Maryam Mirzaie^a,† , Ali Reza Talebizadeh^a , Hassan Hashemipour^a,b

Frontiers in Heat and Mass Transfer, Vol.14, No.1, pp. 1-7, 2020, DOI:10.5098/hmt.14.19

Abstract In this work, a combination of computational fluid dynamics (CFD) and porous media model was applied to simulate the benzene adsorption on activated carbon and the flow fields in a porous media. The three dimensional unsteady state the gas flow was modeled by using the laminar one phase flow equations in conjunction with the mass transfer equation. The adsorption rate on solid phase was implemented to the model by a user defined source. The model was validated by comparing the simulated breakthrough curves by experimental data. After the validation of the model, the effects of the operating conditions such as… More >

Jing Hu^a,* , Mingxing Du^b

Frontiers in Heat and Mass Transfer, Vol.14, No.1, pp. 1-7, 2020, DOI:10.5098/hmt.14.5

Abstract Inert gases are conveniently used for leak detection. Relative to CO₂, majority of the inert gases are non-condensable. It is of great significance to understand the effects of residual non-condensable gases on the performance of a refrigeration system. This paper investigates, both theoretically and experimentally, on the impact of residual non-condensable gases on the performance of a carbon dioxide (CO₂) evaporator and the system performance. A theoretical analysis indicates that residual non-condensable gases can convert homogeneous nucleation into a heterogeneous nucleation process and accelerate phase change, thus, reducing superheat or incipient boiling temperature. To investigate the influence of residual non-condensable… More >

S. Ravi Teja^a , Chellapilla V. K. N. S. N. Moorthy^b,*, S. Jayakumar^c , Ayyagari Kiran Kumar^d , V. Srinivas^c,*

Frontiers in Heat and Mass Transfer, Vol.15, No.1, pp. 1-9, 2020, DOI:10.5098/hmt.15.7

Abstract This article is a summary of research involving the evaluation of the thermo-physical properties of Mono-ethylene - glycol-based solar thermic fluids oxidized multiwalled carbon nanotubes. Nanofluids were prepared with Mono-ethylene glycol and water as base fluids in 100:0, 90:10 and 80:20 ratios. These base fluids of three categories were dispersed with purified and oxidized multiwalled carbon nanotubes (MWCNTs) in the weight fractions of 0.125, 0.25 and 0.5 percentages. The variation in zeta potential is studied to examine the dispersion stability during 2 months. Thermal conductivity and dynamic viscosity were measured by hot disk method and Anton paar viscometer respectively. Significant… More >

Zhiyong Yang¹, Jiacheng Zhang¹, Henglin Xiao^1,2, Zhi Chen^1,*, Tian Bao¹, Yin Liu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2267-2288, 2023, DOI:10.32604/fdmp.2023.028652

Abstract The use of carbon-fiber heating cables (CFHC) to achieve effective melting of snow and ice deposited on roads is a method used worldwide. In this study, tensile and compressive tests have been conducted to analyze the mechanical properties of the CFHC and assess whether the maximum tensile and compressive strengths can meet the pavement design specifications. In order to study the aging produced by multiple cycles of heating and cooling, in particular, the CFHC was repeatedly heated in a cold chamber with an ambient temperature ranging between −20°C and +40°C. Moreover, to evaluate how the strength of the pavement is… More > Graphic Abstract

Jinlong Shang^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2315-2328, 2023, DOI:10.32604/fdmp.2023.026742

Abstract In this study, the durability of a new polymer carbon fiber-reinforced epoxy resin used to produce composite material in the aerospace field is investigated through analysis of the corrosion phenomena occurring at the microscopic scale, and the related infrared spectra and thermal properties. It is found that light and heat can contribute to the aging process. In particular, the longitudinal tensile strength displays a non-monotonic trend, i.e., it first increases and then decreases over time. By contrast, the longitudinal compressive and inter-laminar shear strengths do not show significant changes. It is also shown that the inter-laminar shear strength of carbon… More >

Rongge Xiao^a,*, Shuaishuai Jin^a, Xin Feng^b, Peng Zhang^c, Zheng Dai^c

Frontiers in Heat and Mass Transfer, Vol.16, No.1, pp. 1-7, 2021, DOI:10.5098/hmt.16.25

Abstract With the increasing production and use of natural gas, the supersonic nozzle has become focus of the impurity removal research. In this paper, the modified classical nucleation model is used as the condensation nucleation model, and the Gyarmathy growth model is selected as the droplet growth model. Based on the assumption of no phase slip and Eulerian two fluid model, the flow control equation of wet natural gas is established. By giving the selection criteria as a turbulence equation, the SRK real gas equation is used to carry out the corresponding numerical simulation. The required supersonic nozzle structure and grid… More >

Kapil Dev Choudhary, Shyam Sunder Yadav^† , Mani Sankar Dasgupta

Frontiers in Heat and Mass Transfer, Vol.16, No.1, pp. 1-10, 2021, DOI:10.5098/hmt.16.14

Abstract In the current work, we simulate the condensation of supercritical CO₂ during its high speed flow inside two different converging-diverging nozzles. We use the homogeneous equilibrium method and the classical nucleation theory based non-equilibrium phase change model for this purpose. The simulation results indicate significant influence of the nozzle inlet condition, nozzle shape and the fluid thermophysical behaviour on the nonequilibrium conditions prevailing inside the nozzles. We observe very low, ∼0.15 K, supercooling for the flow of CO₂ inside the Claudio Lettieri nozzle compared to the supercooling of ∼3 K observed for the Berana nozzle. Very high nucleation rate (∼… More >

P.S.S. Nagalakshmi, N. Vijaya^*

Frontiers in Heat and Mass Transfer, Vol.19, No.1, pp. 1-18, 2022, DOI:10.5098/hmt.19.17

Abstract The main emphasis of this study is to examine the entropy generation of the spatial-temporal state of Bingham visco-plastic nanofluid flow between parallel plates are solved numerically using adequate similarity solutions. Python with BVP solver is used to interpret the results of the adopted model. Heat and mass transfer rate with respect to yield stress was investigated. The results report that the entopy generation of nanofluids exploring single and multiwalled carbon nanotubes dims with the increasing local thermal Peclet number nearer the lower and upper plates. Researchers have established that entropy generation can be reduced by increasing Fourier’s number (Fe)… More >

Tieming Wang^a , Fuyong Su^b,*

Frontiers in Heat and Mass Transfer, Vol.20, No.1, pp. 1-4, 2023, DOI:10.5098/hmt.20.12

Abstract This paper analyzes the power generation technology of coke dry quenching (CDQ) waste heat boiler, and compares the exergy efficiency of medium temperature medium pressure boiler and high temperature high pressure boiler. The scheme of high temperature ultrahigh pressure primary intermediate reheat boiler to further improve the power generation efficiency of CDQ waste heat is put forward, and the exergy efficiency is analyzed. The bottleneck problem of further improving power generation efficiency by CDQ waste heat power generation and the exergy efficiency limit under the current process conditions are obtained. More >

Jianping Deng¹, Qianqian Zhang¹, Yuling Lan¹, Lingcong Luo¹, Zimin Dai¹, Zhonghang Lin¹, Zhixin Lu¹, Jiancheng Yuan¹, Yiqi Fu¹, Lu Luo^2,*, Weigang Zhao^1,*

Journal of Renewable Materials, Vol.11, No.6, pp. 2631-2646, 2023, DOI:10.32604/jrm.2023.027163

Abstract The development and utilization of biomass and agroforestry processing byproducts for high-value applications have been an important topic in the field of renewable materials research. Based on this, a two-step microwave hydrothermal pre-carbonization and KOH activation method was proposed to synthesize tannin-based activated carbons with a high specific surface area, hierarchical pore structure, and good electrochemical performance. The microstructure, texture properties, and physicochemical characteristics were investigated. The results show that the prepared tannin-based activated carbons presented a hierarchical pore structure (micro- and mesopores) with a specific surface area as high as 997.46 m³ g⁻¹ . The electrochemical analysis shows that… More > Graphic Abstract