Article
Multidisciplinary Sciences
M. Zubair Akbar Qureshi, S. Bilal, M. Y. Malik, Qadeer Raza, El-Sayed M. Sherif, Yong-Min Li
Summary: Matrix nanocomposites are high performance materials with unique design possibilities. This study analyzes the thermal features of viscous fluid flow between orthogonally rotating disks with inclusion of metallic matrix nanocomposite (MMNC) and ceramic matrix nanocomposites (CMNC) materials. The impact of these materials on flow and heat transfer characteristics is investigated, with the findings suggesting that hybrid nanofluids have significant influence compared to simple nanofluids.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Chemical
Robert Plant, Gregory Hodgson, Stefania Impellizzeri, M. Ziad Saghir
Summary: The use of nanofluids for heat transfer has gained research interest as a potential method for enhancing heat transfer. Various experiments have shown that the use of nanoparticles in a working fluid does not significantly disrupt the system and can improve the heat transfer capabilities of a system. Nano fluids and hybrid nanofluids have been found to offer thermal enhancement without major drawbacks.
Review
Chemistry, Multidisciplinary
Farhan Lafta Rashid, Ahmed Kadhim Hussein, Emad Hasani Malekshah, Aissa Abderrahmane, Kamel Guedri, Obai Younis
Summary: Recent studies have explored various strategies to modify heat-transfer rates in closed cavities, such as adding partitions, fins, or altering forms. Experimental and numerical investigations have shown that fin design can enhance heat transmission and accelerate phase change material melting. Additionally, the optimal wind incidence angle for maximum convective heat loss depends on cavity tilt angle and wind speed.
Article
Thermodynamics
Ayad S. Abedalh, Zaid A. Shaalan, Husam Naufal Saleh Yassien
Summary: The experimental study on convective heat transfer flow of hybrid nanofluids over a backward facing step in a heated rectangular duct under laminar flow showed significant enhancement in heat transfer and pressure drop using a mixture of Al2O3 and TiO2 solid nanoparticles in pure water. The results indicated that the Nusselt number increases with higher Reynolds number and mass fraction, while the friction factor decreases under these conditions. Enhancements of heat transfer and pressure drop were approximately 14% and 4% respectively.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Engineering, Chemical
Xu Ma, Yindong Song, Yang Wang, Shouguang Yao, Kambiz Vafai
Summary: In this study, novel hybrid nanoparticles were prepared using Ag modified functionalized GNP, and the boiling heat transfer properties of the nanofluids were investigated. The GNP-Ag hybrid nanofluids with a weight concentration of 0.001% exhibited the best heat transfer performance, with improved structural modification and wetting properties playing a crucial role in enhancing the heat transfer.
Article
Engineering, Environmental
Hongqiang Chen, Yonghai Zhang, Lei Huang, Xiong Zhao, Xiang Ma, Zihuan Ma, Junsheng Hou, Jinjia Wei, Paolo Di Marco, Omid Mahian, Nanjing Hao
Summary: This article presents a simple and straightforward microfluidic strategy for synthesizing functional silica nanofluids with excellent stability. The use of these nanofluids in microchannel flow boiling significantly enhances the heat transfer coefficient and critical heat flux, providing a promising solution for thermal management in high-power electronics.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Thermodynamics
Nuraini Binti Sukhor, Alhassan Salami Tijani, Jeeventh Kubenthiran, Ibrahim Kolawole Muritala
Summary: The use of emerging technology in the electronic industry has led to the miniaturization of electronic devices, making heat dissipation crucial for maintaining high performance and reliability. This study systematically modeled and investigated the computational heat transfer characteristics of Al2O3-Cu/water hybrid nanofluid in a micro heat sink, finding that Nusselt number increases with Reynolds number and smaller transverse pitch leads to better heat transfer performance.
INTERNATIONAL JOURNAL OF GREEN ENERGY
(2021)
Article
Thermodynamics
Md Jahid Hasan, Shams Forruque Ahmed, Arafat A. Bhuiyan
Summary: This study investigates the heat transfer performance of a helical heat exchanger using nanofluids with different head-ribbed geometries and coil revolutions. The results show that the helical heat exchanger with 2 head ribbed and 30 coil revolution is the most effective design. The use of nanofluids enhances the heat transfer rate, with Al2O3 offering the highest heat transfer rate and SiO2 providing the lowest. The heat transfer rate improves with a decrease in the number of ribbed heads and an increase in coil revolutions.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Review
Thermodynamics
Javier P. Vallejo, Jose I. Prado, Luis Lugo
Summary: Research on nanofluids has mainly focused on traditional mono nanofluids and recently received attention on hybrid nanofluids, aiming to enhance performance through the study of mixed nanomaterials. Experimental studies on the heat transfer performance of these two types of nanofluids have not yet conclusively determined which is more promising for heat transfer applications.
APPLIED THERMAL ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Farida Iachachene, Zoubida Haddad, Muesluem Arici, Mehdi Jamei, Amina Mataoui
Summary: Turbulent forced convective flow of hybrid and single nanofluids in a conical diffuser is numerically investigated. The impact of using theoretical and experimental correlations for dynamic viscosity and thermal conductivity on the heat transfer is studied. Addition of TiO2 nanoparticles decreases the heat transfer inside the diffuser, whereas addition of TiO2-SiO2 nanoparticles either enhances or decreases the heat transfer rate. The Gene Expression Programming model accurately evaluates the relationship between the Nusselt number, Reynolds number, and nanoparticle concentration.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2023)
Article
Engineering, Multidisciplinary
Ahmed H. Abdelaziz, Wael M. El-Maghlany, Ahmed Alaa El-Din, Mohamed A. Alnakeeb
Summary: This study numerically investigates the mixed convective heat transfer and pressure drop of nanofluids in an isothermal horizontal tube. The results show that nanofluids can enhance heat transfer, with the maximum average Nusselt number increase of 15.5% for Al2O3. Ionic nanofluids demonstrate promising results with a significant increase (37%) in the Nusselt number, while hybrid nanofluids show no enhancement.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Engineering, Chemical
Zi Ding, Cong Qi, Tao Luo, Yuxing Wang, Jianglin Tu, Chengchao Wang
Summary: The study showed that TiO2-H2O nanofluids and corrugated pipes significantly improved the heat transfer efficiency of double-pipe heat exchangers.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Thermodynamics
Asif Khan, Muddassir Ali
Summary: The hydraulic and thermal performances of alumina-silica/water hybrid nanofluid in a minichannel heat sink are experimentally investigated. The hybrid nanofluid enhances heat transfer and pressure drop, with heating power having a significant effect on the performance.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Ramaswamy Devakottai Sundaram, Srivatsan Madhavan, Prashant Singh, Srinath Ekkad
Summary: Combining array jet impingement with concentric micro pin-fins leads to enhanced heat dissipation without significant increase in pumping power. Additive manufacturing allows for the production of roughness elements with high accuracy, improving the manufacturability of such configurations. Experimental and numerical studies were conducted to characterize the heat transfer performance and validate the computational model, demonstrating the effectiveness of concentric micro pin-fins in heat transfer applications.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Mingrui Sun, Lunxiang Zhang, Chengzhi Hu, Jiafei Zhao, Dawei Tang, Yongchen Song
Summary: Optimizing the pore structure of metal foam is considered a feasible approach for improving overall heat transfer performance. The study found that throat area could not effectively optimize heat transfer performance, but the area goodness factor j/f was higher than conventional Kelvin cells.
Article
Thermodynamics
Rajesh Nimmagadda, Elena Ionela Chereches, Marius Chereches
Summary: The study found that the uni-directional lid-driven cavity and specific ionic liquids or alumina nanoparticles can significantly enhance heat transfer performance, outperforming pure water.
INTERNATIONAL JOURNAL OF THERMOPHYSICS
(2021)
Article
Mechanics
Veeresh Tekure, K. Venkatasubbaiah
Summary: Numerical study of conjugate heat transfer in supersonic turbulent flow over a flat plate with finite thickness shows lower interface temperature and fluid temperature variation compared to non-conjugate heat transfer analysis. Results indicate significant increase in interface temperature for low thermal conductivity plate materials, and negligible effect of plate thickness on flow field temperature variation. Additionally, the maximum interface temperature increases with plate thickness.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2021)
Article
Thermodynamics
Abhijith Mullakkal Sasidharan, Kondapalli Venkatasubbaiah
Summary: An in-house Fortran-based solver is used to study numerically the forced convection flow of water-based and liquid metal gallium-based alumina-copper hybrid nanofluid through a wide rectangular mini channel in the laminar regime. The addition of copper nanoparticles improves the heat transfer performance of both liquid gallium and pure water, and the heat transfer performance of water-based hybrid nanofluids shows significant changes with variations in Reynolds number and particle concentration.
HEAT TRANSFER ENGINEERING
(2023)
Article
Mechanics
Veeresh Tekure, Pratik Shrikant Pophali, K. Venkatasubbaiah
Summary: The study found a significant reduction in total drag force with an increase in aerospike semi-cone angle at a fixed spike length to blunt-body diameter ratio. Lateral injection improved aerodynamic heat reduction capability, while a small bump on the spike stem proved to be more effective in reducing aerodynamic drag.
Article
Thermodynamics
Stephen Manova, Lazarus Godson Asirvatham, Appadurai Anitha Angeline, Sheno Jerbin, Jefferson Raja Bose, Rajesh Nimmagadda, Russel Jayaseelan, Somchai Wongwises
Summary: This experimental study compared the heat transfer performance of copper screen mesh wick and metal foam inserted evaporator section in miniature loop thermosyphon. Results showed that the metal foam had better heat transfer performance compared to the copper screen mesh wick, making it a superior choice for thermal management in electronic devices.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
R. Harish, Rajesh Nimmagadda, S. Rajesh Reddy
Summary: The turbulent melting characteristics of hybrid nano-enhanced phase change material in a three-dimensional rectangular enclosure are investigated numerically. The addition of hybrid nanoparticles significantly improves the melting rate and thermal performance of the phase change material.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Engineering, Mechanical
C. Chaitanya Reddy, Sarwasva Chowdhary, Rajesh Nimmagadda, R. Harish, S. Rajesh Reddy
Summary: A numerical investigation is conducted to explore how droplet collisions affect the characteristics of hollow cone sprays in the presence of a crossflowing air stream. The study utilizes an Eulerian-Lagrangian point parcel spray solver in the OpenFOAM platform to simulate the process of hollow cone sprays in a crossflow. The LISA-TAB atomization model is used to simulate droplet atomization, and the standard O'Rourke collision algorithm is employed to account for droplet collisions. The numerical simulations are carried out by varying the liquid to gas momentum flux ratio in the range of 17,435-213,587 to examine the effect of crossflow velocity on the hollow cone spray. Qualitative and quantitative comparisons are made between the spray with collision model and the spray without collision model. The spray characteristics, including Sauter mean diameter (SMD), maximum droplet diameter, and length of penetration, are reported. The results show a significant difference in SMD between the spray with and without collision model, with higher droplet dispersion observed in the spray accounting for collision interactions compared to the one without accounting for collisions.
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Ranjit J. J. Singh, Y. S. Kannan, Rajesh Nimmagadda, B. Shukla
Summary: In this study, a three-dimensional numerical analysis is conducted to regulate and suppress heat and mass transfer by varying thermal and solutal buoyancy force with a rotating cylinder. The analysis shows that increasing forced circulation enhances the heat and mass transfer.
ENGINEERING RESEARCH EXPRESS
(2023)
Article
Mechanics
Leelasagar Koneti, K. Venkatasubbaiah
Summary: A comprehensive comparison of fluid flow and heat transfer characteristics inside a square enclosure with water or liquid gallium as fluids under natural convection has been studied numerically. The study found significant differences in the flow and heat transfer characteristics between conventional fluids like water and low Prandtl number fluids like liquid gallium. The diffusion mechanism is dominant in liquid gallium while convection is dominant in water. The heat transfer in liquid gallium is 25.61 times greater than in water at a Grashof number of 103. A correlation for average Nusselt number is developed for liquid gallium fluid in the range of Grashof number from 10(3) to 10(6).
INTERNATIONAL JOURNAL OF FLUID MECHANICS RESEARCH
(2023)
Article
Thermodynamics
M. S. Abhijith, K. Venkatasubbaiah
Summary: In this study, an in-house Fortran-based two-phase Eulerian-Eulerian solver is used to investigate an impinging jet in a minichannel using microencapsulated phase change material (MEPCM)-water slurry. The heat transfer performance of water-based n-eicosane and n-octadecane MEPCM slurries are examined, and the melting pattern of the particles within the minichannel is reported at various parameters. The research quantifies the heat transfer enhancement of the MEPCM-water slurry and identifies the optimal conditions for a water-based n-eicosane slurry at Re = 100 and epsilon(s) = 1%.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2022)
Article
Multidisciplinary Sciences
Naveen Janjanam, Rajesh Nimmagadda, Lazarus Godson Asirvatham, R. Harish, Somchai Wongwises
Summary: The study numerically analyzed the two-dimensional heat transfer performance of a stepped lid-driven cavity, considering Al2O3/water nanofluid with various nanoparticle concentrations. Simulations were conducted under different Reynolds and Grashof numbers, revealing that in certain cases, mixed convection shows better heat transfer performance than forced convection.
SN APPLIED SCIENCES
(2021)
Article
Thermodynamics
Veeresh Tekure, K. Venkatasubbaiah
Summary: The numerical investigation of supersonic turbulent non-reacting flow through a cavity-type flameholder in scramjet engines reveals the significant impact of subcavity types, aspect ratios, and locations on recirculation patterns and strengths.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2021)
Article
Thermodynamics
M. S. Abhijith, K. Venkatasubbaiah
Summary: The study shows that significant heat transfer enhancement is observed in MEPCM-water slurry compared to pure water as particles undergo melting. Furthermore, heat transfer enhancement increases with an increase in particle concentration. Using a combination of different phase change materials with varied melting temperatures can help maintain the melting of particles throughout the channel, leading to enhancement of heat transfer performance.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2021)
Article
Thermodynamics
M. S. Abhijith, K. Venkatasubbaiah
Summary: In this study, laminar forced convection of copper oxide and titanium oxide water-based nanofluid flow through a microchannel was numerically investigated. The results showed significant heat transfer enhancement with increasing Reynolds number and nanoparticle volume concentrations.
COMPUTATIONAL THERMAL SCIENCES
(2021)
Article
Thermodynamics
M. S. Abhijith, K. Venkatasubbaiah
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2020)
Article
Mechanics
Essam Nabil Ahmed, Alessandro Bottaro
Summary: This study focuses on the fully developed, steady, incompressible, laminar flow in a channel with rough and/or permeable walls. The influence of micro-structured boundary surfaces on the flow behavior is simulated using high-order effective boundary conditions derived from homogenization theory without empirical parameters. A closed-form solution of the Navier-Stokes equations is obtained for the flow in the channel, incorporating slip velocities, shear stress, and streamwise pressure gradient at each virtual boundary. The accuracy and applicability of the model are validated against full feature-resolving simulations for different textures. The Stokes-based model used to identify slip and interface permeability coefficients in the effective boundary conditions is reliable and accurate up to a certain threshold, beyond which advective effects need to be considered.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Mustafa Turkyilmazoglu, Faisal Z. Duraihem
Summary: Thermally-driven natural convection in a porous layer is explored theoretically in this work based on Darcy's law. The study focuses on the non-circulating basic cellular flow between two infinitely long horizontal plates and its instability onset. The results show that a circulatory flow and temperature variation along the horizontal axis govern the motion, and the instability can be determined through linear stability analysis and numerical calculations.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
P. Roca Ramis de Ayreflor, A. Viudez
Summary: In this study, the inelastic interactions between a small, intense dipole and a weak, neutral monopole in two-dimensional flows are examined. It is found that dipoles with small size but large amplitude can cross and scatter off the neutral vortex, while leaving the vortex stable.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Nilanjan Mondal, Chirodeep Bakli
Summary: This study presents a micro-nanochannel junction with directional flow achieved by a combination of junction geometry and wall functionalization. The system acts as a fluid diode with asymmetric pressure drop and flow rate in the nanochannel. The directional junction transport can be tuned with slip length, providing a key parameter for engineering various applications. The findings contribute to the understanding of flow rectification systems in nanochannels and have implications for capillary blood flow, desalination systems, and energy storage devices.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Ussama Ali, Anas Ghannam, Md Islam, Isam Janajreh
Summary: This study utilizes a passive flow control technique involving a slit through a circular structure to dampen flow-induced vibration. The results demonstrate that the presence of a slit can decrease lift and drag coefficients and suppress flow-induced vibration.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Sebastian A. Altmeyer
Summary: This article investigates how an alternating magnetic field can restrict and suppress the generation of vortices in ferrofluidic Couette flow. It finds that when the initially rotating outer cylinder is suddenly stopped, more complex vortex dynamics are generated in the system, and the presence of an alternating magnetic field can modify these dynamics, mainly depending on the modulation amplitude of the field.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Pradeep, L. P. Singh
Summary: This study focuses on the analytical solution to the Riemann problem for a 1-D non-ideal flow of dusty gas with external force. The elementary wave curves, including rarefaction wave, shock wave, and contact discontinuity, were obtained and their implications on density, velocity of flow, and shock speed were examined. The addition of external force results in non-self-similar solutions.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Meng Fan, Antoine Dazin, Gerard Bois, Francesco Romano
Summary: This study investigates the prominent features of the primary instabilities of a turbulent source flow between finite-span parallel rings with spatially modulated inflow conditions rotating at angular rate n. Two different two-dimensional instabilities that occur at large and low flow rates have been traced back to two different physical mechanisms related to jet-wake and mean-core flow, respectively. The effect of the radial aspect ratios on the instability characteristics of the flow between parallel rings is also considered.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Yasmin Hengster, Martin Lellep, Julian Weigel, Matthew Bross, Johannes Bosbach, Daniel Schanz, Andreas Schroder, Florian Huhn, Matteo Novara, Daniel Garaboa Paz, Christian J. Kahler, Moritz Linkmann
Summary: Using curvature and torsion to describe Lagrangian trajectories provides insights into small and large time scales. Probability density functions (PDFs) of curvature and torsion were calculated for experimental Lagrangian trajectories in different flows, and were compared with experimental and numerical simulation results. The effect of anisotropy on geometry or tracer particle trajectories was quantified using the curvature vector, which was found to be related to velocity fluctuations.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Nang X. Ho, Truong V. Vu
Summary: The present paper reports numerical results on the solidification process of a hollow drop on an inclined surface. The drop undergoes deformation and forms an asymmetric tip as the surface angle increases. The solidification time, however, is not affected by the surface angle. The fluid accumulates at the bottom of the drop and the bubble moves upwards before being trapped by solidification. A larger bubble reduces the tip shift. The effect of Bond number and Stefan number on solidification is also considered.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Idalia Jagodzinska, Bartosz Olszanski, Konrad Gumowski, Slawomir Kubacki
Summary: This study investigates the characteristics of high subsonic and transonic flows through a linear cascade using experimental investigations and numerical simulations. The experiments measured static pressure, flow field, and turbulent intensity, and provided inlet conditions for the numerical simulations. The simulations validated the experimental data and tested the applicability of the turbulence models.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Kun Sung Park, Ali Zamiri, Minsuk Choi, Byung Ju Lee, Jin Taek Chung
Summary: In this study, the stator geometry of a single-stage transonic fan was optimized to improve its aerodynamic performance and stall margin. Steady and unsteady simulations were conducted to analyze the impact of shock waves generated by the rotor blade on the stator inlet flow. Using a design of experiment and response surface method, an optimal geometry of the stator blade was obtained to increase the fan's efficiency and stall margin.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Yuanzhao Zhang, Bo Li
Summary: This study investigated the effects of longitudinal and lateral spacing on the aerodynamic drag characteristics of the whole team and each member in speed skating team pursuit competition. The results showed that decreasing the longitudinal spacing resulted in greater drag reduction for the whole team and individual skaters. Furthermore, lateral movement of the leading skater also led to additional drag reduction for the team. Computational fluid dynamics simulations revealed differences in drag distribution between the leading skater and the middle and last skaters.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Sichang Xu, Chris Peirone, Eugene Ryzer, Gary W. Rankin
Summary: This paper presents a study of a special bistable load-type supersonic fluidic oscillator capable of producing self-sustained oscillations in two gas pressure chambers. The experimental portion verifies the robust nature of the device performance and shows distinct differences compared to a similar prototype. A three-dimensional computational fluid dynamics model is required to accurately simulate the transient filling process, leading to an unaffordable computational cost. To address this issue, a low-order fluid circuit model is developed, which provides an accurate and rapid prediction of the transient performance.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
Article
Mechanics
Sampson Davis, Eli Shellabarger, James Miller, Thomas Ward
Summary: The present work focuses on studying the effects of shock wave - boundary layer interaction in 2D hypersonic flow at the sharp leading edge of a flat plate and a flat plate followed by a compression ramp. A key parameter, the hypersonic interaction parameter x, is defined and analyzed using a semi-analytic reduced-order model. The study aims to improve on existing methods by characterizing the viscous boundary layer and investigating the upstream influence resulting from the compression ramp.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2024)
