Abeer H. Falih^*, Basima Salman Khalaf, Basim Freegah

Frontiers in Heat and Mass Transfer, Vol.22, No.2, pp. 597-613, 2024, DOI:10.32604/fhmt.2024.049812

Abstract In this study, the primary objective was to enhance the hydrothermal performance of a dimpled tube by addressing areas with low heat transfer compared to other regions. To accomplish this, a comprehensive numerical investigation was conducted using ANSYS Fluent 2022 R1 software, focusing on different diameters of dimples along the pipe’s length and the distribution of dimples in both in-line and staggered arrangements. The simulations utilized the finite element method to address turbulent flow within the tube by solving partial differential equations, encompassing Re numbers spanning from 3000 to 8000. The study specifically examined single-phase… More > Graphic Abstract

Liqun Zhou^1,*, Weilin Yang¹, Chaojie Li², Shi Lin³

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 157-173, 2024, DOI:10.32604/fhmt.2023.045135

Abstract The power density of electronic components grows continuously, and the subsequent heat accumulation and temperature increase inevitably affect electronic equipment’s stability, reliability and service life. Therefore, achieving efficient cooling in limited space has become a key problem in updating electronic devices with high performance and high integration. Two-phase immersion is a novel cooling method. The computational fluid dynamics (CFD) method is used to investigate the cooling performance of two-phase immersion cooling on high-power electronics. The two-dimensional CFD model is utilized by the volume of fluid (VOF) method and Reynolds Stress Model. Lee’s model was employed… More > Graphic Abstract

A. Valan Arasu^a,*, Agus P. Sasmito^b,†, Arun S. Mujumdar^b

Frontiers in Heat and Mass Transfer, Vol.2, No.4, pp. 1-7, 2011, DOI:10.5098/hmt.v2.4.3005

Abstract The heat transfer enhancement of paraffin wax, a cheap and widely used latent heat thermal energy storage material, using nanoparticles is investigated. The effects of nanoparticle volume fraction on both the melting and solidification rates of paraffin wax are analysed and compared for Al₂O₃ and CuO nanoparticles. Present results show that dispersing nanoparticles in smaller volumetric fractions increase the heat transfer rate. The enhancement in thermal performance of paraffin wax is greater for Al₂O₃ compared with that for CuO nanoparticles. More >

Tao Wang¹, Zhen Tian¹, Chen Gao¹, Quanfu Gao¹, Kewei Song^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-3, 2023, DOI:10.32604/icces.2023.8880

Abstract With the rapid development of the economy and the increasing consumption of fossil energy, energysaving becomes imperative [1,2]. Improving the heat transfer efficiency of heat exchangers, which are widely applied in many fields, is important for energy utilization [3,4]. Twisted tube can produce secondary flow, increase turbulence and thin thermal boundary layer, and hence the enhancement of heat transfer [5-9]. However, the mixture of the fluid between the center of the twisted tube and the region around the tube is still not effectively improved. Thus, the heat transfer of the twisted tube can be further… More >

Anand Shukla^a, Alok Chaube^b, Shailesh Guptac^†, Arvind Sirsath^c

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-8, 2014, DOI:10.5098/hmt.5.14

Abstract One of the traditional methods used to improve the efficiency of a gas turbine is to increases the inlet temperature; thereby increasing the power output and in turn, the efficiency. The internal cooling passages of blades are roughened by artificial roughness to improve the cooling performance. The present study investigates the convective heat transfer and friction factor (pressure drop) characteristics of a rib-roughened square duct. The test section of the duct is roughened on its top and bottom wall with V and ᴧ- shaped square ribs. In the study, the Reynolds number (Re) varied from 10,000… More >

Amnart Boonloi^*

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-12, 2014, DOI:10.5098/hmt.5.8

Abstract A mathematical analysis of the heat transfer enhancement, thermal performance and flow configurations in a heat exchanger square duct with diagonal inserted plate vortex generators is presented. The 30o V–shaped baffles are modified and placed on the double sides of the thin plate or frame (with no plate) which inserted diagonally in the square duct. The effects of blockage ratio (b/H, BR), the pitch ratio (p/H, PR), flow direction (V–Downstream and V–Upstream) and configuration of inserting plate are investigated for Reynolds number based on the hydraulic diameter of the square duct, D_h, Re = 100 –… More >

Ayad S. Abedalh^*, Sohaib Hassan Mohammed

Frontiers in Heat and Mass Transfer, Vol.21, pp. 227-243, 2023, DOI:10.32604/fhmt.2023.041777

Abstract Solar energy, a renewable resource, can be harnessed instead of fossil fuels to generate power and heat. One effective method for converting solar energy into heat is through a solar air heating (SAH) system. The theoretical investigation focused on the thermal performance of various V-groove angles on a corrugated absorber plate. The researchers maintained the exterior dimensions and constraints of the absorber plate while increasing its surface area by using a corrugated absorber surface. For the simulation, three different V-groove angles were employed: 45°, 30°, and 15°. The temperature and air flow rate into the… More > Graphic Abstract

Amnart Boonloi¹, Withada Jedsadaratanachai^2,*

Frontiers in Heat and Mass Transfer, Vol.21, pp. 81-106, 2023, DOI:10.32604/fhmt.2023.041547

Abstract Simulation of fluid-flow topology and thermal behavior in a round tube heat exchanger (RTHX) installed by three V-rib sets is reported. The expected phenomena for the rib installation are the generated vortex flow, impinging flow, greater fluid blending and thermal boundary layer disturbance (TBLD). These phenomena are key causes of the augmentation of heat transfer potentiality and thermal efficiency of the RTHX. Effects of rib height (b₁ = 0.05D – 0.25D and b₂ = 0.05D – 0.25D), rib pitch or rib spacing (P = D, 1.5D and 2D) and fluid directions (positive x (+x flow direction)… More > Graphic Abstract

Amnart Boonloi^a, Withada Jedsadaratanachai^b,*

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-16, 2016, DOI:10.5098/hmt.7.22

Abstract The numerical investigations on flow structure, heat transfer characteristic and thermal performance in a circular tube heat exchanger with various shapes of winglet vortex generators are reported. The rectangular winglet vortex generators (RWVG), delta winglet vortex generators (DWVG) and curve winglet vortex generators (CWVG) are inserted in the middle of the test tube on both downstream and upstream arrangements. The effects of blockage ratios; BR = 0.1 – 0.3, with single pitch ratio (PR = 1) and flow attack angle (α = 30o) on thermal performance are studied for the Reynolds numbers; Re = 100 – 2000. The… More >

Withada Jedsadaratanachai^a, Amnart Boonloi^b,*

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-8, 2017, DOI:10.5098/hmt.8.35

Abstract Numerical investigations on flow and heat transfer characteristics in a circular tube heat exchanger inserted with right triangular wavy surfaces are reported. The configurations of the wavy surfaces; incline and V-shape, are studied with flow attack angles of 30o, 45o and 60o for the Reynolds numbers, Re = 100 – 2000. The numerical results are compared with the smooth circular tube. The mechanisms on flow and heat transfer in the tube heat exchanger with the wavy surface are presented. As the results, the wavy surface can generate the vortex flow and impinging flow through the test… More >