressible fluids within internal domains containing multiple inlet and outlet sections. A new formulation for dissipative boundary conditions, incorporating nonlinear terms, is introduced. The approach enables the imposition of time-dependent flow rates and/or section-averaged pressures at the domain boundaries. The solution technique relies on the instantaneous superposition of Stokes problems. Fluid motion unsteadiness is addressed by combining Backward Differentiation Formulae (BDF) schemes with Operator-Integration-Factor splitting (OIFS) and polynomial extrapolation to manage the model’s nonlinearities. Numerical simulation results, generated using a spectral element solver applied to a two-dimensional test case, are also detailed.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110274"},"PeriodicalIF":2.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Swirl air jets for high heat transfer in solar collectors","authors":"Nagendra Kumar,&nbsp;Satyender Singh,&nbsp;Sanjay Kumar,&nbsp;Ranchan Chauhan","doi":"10.1016/j.ijheatfluidflow.2026.110270","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110270","url":null,"abstract":"<div><div>In the present experimental work, an array of swirl air jets impinging on hot absorber plate is investigated to improve the heat transfer in solar air heater. Swirling nozzles are designed and 3D printed to obtain different velocity and diameter of the air swirls. Various geometrical parameters related to swirling nozzles, such as height of nozzle <span><math><mrow><mo>(</mo><mn>30</mn><mi>m</mi><mi>m</mi><mo>≤</mo><mi>H</mi><mo>≤</mo><mn>50</mn><mi>m</mi><mi>m</mi><mo>)</mo></mrow></math></span> and number of helix <span><math><mrow><mo>(</mo><mn>0</mn><mo>≤</mo><mi>ξ</mi><mo>≤</mo><mn>4</mn><mo>)</mo></mrow></math></span> for three different types of nozzles, i.e., smooth non-swirling (N₁), with twisted tap helix (N₂), and with twisted tap helix and central tube (N₃). The nozzle, N₃ presents a novel design that incorporates both smooth in the center and swirl (helix) configuration around to remove the heated zone that commonly left at the central region in swirl jet impingement. Thermal performance of solar air heater (SAH) for all three nozzles is analyzed and compared for the range of mass flow rate, i.e., <span><math><mrow><mn>0.01</mn><mi>k</mi><mi>g</mi><mo>/</mo><mi>s</mi><mo>≤</mo><mover><mi>m</mi><mo>̇</mo></mover><mo>≤</mo><mn>0.025</mn><mi>k</mi><mi>g</mi><mo>/</mo><mi>s</mi></mrow></math></span>. The results revealed high thermal performance for N₃ which is obtained as 93% and about 40% high in comparison to non-swirling nozzle, N1. Hence, using nozzle, N₃ about 9.5% enhancement is noticed in the thermal performance for the variation in H from 30 to 50 mm. The trends of thermohydraulic efficiency delineated the dominance of N₃ over other nozzle designs at lower mass flow rate and obtained as 68%, when H = 50 mm and <span><math><mi>ξ</mi></math></span> = 2. However, this investigation presents a novel insight in terms of different nozzles design and way forward in the improvement of thermal performance of SAH utilizing mixed swirls and air jets.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110270"},"PeriodicalIF":2.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptive detached eddy simulation of transitional and massively separated flows around the S809 airfoil","authors":"Le He,&nbsp;Gaohua Li,&nbsp;Zifei Yin","doi":"10.1016/j.ijheatfluidflow.2026.110304","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110304","url":null,"abstract":"<div><div>The adaptive, <span><math><mrow><msup><mrow><mi>ℓ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><mi>ω</mi></mrow></math></span> Delayed Detached Eddy Simulation model has the capability of adapting to local flow, and is proven to be capable of simulating orderly and bypass transition on flat plates (<span><span>Yin et al., 2021</span></span>). To answer the question of whether the adaptive, <span><math><mrow><msup><mrow><mi>ℓ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><mi>ω</mi></mrow></math></span> model can predict the evolution of aerodynamic flow around a natural laminar airfoil at different angles of attack, a series of numerical simulations is performed for the S809 airfoil. A key prerequisite of the adaptive <span><math><mrow><msup><mrow><mi>ℓ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><mi>ω</mi></mrow></math></span> model to predict transition is the resolution of precursor large-scale motions in the laminar boundary layer, which triggers the activation of modeled Reynolds stresses and thereby enables transition prediction. The present work explores the use of turbulence inflow generation and a low-dissipation, high-resolution numerical method to enable the simulation of transitional and separated flows around the S809 airfoil. The <span><math><mrow><msup><mrow><mi>ℓ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><mi>ω</mi></mrow></math></span> model is capable of predicting distinct flow states occurring at various angles of attack. It not only captures laminar flow over a realistic airfoil shape, but also resolves spanwise variations in flow behavior.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110304"},"PeriodicalIF":2.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical evaluations of geometry and structure effects on passive cooling efficiency in metal foam finned heat sinks","authors":"Abbas J. Jubear Al-jassani ,&nbsp;Ahmed A.Y. Al-Waaly ,&nbsp;Aqeel M. Uglah ,&nbsp;Goutam Saha","doi":"10.1016/j.ijheatfluidflow.2026.110300","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110300","url":null,"abstract":"<div><div>This study investigates the thermal performance of metal foam–based finned heat sinks under natural convection using both experimental and numerical approaches. The numerical analysis was performed in ANSYS Fluent using the Local Thermal Non-Equilibrium (LTNE) model. Experiments were carried out for four pore densities (5, 10, 15, and 20 PPI) and porosities ranging from 95% to 71%. Four types of metal foams—aluminum, copper, nickel, and titanium—were tested, with air as the working fluid and heat inputs varying from 4 to 30 W. The experimental setup included six aluminum foam fins (100 × 100 × 10 mm³) mounted on an aluminum base plate (100 × 100 × 3.5 mm³), with an 8 mm spacing between fins. Aluminum foam fins with a pore density of 10 PPI and 91% porosity were tested in both covered and uncovered configurations, with the heat sink oriented vertically and horizontally. Results showed that the optimal porosity and pore density were 0.79 and 5 PPI, respectively. Consequently, reducing the porosity from 95% to 79% results in a 16.7% decrease in the base temperature difference, while the Nusselt number (Nu) improves by 21.3%. Additionally, the 5 PPI foam exhibits a 12% higher reduction in average temperature and a slight increase in heat transfer, 1.92% relative to the 20 PPI sample. The horizontal orientation provided better thermal performance than other positions. Using copper instead of aluminum improved the base-to-ambient temperature difference by 3.3%. Conversely, aluminum performed 22% and 3% better than titanium and nickel, respectively. The best ratio of cover height to fin height was found to be 0.8. Accordingly, the convergent rate of results is approximately 98.8% between the heat sink with a cover height ratio of 0.8 and the uncovered heat sink. Additionally, a correlation equation was developed linking the Nusselt number with porosity and Rayleigh number. Overall, the findings highlight the strong potential of metal foam heat sinks, particularly in horizontal configurations, for enhancing natural convection cooling performance in compact electronic and thermal systems.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110300"},"PeriodicalIF":2.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study of transmission-line icing based on Euler method and comparative analysis of multiple methods","authors":"Wuyue Zang ,&nbsp;Feng Xu ,&nbsp;Zhongdong Duan ,&nbsp;Jinping Ou","doi":"10.1016/j.ijheatfluidflow.2026.110275","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110275","url":null,"abstract":"<div><div>In this study, an icing model of a transmission line is established by using the secondary development of the Fluent user-defined scalar (UDS) transport equation. An Eulerian two-phase flow model is established by using the UDS transport equation framework to determine the impact of water droplets and the local water-droplet collection coefficient. As per the Messinger thermodynamic equilibrium principle, a user-defined function is developed to assess the icing amount on the microelements of the wire surface and convert it into the ice thickness. To verify the accuracy of the results, the calculation reference values, results, and procedures of the Lagrangian and Euler methods developed by using the discrete phase model are compared and analyzed. The two-dimensional three-dimensional results are compared to determine the relationship between the three-dimensional effect and particle size of the water droplets.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110275"},"PeriodicalIF":2.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146073599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regression analysis of heat transfer in twin slot jet impingement with computational fluid dynamics and machine learning techniques","authors":"Homin Kim ,&nbsp;Tae Hee Lee ,&nbsp;Sanghoon Kim ,&nbsp;Sang Lee ,&nbsp;Jung-Wuk Hong","doi":"10.1016/j.ijheatfluidflow.2025.110220","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110220","url":null,"abstract":"<div><div>This study proposes a hybrid methodology coupling computational fluid dynamics (CFD) and machine learning to analyze the heat transfer characteristics of unconfined twin slot jets impinging on a heated wall. We develop an accurate numerical model, apply machine learning to identify the key parameters, and subsequently perform a regression analysis across a wide range of operating conditions. Specifically, a high-fidelity two-dimensional CFD model is developed, and the solutions are obtained using the <span><math><mi>k</mi></math></span>–<span><math><mi>ɛ</mi></math></span> turbulence model. The model is validated by comparing the simulated Nusselt number distributions with experimental results on the impingement surface. A large dataset of 1575 simulations is constructed by systematically varying four operating conditions of the jet: jet velocity, nozzle spacing, wall temperature, and jet height. This study employs machine learning for objective feature selection to facilitate the development of interpretable regression models. Four machine learning algorithms, including multi-layer perceptron, random forest, gradient boosting, and support vector regression, are applied to the dataset, identifying jet velocity and jet height as the key parameters governing heat transfer. Focusing on these key parameters, we identify a critical flow transition at a threshold jet height of 12 times the nozzle width, which separates the flow behavior into near- and far-field regimes. For each regime, separate polynomial and power-law regression models are obtained to calculate the average and maximum Nusselt numbers. This methodological approach effectively bridges the gap between data-driven analysis and practical engineering design, providing accurate and effective predictive tools for thermal analysis.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"118 ","pages":"Article 110220"},"PeriodicalIF":2.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145836935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigations on heat transfer in turbulated cutback surface with Chevron-shaped rib configurations for trailing-edge","authors":"Mengjiao Han ,&nbsp;Lin Ye ,&nbsp;Cunliang Liu ,&nbsp;Xuyang Ji ,&nbsp;Zhuan Liu ,&nbsp;Xiyuan Liang","doi":"10.1016/j.ijheatfluidflow.2025.110201","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110201","url":null,"abstract":"<div><div>The current research proposes a unique turbulated cutback structure for trailing-edge cooling, which places chevron-shaped ribs on the cutback surface to improve heat transfer. An experimental system is established, and the reliability of the numerical method is verified via pressure-sensitive paint (PSP) and transient thermochromic liquid–crystal (TLC) experiments. The adiabatic film effectiveness (<em>η</em>), heat transfer coefficient, and flow physics of the cutback surface with various angles of chevron-shaped ribs are obtained via numerical simulations and compared with those of the traditional smooth case to further analyse and understand the film cooling characteristics of the turbulated cutback structure. Three chevron-shaped rib angles of 30°, 45°, and 60° for three blowing ratios (<em>M</em>) are investigated. The effect of chevron-shaped ribs on <em>η</em> is not notable because the rib height is relatively small. The low <em>η</em> with the “M-shape” is manifested downstream of the cutback surface. In the downstream region of the cutback surface, <em>η</em> becomes weaker with increasing angle, but the values are still above 0.9. The chevron-shaped ribs significantly enhance the heat transfer on the cutback surface, and the area-averaged heat transfer coefficient is 26.3–41.2 % greater than that in the smooth case. The 45-deg case produces a higher heat transfer intensity than the other two chevron-shaped rib cases at the studied <em>M</em>. In the region far downstream, the heat transfer intensity of the 30-deg case is higher than that of the other two cases, whereas it is lower downstream of the slot exit, in which the difference decreases as <em>M</em> increases. At <em>M</em> = 1.0, the area-averaged heat transfer intensity of the cases with large angles of 45 deg and 60 deg reaches its peak. The net heat-flux reduction (<em>NHFR</em>) values of the ribbed structure are consistently greater than those of the smooth case, with an improvement of 4.1–8.8 % at low <em>M</em> and a sharp increase to 26.5 % when <em>M</em> reaches 2.0, confirming enhanced comprehensive cooling performance. Additionally, aerodynamic analysis revealed that, compared with smooth ribs, chevron-shaped ribs increase the total pressure loss coefficient by only approximately 2.2 % and the thermal loss coefficient by approximately 6.3 %, indicating minimal adverse effects on aerodynamic performance.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"118 ","pages":"Article 110201"},"PeriodicalIF":2.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the flow boiling characteristics of two-phase cooling loop with mechanically pumped circulation","authors":"Maojin Zeng ,&nbsp;Qian Lyu ,&nbsp;Dan Zhu ,&nbsp;Jiapeng Chang ,&nbsp;Haolei Han ,&nbsp;Yan Dou ,&nbsp;Jinjie Feng ,&nbsp;Botao Xia ,&nbsp;Xiaoling Yu","doi":"10.1016/j.ijheatfluidflow.2025.110191","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110191","url":null,"abstract":"<div><div>With the rapid development of the new energy industry, the increasing power demands higher requirements for thermal management. The phase change system of the mechanically pumped cooling loop (MPCL) has gained widespread attention for its ability to achieve effective flow boiling by precisely regulating the dryness in response to power variations. In this paper, using the R134a as the refrigerant, the flow boiling characteristics of cold plate are experimentally investigated under the MPCL. The flow rate and power intervals are 0.5–1.5 L/min and 180–1690 W, respectively. Meanwhile, the optimal dryness is calculated by visualizing the flow, temperature, and phase fields using the Ansys Fluent. The results show that the higher flow rate weakens latent heat transfer. The heat transfer coefficient (HTC) is increased and then decreased with flow rate. The optimal flow boiling regime is achieved at the inflection point, which is shifted to higher flow rate as power is increased. When the power is too high, the bubble generation rate exceeds the detachment rate, causing massive bubbles to cover the wall and degrade thermal performance. As the flow rate is increased, the critical heat flux (CHF) is also increased, but the maximum value of HTC is decreased. To ensure safe operation of MPCL, the dryness should be controlled within 0.6. The dryness for optimum boiling heat transfer is in the range of 0.2 to 0.3.The pressure drop is increased with both flow rate and power. This study can provide valuable guidance for the design of MPCL systems for high-power chips.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"118 ","pages":"Article 110191"},"PeriodicalIF":2.6,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}