Noureddine Abouricha^1,*, Chouaib Ennawaoui^1,2, Mustapha El Alami³

Frontiers in Heat and Mass Transfer, Vol.21, pp. 523-537, 2023, DOI:10.32604/fhmt.2023.045914 - 30 November 2023

Abstract This work presents a simulation of the phenomena of natural convection in an enclosure with a variable heating regime by the lattice Boltzmann method (LBM). We consider a square enclosure of side H filled with air (Pr = 0.71) and heated from below, with a hot portion of length L = 0.8 H, by imposing a sinusoidal temperature. The unheated segments of the bottom wall are treated as adiabatic, and one of the vertical walls features a cold region, while the remaining walls remain adiabatic. The outcomes of the two-dimensional (2D) problem are depicted through isotherms, streamlines, More >

Jiarui Wu¹, Yuzhen Kang², Junxiao Feng^1,*

Energy Engineering, Vol.120, No.12, pp. 2783-2802, 2023, DOI:10.32604/ee.2023.029358 - 29 November 2023

Abstract To enhance system stability, solar collectors have been integrated with air-source heat pumps. This integration facilitates the concurrent utilization of solar and air as energy sources for the system, leading to an improvement in the system's heat generation coefficient, overall efficiency, and stability. In this study, we focus on a residential building located in Lhasa as the target for heating purposes. Initially, we simulate and analyze a solar-air source heat pump combined heating system. Subsequently, while ensuring the system meets user requirements, we examine the influence of solar collector installation angles and collector area on More >

Qingguo Liu^1,2, Umut Hanoglu^1,2, Božidar Šarler^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09609

Abstract A simulation of reheating furnace in a steel production line where the steel billets are heated from room temperature up to 1200 ˚C, is carried out using a novel meshless solution procedure. The reheating of the steel billets before the continuous hot-rolling process should be employed to dissolve alloying elements as much as possible and redistribute the carbon. In this work, governing equations are solved by the local radial basis function collocation method (LRBFCM) in a strong form with explicit time-stepping. The solution of the diffusion equations for the temperature and carbon concentration fields is… More >

Dangqiang Wang¹, Hai Mei^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09455

Abstract The densification process of sintered alumina is mainly controlled by surface, lattice, and interface diffusion, and many experimental researches show that heating rate can affect the transfer of matter. Thus, to further reveal the effect of heating rate on sintering mechanism of alumina nanoparticle, molecular dynamic simulations were performed at five different heating rates to examine the migration of atoms and evolution of microstructure in heating stage. Results show that the sintering process of heating is a typical thermal activation process. High displacement response temperature is caused by high heating rate, which results in the More >

Nosheen Fatima¹, Nabeela Kousar¹, Khalil Ur Rehman^2,3,*, Wasfi Shatanawi^2,4,5

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.3, pp. 2311-2330, 2023, DOI:10.32604/cmes.2023.026994 - 03 August 2023

Abstract A computational analysis of magnetized hybrid Darcy-Forchheimer nanofluid flow across a flat surface is presented in this work. For the study of heat and mass transfer aspects viscous dissipation, activation energy, Joule heating, thermal radiation, and heat generation effects are considered. The suspension of nanoparticles singlewalled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are created by hybrid nanofluids. However, single-walled carbon nanotubes (SWCNTs) produce nanofluids, with water acting as conventional fluid, respectively. Nonlinear partial differential equations (PDEs) that describe the ultimate flow are converted to nonlinear ordinary differential equations (ODEs) using appropriate similarity transformation.… More >

Jingxiao Han¹, Chuanzhao Zhang², Lu Wang^3,*, Zengjun Chang¹, Qing Zhao¹, Ying Shi⁴, Jiarui Wu⁵, Xiangfei Kong³

Energy Engineering, Vol.120, No.9, pp. 1991-2011, 2023, DOI:10.32604/ee.2023.029749 - 31 July 2023

Abstract For heating systems based on electricity storage coupled with solar energy and an air source heat pump (ECSA), choosing the appropriate combination of heat sources according to local conditions is the key to improving economic efficiency. In this paper, four cities in three climatic regions in China were selected, namely Nanjing in the hot summer and cold winter region, Tianjin in the cold region, Shenyang and Harbin in the severe cold winter region. The levelized cost of heat (LCOH) was used as the economic evaluation index, and the energy consumption and emissions of different pollutants… More > Graphic Abstract

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 - 16 May 2023

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 More > Graphic Abstract

Guoqing Yu^1,*, Nan Fang¹, Dingke Hu², Wei Zhao³

Energy Engineering, Vol.120, No.7, pp. 1563-1582, 2023, DOI:10.32604/ee.2023.026951 - 04 May 2023

Abstract In the hot summer & cold winter zone in China, intermittent heating space for rooms is widely used. However, in comparison with continuous space heating, the energy-saving performance of intermittent space heating has not been sufficiently investigated. This paper studied the factors influencing the energy performance of intermittent heating for the representative office in hot summer & cold winter zone. Based on the heat balance method, a dynamic thermal model of the intermittent heating room was built and tested by experiments. And then, it analyzed the total space heating load, the amount of energy saving… More >

Ibrahim Aliyu¹, Tai-Won Um², Sang-Joon Lee³, Chang Gyoon Lim^4,*, Jinsul Kim^1,*

CMC-Computers, Materials & Continua, Vol.75, No.3, pp. 5947-5964, 2023, DOI:10.32604/cmc.2023.037202 - 29 April 2023

Abstract In the quest to minimize energy waste, the energy performance of buildings (EPB) has been a focus because building appliances, such as heating, ventilation, and air conditioning, consume the highest energy. Therefore, effective design and planning for estimating heating load (HL) and cooling load (CL) for energy saving have become paramount. In this vein, efforts have been made to predict the HL and CL using a univariate approach. However, this approach necessitates two models for learning HL and CL, requiring more computational time. Moreover, the one-dimensional (1D) convolutional neural network (CNN) has gained popularity due… More >

Le Anh Duc^a , Pham Van Kien^b,*, Nguyen Thanh Tan^b, Doan Thanh Son^b, Nhanh Van Nguyen^c, Ngoc Xuan Nguyen^d

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-6, 2023, DOI:10.5098/hmt.20.25

Abstract This study focused on the heat and mass transfer in radio (RF) assisted heat pump (HP) drying of carrots. The experimental drying of carrot by RF assisted HP drying method was conducted to evaluate the effect of RF power on drying efficiency including drying rate and heating rate. The input drying parameters were drying air temperature of 45oC, drying air velocity of 2.5 m/s and RF power of 0, 0.5 and 1.5 kW, in which, RF power of 0 was corresponding to HP drying method. The experimental drying results showed that in RF assisted HP… More >