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Enhancement Evaluation Criteria for Pool Boiling Enhancement Structures in Electronics Cooling: CHF Enhancement Ratio (ER-CHF) and Enhancement Index (EI) J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-03-01 Maharshi Shukla, Satish Kandlikar
Extensive research shows the necessity of efficient cooling systems to enable electronic components to operate at high-performance levels for a sustained period. While conventional methods have served the cooling needs so far, rising computational power, energy efficiency, and sustainability requirements call for improved techniques. The literature shows the effectiveness of two-phase systems in cooling
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COLLISION MORPHOLOGIES OF SUPERCOOLED WATER DROPLETS ON SMALL LOW-TEMPERATURE SUPERHYDROPHOBIC SPHERICAL TARGETS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-02-01 Xin Liu, Yiqing Guo, Jingchun Min, Xuan ZHANG, Xiaomin Wu
The collision and freezing of supercooled water droplets exist in many fields and are usually unconducive. The superhydrophobic surfaces used for anti-icing generally have microstructures or local protrusions which could be simplified as small spherical targets comparable to the droplet in size. The supercooled water droplets' collision and freezing on small low-temperature superhydrophobic spherical
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Influence of transient heat pulse on heat transfer performance of vapor chamber with different filling ratios J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-02-01 Zhou Wang, Li Jia, Hongling Lu, Yutong Shen, Liaofei Yin
Due to the different application for portable electronic devices, there are instantaneous changes in the thermal load of the CPU and battery in the operation. The traditional uniform structure wick can not allow for evaporation and reflow of the working fluid under complex conditions, hence reducing the heat transfer performance of the vapor chamber (VC). This paper puts forward a novel style of VC
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Effect of Geometrical Parameters on the Thermal-Hydraulic Performance of Internal Helically Ribbed Tubes J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-02-01 Wentao Ji, Yi Du, Guo-Hui Ou, Pu-Hang Jin, Chuang-Yao Zhao, Ding-Cai Zhang, Wen-Quan Tao
The flow and heat transfer experiments are conducted in this paper for eleven internally grooved tubes. Refrigerants are boiling or condensing outside the tube. The experimental tubes have the internal helical rib heights of 0.25-0.36 mm, helix angles of 40-60°, rib base thicknesses of 0.40-0.79 mm, rib tip thicknesses of 0.078-0.283 mm, and Ns (Number of circumferential micro-fins per circle) of 40-50
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Condensation heat transfer in smooth and three-dimensional dimpled tubes of various materials J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-02-01 Wei Li
The heat transfer and pressure drop of R410A and R32 within a smooth and an enhanced dimpled tube were measured for mass fluxes from 100 kg m−2 s−1 to 400 kg m−2 s−1, average vapor qualities between 0.2 and 0.8, and saturation temperatures between 35℃ and 45℃.dimpled. The test section length was 2 meters, and the outer and inner diameters of the tubes were 9.52 and 8.32 mm, respectively. The inner
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Analysis of the Single-Blow Transient Testing Technique for Non-metallic Heat Exchangers J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-02-01 Wentao Li, Kun Sun, Guoyan ZHOU, Xing Luo, Shan-Tung Tu, Stephan Kabelac, Ke Wang
For measuring the efficiency of non-metallic heat exchangers, a mathematical model was established based on the principle of the single-blow testing technique, in which the conductive thermal resistance across non-metallic plates of the exchangers was taken into account. The analytical solution was obtained by means of the Laplace transformation and numerical invers transform method. The accuracy of
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Evaluation of Heat Transfer Rate of Double-Layered Heat Sink Cooling System with High Energy Dissipation J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-02-01 El Bachir Lahmer, Jaouad Benhamou, Youssef Admi, Mohammed Amine Moussaoui, Ahmed Mezrhab, Rakesh Kumar Phanden
The present work evaluates thermal exchange through a double-mini channel heat sink employed as a cooling system for electronic components. Different factors influencing heat exchange enhancement were investigated using Ansys-Fluent software, which enables the simulation of the fluid flow and heat transfer. The evaluation of thermal exchange between the cold fluid and heated solid with high thermal
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Experimental Investigation on Behavior of a Diesel Engine with Energy, Exergy, and Sustainability Analysis Using Titanium Oxide (Tio2) Blended Diesel and Biodiesel J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-02-01 AMAN SINGH RAJPOOT, TUSHAR Choudhary, ANOOP SHUKLA, H. CHELLADURAI, UPENDRA RAJAK, ABHINAV ANAND SINHA
The performance and emissions characteristics of a diesel engine running on several fuel combinations, including diesel, biodiesel, and fuel mixed with TiO2 nanoparticles, are assessed in this research on a diesel engine. The study investigates how performance and emissions are impacted when diesel and biodiesel are treated with 50 and 100 ppm of TiO2 nanoparticles under varied engine loads ranging
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POOL BOILING HEAT TRANSFER CHARACTERISTICS OF POROUS NICKEL MICROSTRUCTURE SURFACES J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Kun-Man Yao, Mou Xu, Shuo Yang, Xi-Zhe Huang, Dong-Chuan Mo, Shu-Shen Lyu
Pool boiling is an effective heat dissipation approach in electronic cooling, battery thermal management, etc. This study used the electrochemical deposition method to fabricate one smooth nickel specimen (named Ni-smooth) and three specimens with a porous nickel-stacked structure. The three porous specimens were created with deposition current densities of 0.5 A·cm-2 (named Ni-0.5), 2.0 A·cm-2 (names
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FIELD EXPERIMENTAL INVESTIGATION OF THE INSULATION DETERIORATION CHARACTERISTICS OF OVERHEAD PIPELINE FOR STEAM HEATING NETWORK J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Junguang Lin, Jianfa Zhao, Xiaotian Wang, Kailun Chen, Liang Zhang
The thermal insulation performance of pipeline is significant for the safety and economical operation of vapor steam network. In order to investigate the long-time insulation performance of pipeline, a field test was carried out in pipelines of 12 different heating networks with the operating time ranging from 1 to 11 years. Two different types of insulation coating layer were included. The total heat
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EXPERIMENTAL AND THEORETICAL CHARACTERIZATION OF TWO-PHASE FLOW DISTRIBUTION IN UNBALANCED FLOW NETWORKS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Cheol-Hwan Kim, Niccolo Giannetti, Nae-Hyun Kim, Kiyoshi Saito
This study investigates the two-phase flow distribution of R-1234yf into two-branched channels. The effect of unbalanced pressure drop and tube diameter on the flow distribution was especially characterized and modeled. The experiments were conducted for a mass flux ranging from 393 kg/m2s to 1179 kg/ m2s, and the inlet quality was fixed at 0.2. The flow distribution was mainly governed by the pressure
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FLOW AND HEAT-TRANSFER CHARACTERISTICS IN SMALL-DIAMETER TUBE BUNDLES WITH A STAGGERED LAYOUT: AN EXPERIMENTAL STUDY J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Han Qi, Guoqiang Xu, Weitong Liu, Lina Zhang, Yanchen Fu
While past research has primarily focused on heat transfer in larger diameter tubes, the capabilities of small-diameter tubes have often been estimated using correction factors. However, with the evolution of compact heat exchangers, conducting dedicated studies on small-diameter tube bundles has become increasingly crucial to achieve more precise conclusions. An experimental research on flow and heat-transfer
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A parametric and comparative study on bare-tube banks and new-cam-shaped tube banks for waste heat recovery applications J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Ngoctan Tran, Jane-Sunn Liaw, Chi-Chuan Wang
The present study numerically examines the effects of tube diameter (12 to 35 mm), arrangement, pitch-to-diameter ratio (1.25 to 2.5), length (300 to 1500 mm), and passage number (1-4 passes) on the thermofluidic characteristics of cross-flow tube bundles. Especially, five new cam-shaped tubes are proposed in comparison with the conventional round tube. The air temperatures at the cold and hot side
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ENHANCED FILM COOLING EFFECTIVENESS USING TURBULENCE PROMOTER IN COOLING HOLE J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 E. U. Martínez-Sandoval, Dulce M. Graciano, Fernando Zenaido Sierra-Espinosa, J. C. García
The film cooling is investigated experimentally and numerically for gas turbine blade cooling. Film cooling performance is vital for safe operation of the blades. By calculating the film cooling effectiveness, the effect of wall roughness through a turbulence promoter inside the cooling hole is evaluated. A turbulence promoter of aspect ratio K = L/h from 6 to 14, varying pitch L with constant height
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EXPLORING THE IMPACT OF MICROENCAPSULATED PHASE CHANGE MATERIALS ON HEAT TRANSFER PERFORMANCE IN AN OSCILLATING HEAT PIPE J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Max Noelker, Mark Owoola, Laith Ismael, Shahabeddin K. Mohammadian, Hongbin Ma
A comprehensive experimental study was performed on the influence of Microencapsulated Phase Change Materials (MPCMs) on the heat transfer performance in an oscillating heat pipe (OHP). The concept is based on the latent heat enhancement of MPCMs within the OHP: as the thermally excited oscillations propel MPCMs from the condenser to the evaporator, they undergo a phase change from solid to liquid
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USING A NONUNIFORM MAGNETIC FIELD TO ENHANCE HEAT TRANSFER BEFORE A SUDDEN COMPRESSION IN A 2D MILLI-CHANNEL J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Hamid-Reza Bahrami, Mahziyar Ghaedi
The advancement of electronic devices has made heat dissipation challenging, but heat convection shows promise as a solution. However, obstacles like resistors in the way of a straight channel can slow the flow and weaken heat transfer, particularly where the horizontal and vertical walls meet at sudden compression. This study examines numerically using nonuniform magnetic fields to enhance thermal
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MODELING AND SIMULATIONS OF WET POROUS MEDIUM CONVECTIVE DRYING J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Yicun Tang, Yuan Zhang, Jingchun Min
In the convective drying of a wet porous medium by hot air, the medium surface exposed to the air fluid may experience three stages, namely the fully wet, partly wet, and fully dry stages. At the fully wet stage, the medium surface is fully covered by a water film, with the convective moisture transfer taking place all over the medium surface; at the partly wet stage, the medium surface is partly covered
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HEAT TRANSFER ANALYSIS OF A COMBINED PIEZOELECTRIC FAN–TRANSLATIONAL AGITATOR COOLING SYSTEM J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Rutuja Bilaskar, Abhishek Singh, Sripriya Ramamoorthy, Shankar Krishnan
This paper investigates the heat transfer characteristics of a channel system consisting of a finned heat sink and two piezoelectric devices, the piezoelectric fan (PF) and the piezoelectric translational agitator (PTA), both experimentally and computationally. In the proposed system, the mean flow is generated by a cantilevered PF, and the flow between the fins is agitated using a PTA. A single-channel
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A COMBINED ACTIVE (PIEZOS) AND PASSIVE (MICROSTRUCTURING) PARTIAL FLOW-BOILING APPROACH FOR STABLE HIGH HEAT-FLUX COOLING WITH DIELECTRIC FLUIDS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Amitabh Narain, D. Pandya, J. Damsteegt, S. Loparo
Controlled but explosive growth in vaporization rates is made feasible by ultrasonic acoustothermal heating of the microlayers associated with microscale nucleating bubbles within the microstructured boiling surface/region of a millimeter-scale heat exchanger (HX). The HX is 5 cm long and has a 1 cm × 5 mm rectangular cross section that uses saturated partial flow-boiling operations of HFE-7000. Experiments
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THERMAL PERFORMANCE OF IONANOCOLLOIDS IN A CUBICAL CAVITY WITH INTERNAL PROTRUSIONS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 A. Hariharan, Rajan Harish
Ionic liquids have gained considerable attention as heat transfer fluids due to their unique properties, such as low vapor pressure and high thermal stability, which make them suitable for high-temperature applications. The purpose of this study is to examine the thermal behavior of ionanocolloids in a cubical cavity with an internal protruding heat source. The effect of Brownian motion and turbulence
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EXPERIMENTAL AND NUMERICAL STUDY ON SOLAR ENERGY STORAGE IN BLACK-COVERED SUNSPACE USING WATER-FILLED TIN CANS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Faraz Afshari, Emre Mandev, Burak Muratçobanoğlu, Ali Çelik, Mehmet Akif Ceviz
In this study, the aim was to store solar energy in a sunspace room for energy savings in cold regions by using water-filled tin cans. The energy collected in the water during the sunbathing hours is transferred to the environment in the evening when the ambient air temperature suddenly drops. Additionally, the walls were covered with black material in the sunspace area to absorb maximum solar energy
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ENERGY EFFICIENCY IMPROVEMENT AND ENTROPY GENERATION MINIMIZATION THROUGH STRUCTURAL OPTIMIZATION OF A DOUBLE-LAYER LIQUID-COOLED PLATE WITH CIRCULAR ARC-SHAPED FLOW CHANNELS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Gui-Kang Liu, Jing Wang, Yong-Qiang Chen, Shou-Yu Shi
Power batteries for new energy vehicles and other high-power electrical devices benefit greatly from liquid-cooled plates for thermal control. In the present work, a liquid-cooled plate with a double-layer arc-channel structure is developed to achieve a uniform temperature distribution on the surface of lithium-ion powered batteries and to reduce operating temperatures. Numerical simulations are employed
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DEVELOPMENT OF HEAT EXCHANGER WITH TWO-PASS DIVERGING MICROCHANNELS FOR EVAPORATION COOLING SYSTEMS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Kuan-Fu Sung, Cheng-Hung Hsu, Chien-Yuh Yang
This study developed a two-pass diverging microchannel heat exchanger to avoid flow reversal and partial dry out of HFC-245fa flow boiling in the evaporation cooling systems. It is aimed to improve the diverging microchannel heat exchangers designed by previous studies and to effectively accommodate diverging channels on a limited heating base surface. The test results showed that the maximum heat
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ENHANCING COOLING PERFORMANCE OF A HEAT EXCHANGER DRIVEN BY WATER/ALUMINA-SILICA HYBRID NANOFLUID: EXPERIMENTAL RESULTS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Sayantan Mukherjee, Sylwia Wciślik, Shikha Ebrahim, Purna Chandra Mishra, Naser Ali
The application of nanofluids in heat exchangers has been established to be beneficial in augmenting heat transfer performance. This study presents an experimental investigation of the performance of a heat exchanger using a water/Al2O3-SiO2 nanofluid under constant heat flux condition. The nanofluid, consisting of well-stabilized nanoparticles, was applied at concentrations ranging from 0.01 to 0
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INVESTIGATION OF THERMAL DISPERSION FOR STEADY AND PULSATING WATER FLOW IN METAL FOAM J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Altay Arbak, Nihad Dukhan
The dispersion coefficient in metal foam is critical for analysis and design using the volume-averaged equations. This coefficient is hardly investigated for steady flow, and has not been reported for non-steady flows in metal foam. This paper presents experimental and numerical investigations on the thermal dispersion coefficient in a metal-foam rectangular channel for steady and pulsating water flow
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INVESTIGATING THE PERFORMANCE OF A FLAT-PLATE SOLAR WATER-HEATING SYSTEM USING CeO2/WATER NANOFLUID: A HOLISTIC APPROACH J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Michael Joseph Stalin Prakasam, Palaniappan Murugesan, Manoj Kumar Pasupathi, Lokanadham Rapuru, Prabu Balaji, Vijayakumar Murugesan
The efficiency of a solar water heater with a flat-plate collector, which had an absorber area of 2 m2 and utilized a cerium oxide-water nanofluid as the working medium with a fixed volume fraction of 0.01%, was analyzed using a holistic approach. To assess the impact of flow rate on its heat transfer characteristics, the working fluid was systematically circulated through a pump-circulation system
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A COMPARATIVE STUDY OF CHANNEL COOLING ENHANCEMENT BY ANGLED, PARALLEL BROKEN, AND RHOMBUS PATTERNED RIBS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Jiangjiang Xing, Shaohua Han, Runsheng Zhang, Tianyi Huo, Yuanyuan Song, Na An, Leping Zhou, Li Li, Hui Zhang, Xiaoze Du
Heating and cooling of fluids play an important role in energy engineering, such as solar air heaters and the internal cooling of gas turbine blades. Heat transfer in the heat exchanger channels can be enhanced by ribs, which will also result in a significant decrease in coolant pressure. In our previous work, a novel bioinspired rib design with a rhombus-shaped pattern was proposed to enhance the
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HEAT TRANSFER IN A FORM-STABLE DIRECT-CONTACT LATENT THERMAL ENERGY STORAGE UNIT J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 N. S. Susan Mousavi, M. Tashfeen Syed, Prabodh Panindre, Sunil Kumar
This study investigated various aspects of thermal storage concept, including material characterization and analysis of form-stable, unencapsulated phase-change materials (PCM) that underwent solid-solid phase transition and was in direct contact with the working fluid. The study focused on temperature range between 100−140°C (212−284°F). Mathematical heat transfer models were developed to examine
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PERFORMANCE IMPROVEMENT OF CIRCULAR PARABOLIC CONCENTRATING SOLAR COOKER USING NANO-MIXED BINARY SALT PHASE CHANGE MATERIAL J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2024-01-01 Chetan Papade, Amarsingh B. Kanase-Patil
A multi-objective investigation has been carried out for a parabolic concentrator-type solar cooker with the use of nano-mixed binary salts phase change material (PCM) materials. Binary salts like NaNO3 and KNO3 are mixed with alumina (Al2O3) nanoparticles in the ratio of 0.5%, 1%, and 1.5% by weight. Properties such as thermal conductivity, specific heat, melting point, and thermal diffusivity are
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Revving up heat transfer performance of double pipe heat exchanger using diverse molar Ag-GO hybrid nanofluids: An Empirical and Numerical study using Central Composite Design J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-08-01 Armstrong M, Sivasubramanian M, Selvapalam N, Rajaganapathy C
This study seamlessly integrates empirical and numerical approaches to enhance the efficiency of a double pipe heat exchanger (DPHX) using varied molar concentrations (0.03M, 0.06M, and 0.09M) of Ag doped GO hybrid nanofluids as the working fluids within the heat exchanger's annulus. Remarkable improvements in the heat exchanger's performance were achieved by increasing the molar concentration of Ag-GO
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Numerical study on flow and heat transfer and performance of a novel multi-layer mini-channel heat exchanger with low axial heat conduction J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-06-01 Libo Li, Jiyuan Bi, Xiaoxu Zhang, Bo Yang, Qiuwang Wang, Ting Ma
Mini-channel heat exchanger is generally applied for many advanced energy and power systems because it has very high compactness and high efficiency. Nevertheless, axial heat conduction may remarkably decrease the efficiency at low mass flow rates. This study proposed a novel multi-layer mini-channel heat exchanger to solve this problem. The axial heat conduction of the new design is reduced by inserting
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Heatfunction Analytics of Conjugate Natural Convection Heat Transfer in Partitioned Enclosure Filled with Hybrid Nanofluid Under Magnetic Fields J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-05-01 Mufutau Waheed, Christopher Enweremadu
The need for suitable control of fluid flow and heat transfer for an enhanced performance has led to the use of magnetic field, appropriate design and sizing of the device and the right choice of the flow governing parameters for many industrial processes. This study investigates the effects of uniform magnetic field on the heat flow induced by buoyancy in a square enclosure partitioned into two cavities
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Prediction of Heat Transport and Drag Force of Ferrofluids around a Sphere in the Presence of Oscillating Magnetic Field J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-03-01 Zeinab Abbasi, Asghar Dehkordi
In this article, the heat transfer of magnetic nanofluids over a sphere has been considered in the presence of an external oscillating uniform magnetic field for various range of Reynolds number (Re). The significant difference between the magnetic property of the nanofluid and the heated sphere makes a non-uniform magnetic field around the sphere resulting a significant alteration in the distribution
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THE INFLUENCE OF NATURAL CONVECTION ON EFFECTIVE THERMAL CONDUCTIVITY OF ANISOTROPIC OPEN-CELL FOAM J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Chao Zhang, Hui Wang, Yanxia Du, Xian Wang, Guangming Xiao
Accurately predicting the effective thermal conductivity (ETC) of anisotropic open-cell foam when natural convection effects are present is a significant challenge. In this work, a comprehensive process was built to predict ETC of anisotropic open-cell foam reconstructed using X-ray computed tomography considering natural convection effects at pore scale. The hybrid thermal lattice Boltzmann method
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EXPERIMENTAL INVESTIGATION AND LIFE-CYCLE COST ANALYSIS OF A MULTI-PIPE ARRAY HEAT STORAGE SYSTEM USING PHASE-CHANGE MATERIALS FOR SOLAR GREENHOUSE HEATING J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Chong Zhang, Qiang Yang, Luwei Yang, Juan Wei, Xiaoxi Gou, Zhichao Wang
To simplify the structure of accumulator and enhance the utilization of phase-change materials (PCM), this paper presents the development, experimental investigation, and life-cycle cost of a novel phase-change heat storage system with multi-pipe array type for greenhouse heating. The platforms of single accumulator performance evaluation and multi-pipe array storage system performance evaluation were
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PREFACE: ADVANCED THERMAL MANAGEMENT, ENERGY CONVERSION, AND STORAGE TECHNOLOGIES J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Lixin Cheng, Guodong Xia, Zhixiong Guo
N/A
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RECENT PROGRESS ON HEAT TRANSFER PERFORMANCE AND INFLUENCING FACTORS OF DIFFERENT MICROCHANNEL HEAT SINKS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Xiaojun Xiong, Yifan Li, Chenggong Zhao, Wei Yu
The microchannel heat sink (MCHS) is an efficient thermal management technology widely used in various fields, including electronic equipment, automobiles, and aerospace. In this paper, the recent advances in cross-sectional shape, coolant type, flow channel shape, flow pattern, and application scenarios of the MCHS are systematically reviewed. The liquid film thickness in circular microchannels is
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EFFECT OF WAVY TUBE STRUCTURE ON THE COMPREHENSIVE PERFORMANCE OF SUPERCRITICAL CARBON DIOXIDE AND LEAD BISMUTH EUTECTIC COMPACT HEAT EXCHANGER J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Liu Shuhan, Liu Qingjiang, Liu Ji'an, Lei Xianliang
In the combined system of lead-cooled fast reactor and supercritical carbon dioxide (S-CO2) Brayton cycle, the intermediate heat exchanger plays a key role in the whole power system. However, the existing heat exchanger cannot meet the trend of miniaturization of lead-cooled fast reactors. Considering the thermo-physical properties and heat transfer behaviors in both S-CO2 and liquid lead bismuth eutectic
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SIMULATION OF THE COLD-END TEMPERATURE AND THE OPTIMAL CURRENT OF THERMOELECTRIC COOLER WITH VARIABLE SEMICONDUCTOR CROSS SECTION USING LATTICE BOLTZMANN METHOD J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Jimin Xu, Tianwang Lai, Xiangyang Liu, Maogang He
In order to evaluate the effects of variable semiconductor cross section on the cold-end temperature of thermoelectric cooler (TEC), the numerical model of the cold-end temperature field of TEC with variable semiconductor cross section was established using the lattice Boltzmann method (LBM) in this work, Firstly, the Chapman−Enskog expansion method was used to derive the LBM model and build the parameter
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PERFORMANCE OPTIMIZATION OF SUPERCRITICAL CO2 GAS HEATER IN A BIOMASS-CO2 POWER GENERATION SYSTEM J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 X. Zhang, Yunting Ge
A comprehensive computational fluid dynamics (CFD) simulation model was developed in the current research to simulate a shell-and-tube supercritical CO2 gas heater used in a biomass-CO2 power generation system. The model was based on the actual design of the heat exchanger and relevant operational parameters. The simulation model was validated using manufacturer operational data and empirical correlations
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PARAMETRIC STUDY OF AGITATOR IN TiO2 PRECIPITATION TANK USING MULTIPHASE COMPUTATIONAL FLUID DYNAMICS SIMULATION AND EXPERIMENTS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Junhee Han, Hyojung Kim, Dohyung Lee
The production of high-quality white pigment in the sulfate process heavily relies on the formation of titanium dioxide particles of anatase. Uniformity of the TiO2 particle is a crucial factor in determining the quality of the final products, which can be improved by maximizing the mixing rate in the precipitation tank. This uniformity is also essential to the efficiency of the subsequent Moore filtration
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INVESTIGATION ON THE EFFECT OF OSCILLATING MAGNETIC FIELDS ON FLUID FLOW AND FORCED-CONVECTION HEAT TRANSFER AROUND A SPHERE J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Zeinab Abbasi, Asghar Molaei Dehkordi
In this article, the heat transfer of magnetic nanofluids over a sphere has been considered in the presence of an external oscillating uniform magnetic field for a wide range of Reynolds number values (Re). This study incorporates the effect of magnetic permeability and purposes the optimal operating condition for the first time. The significant difference between the magnetic property of the nanofluid
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EXPERIMENTAL INVESTIGATIONS FOR EFFECTIVENESS OF COMBINED IMPINGEMENT FILM COOLING J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Rajesh Kumar Panda, Arun Kumar Pujari, Babji Gudla
Protecting the gas turbine blades from high-temperature gases and increasing the specific work output is one of the most challenging tasks for most gas turbine design engineers. Combined impingement and film cooling can be used as a hybrid cooling technology to improve the film cooling performance over the gas turbine blade surfaces. In the present work, experimentations were performed on a flat plate
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THERMAL MANAGEMENT STRATEGY WITH PHASE-CHANGE MATERIAL CAPSULES FOR PULSED-POWER SOURCE CONTROLLER IN EXTREME OIL-WELL THERMAL ENVIRONMENT J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Junjie He, Shihong Ma, Qiuwang Wang, Wenxiao Chu
The application of a pulsed-power source controller provides high energy and strong penetrability, which can effectively improve the shale oil exploitation efficiency. However, the harsh high-temperature oil-well environment will significantly affect the safe operation of electronic devices. This study compares the thermal protection performance of the insulation layer with microscale phase-change
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HEAT TRANSFER ENHANCEMENT IN A CHANNEL WITH INCLINED BAFFLES UNDER PULSATING FLOW: A CFD STUDY J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Selma Akcay, Unal Akdag
This study numerically investigated hydraulic and thermal performance in a channel with inclined baffles under pulsating flow conditions. The baffles were placed in a staggered arrangement. The governing equations were discretized with the finite volume method (FVM), and the pressure-velocity coupling was handled by the SIMPLE algorithm. The Strouhal number (St: 0.5,1, 2, 3, and 4), pulsation amplitude
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SENSITIVITY ANALYSIS AND OPTIMIZATION OF WAVY FIN CIRCULAR TUBE HEAT EXCHANGER J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Monoj Bardalai, Uday Aditya Boruah
The present study shows the strong ability of a genetic algorithm (GA) in the thermal design and optimization of a herringbone wavy fin and circular tube compact heat exchanger (FTHE). The influences of various design parameters on friction factor, Colburn factor, and minimum total annual cost (TAC) are presented. Mainly, three design objectives are considered, such as minimum friction factor, maximum
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EXPERIMENTAL INVESTIGATION OF FLOW BOILING PARAMETERS IN A TRANSVERSE GROOVED HORIZONTAL TUBE: CRITICAL HEAT FLUX, PRESSURE DROP, AND HEAT TRANSFER COEFFICIENT J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 P. N. Tank, Arunkumar Sridharan, S. V. Prabhu
An experimental investigation was conducted to examine critical heat flux (CHF), boiling pressure drop, and local heat transfer coefficient in a horizontal channel with transverse grooves for flow boiling with R-123. Measurement of the wall temperature of the channel was done using a thermal camera. Five test sections were used for the study. A combination of groove pitch (p) of 18.6 and 11 mm and
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EXPERIMENTAL INVESTIGATION OF HEAT TRANSFER AND PRESSURE DROP CHARACTERISTICS FOR VERTICAL DOWNFLOW USING TRADITIONAL AND 3D-PRINTED MINI TUBES J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Jia Hang Chen, Yi Fan Yang, Lam Lam, Min Zeng, Ting Ma, Lap Mou Tam, Afshin J. Ghajar
In this study, an investigation on the influences of different manufacturing techniques on the heat transfer and pressure drop in the developing and fully developed regions of mini-tube under different flow regimes is introduced. The purpose of this research is to experimentally investigate the heat transfer and pressure drop characteristics using 3D-printed tubes and traditional stainless steel tubes
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EXPERIMENTAL STUDY ON THE HEAT TRANSFER CHARACTERISTICS OF SUPERCRITICAL CARBON DIOXIDE IN THE STRAIGHTLY-RIBBED TUBES J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Yusheng Li, Xianliang Lei, Yahui Wang
The supercritical carbon dioxide (S-CO2) Brayton cycle shows great advantages in structural compactness and thermal efficiency. To ensure the safety of the heating surface under high load, the flow and heat transfer characteristics in straightly-ribbed tubes is studied to explore the improvement on the convective heat transfer ability of S-CO2 and inhibition on the deteriorated heat transfer. An experimental
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A TREE-SHAPED LAYOUT HEAT PIPE TO ENHANCE HEAT TRANSFER IN A PHASE-CHANGE MATERIAL STORAGE PROCESS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Binxu Gao, Shuli Liu, Abdur Rehman Mazhar, Yongliang Shen, Tingsen Chen, Shaoliang Zhang
Phase-change materials (PCMs) are promising in energy storage. However, the low thermal conductivity of a PCM limits its practical application. A tree-shaped layout heat pipe has been studied in this paper to improve the heat transfer performance in PCM energy storage. Based on the thermal imaging picture distribution of conventional heat pipes within the PCM during the heat storage process, tree-shaped
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INVESTIGATION ON DROPLET EVAPORATION CONSIDERING RADIATION HEAT TRANSFER BY A DEVELOPED LATTICE BOLTZMANN MODEL J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Haoran Hong, Xiaojing Ma, Jinliang Xu, Yong Ren
Suspended droplet evaporation in high temperature is common seen and widely used in various industries. Different from the previous lattice Boltzmann model of liquid-vapor phase change, a newly developed model which can consider radiation heat transfer is proposed and used to simulate the suspended droplet evaporation process. This model is verified by the theoretical solutions and compared with the
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MOLECULAR STUDY OF CORE-SHELL RATIO EFFECT ON THERMOPHYSICAL PROPERTIES OF SIO2@AU-WATER NANOFLUID J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Saad F. M. Noraldeen, Jin Lu, Leping Zhou
Thermal conductivity (λ) and specific heat capacity (cp) are essential thermophysical properties related to thermal storage systems. Molecular simulations of the shell-to-total-radius ratios (Φ) of SiO2@ Au nanoparticle (NP) are used to investigate their impact on the cp and λ of water nanofluids (NFs) containing this NP. The roles of solid/liquid and solid/solid interfaces on cp and λ are identified
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IN CELEBRATION OF PROFESSOR JOHN RICHARD THOME ON HIS 70TH BIRTHDAY J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Lixin Cheng, Bofeng Bai, Guodong Xia, Hai-Bin Zhang, Zhixiong Guo
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NUMERICAL INVESTIGATION ON HEAT TRANSFER OF SUPERCRITICAL PRESSURE CO2 IN A BENT PIPE J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Haoyang Liu, Zhenlong Fang, Deng Li, Qiang Wu, Zhimin Yao, Zenglei Zhang, Ruichao Shi
The flow characteristics and heat transfer mechanism of supercritical pressure CO2 in a bent pipe were studied by the method of numerical simulation. The velocity, temperature, secondary flow, and turbulent kinetic energy distribution of the CO2 under different heating conditions are analyzed. The effects of pipe bend and sharp changes in the thermal properties of CO2 on the flow field and temperature
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ANALYSIS OF PLATE-FIN HEAT SINK INFUSED WITH PHASE CHANGE MATERIALS FOR INTERMITTENT SPACE MISSIONS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Mohammed Azzam, Mohammad O. Hamdan, Maen Alkhader, Frank M. Gerner
In this work, we numerically investigated the heat transfer effectiveness of different phase change materials (PCMs) when infused in a plate-fin heat sink with a fixed volume fraction of thermal conductivity enhancer. The PCM's ability to absorb and release large amounts of thermal energy at constant temperature is a desired feature in transient electronics cooling applications. In this study, we focused
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HEAT-TRANSFER ENHANCEMENT OF MONO ETHYLENE GLYCOL−WATER-BASED SOLAR THERMIC FLUIDS DISPERSED WITH MULTIWALLED CARBON NANOTUBES IN A COILED TUBE HEAT EXCHANGER J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Srinivas Vadapalli, Jai Kumar Sagari, Haricharan Alapati, Vishnuvardhan Reddy Kalamalla, Ravi Su
The current research focuses on how the inclusion of multiwalled carbon nanotubes (MWCNTs) in mono ethylene glycol-water mixtures affects thermal conductivity, heat transfer, and dynamic viscosity for solar thermal applications. To achieve high stability in mono ethylene glycol-water mixtures, MWCNTs were oxidized and then dispersed at concentrations of 0.5, 0.25, and 0.125 wt.%. Zeta potential analysis
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CONDENSATION HEAT-TRANSFER ENHANCEMENT USING STEAM-ETHANOL MIXTURES ON A HORIZONTAL BANK OF TUBES J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Hassan Ali, Sajid Kamran, Farukh Farukh, Wajid Saleem, Samna Batool, Saqib Jivani
Significant heat-transfer enhancement using steam-ethanol mixtures can be obtained as compared to that of pure steam. Due to addition of small concentrations of ethanol, the condensate mode resembles that of typical dropwise condensation on a hydrophobic surface. Surface tension instabilities, also known as Marangoni phenomenon, take place when small amounts of ethanol are added to pure steam. It has
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HEAT-TRANSFER ENHANCEMENT OF A SOLAR PARABOLIC TROUGH COLLECTOR USING TURBULATORS AND NANOPARTICLES: A NUMERICAL STUDY J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Usman Allauddin, Muhammad Ikhlaq, Tariq Jamil, Fahad Alvi, Hibtullah A. Hussain, Hussain Mustafa, Muhammad Hassan Azeem
Solar energy harnessing devices exhibit promising potential for providing a significant portion of the energy requirement. Among these devices, the solar parabolic trough collector (PTC) is a well-renowned and effective technology. In recent times, a great deal of research has been done further improving the thermal performance of PTC systems. The current numerical study investigates the effect of
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PERFORMANCE ANALYSIS OF THERMO-ELECTRIC COOLING SYSTEMS EQUIPPED WITH SURFACE-MODIFIED AND RECYCLED NANOFLUIDS J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Emre Mandev, Burak Muratçobanoglu, Eyüphan Manay, Bayram Sahin, Reza Teimuri-Mofrad, Shabnam Rahimpour, Faraz Afshari
In this research, pure water and recycled nanofluids (RNF) are utilized as heat transfer fluids in the thermoelectric cooling (TEC) system, and the effects of these fluids on the cooling performance are experimentally examined. In order to prevent nanofluid sedimentation and enhance stability, a surface modification process on Fe3O4 particles is performed. With modified Fe3O4@SiO2-mix-(CH2)3Cl@Imidazol
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SELF-ASSEMBLED SYNTHESIS OF MICROENCAPSULATED PARAFFIN WAX PHASE CHANGE MATERIALS WITH EXCELLENT THERMAL PROPERTIES OF CALCIUM CARBONATE SHELL J. Enhanc. Heat Transf. (IF 2.3) Pub Date : 2023-01-01 Xinyi Liu, Jifen Wang, Huaqing Xie, Zhixiong Guo
The PW@CaCO3 phase change microcapsule composites with paraffin wax (PW) as core and calcium carbonate (CaCO3) as shell were successfully prepared by the self-assembly method. During the preparation process, different core-to-wall ratios and different temperatures affected the morphology, encapsulation rate, thermal stability, and thermal conductivity of the microcapsules. Eight sets of microcapsule