Kun Zhang^a,b,* , Zhiyong Li^a,b, Jia Yao^a,b

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.5

Abstract Detailed numerical analysis is presented for heat transfer characteristics of charging or discharging process in phase change thermal energy storage unit with inner corrugated tube. The results indicated that the charging or discharging rate of phase change material (PCM) for the case of inner corrugated tube is obviously higher than that in unit with inner plain tube due to the increasing heat transfer surface. The heat transfer rate increase with the increasing mass flow rate. However, when the mass flow rate of heat transfer fluid (HTF) is greater than 0.0315kg/s, the charge and discharge time can not be obviously shorten… More >

O. M. Oyewola^a,b,* , M. O. Petinrin^a , and H. O. Sanusi^a

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-8, 2023, DOI:10.5098/hmt.20.16

Abstract The flow and heat transfer behaviour of channels with dimples and protrusions of spherical and piriform shapes was numerically explored by solving the Navier-Stokes and energy equations with a CFD software, the ANSYS Fluent 19.3, in the range of Reynolds numbers from 8,500 to 59,000. The values of the Nusselt number and friction factors were estimated and the non-dimensional Performance Evaluation Criterion (PEC) was determined to measure the thermal-hydraulic performance. The results reveal that the piriform protruded channel demonstrated a higher thermal performance with Nusselt number values of 36%, 15%, 23%, and 9% than the smooth, spherical dimpled, piriform dimpled,… More >

Shrikant Arunrao Thote^*, Netra Pal Singh

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 711-722, 2023, DOI:10.32604/fdmp.2022.021651

Abstract The thermo-hydraulic properties of circular tubes with a twisted tape inside (used accordingly to induce turbulence and enhance heat transfer through the tube wall) are described for Reynolds Numbers ranging from 830 to 1990. Tapes twisted with the three distinct twist ratios are considered, namely, 6, 4.4 and 3. Air is used as the working fluid in several tests. For the sake of comparison, the standard tube with no insert is also examined. It is shown that in the presence of the twisted tape, the ‘frictional factor’, ‘Nusselt Number’ and the ‘thermal performance factor’ are much higher than those obtained… More >

Yajuan Jia¹, Lisha Shang¹, Jiangping Nan¹, Guangping Hu², Zhigang Fang^3,4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 329-344, 2022, DOI:10.32604/fdmp.2022.017734

Abstract The flow past a fixed single transmission conductor and the related heat transfer characteristics are investigated using computational fluid dynamics and a relevant turbulence model. After validating the method through comparison with relevant results in the literature, this thermofluid-dynamic problem is addressed considering different working conditions. It is shown that the resistance coefficient depends on the Reynolds number. As expected, the Nusselt number is also affected by Reynolds number. In particular, the Nusselt number under constant heat flux is always greater than that under a constant wall temperature. More >

Yukun Lv, Zhuang Wei^*, Quanzhi Ge, Fan Yang, Shuang Yang

Energy Engineering, Vol.118, No.6, pp. 1855-1867, 2021, DOI:10.32604/EE.2021.015248

Abstract The water-cooling heat dissipation technology can solve the heat dissipation and noise problems of the calculation plate. Therefore, the structural design of the water-cooling plate directly affects its flow and heat transfer characteristics, which restricts the promotion and application of the technology. To this end, the water-cooling plate of a heat dissipation system was taken as the research object, and its flow and heat transfer characteristics were numerical simulated and experimental studied. Through comparative analysis, the rationality of the numerical simulation method was verified. Based on this, three improved schemes of water-cooling plate structure were proposed and numerical simulation was… More >

Cong Qi^*, Yuxing Wang, Zi Ding, Jianglin Tu, Mengxin Zhu

Energy Engineering, Vol.118, No.4, pp. 825-852, 2021, DOI:10.32604/EE.2021.014806

Abstract Boiling heat transfer is a mode using the phase change of working medium to strengthen the heat exchange due to its good heat exchange capability, and it is widely used in heat exchange engineering. Nanofluids have been used in the direction of enhanced heat transfer for their superior thermophysical property. The wetting, spreading and ripple phenomena of superhydrophobic surfaces widely exist in nature and daily life. It has great application value for engineering technology. In this article, the boiling heat exchange characteristics of nanofluids on superhydrophobic surface are numerically studied. It was found that with the increase of superheating degree,… More >

Cong Qi^1,2,*, Chengchao Wang^1,2, Jinghua Tang^1,2, Dongtai Han²

Energy Engineering, Vol.117, No.2, pp. 63-78, 2020, DOI:10.32604/EE.2020.010433

Abstract Because of the poor thermal performance of ordinary tubes, a triangular tube was used to replace the smooth channel in the heat transfer system, and nanofluids were used to take the place of ordinary fluids as the heat transfer medium. High stability nanofluids were prepared, and an experimental set on flow and heat exchange was established. Effects of triangular tube rotation angles (α = 0°, 30°, 60°) as well as mass fractions of nanofluids (ω = 0.1%, 0.3%, 0.5%) on heat exchange and flow performance were experimentally considered at Reynolds numbers (Re = 800–8000). It was shown that the triangular… More >

Yiming Fan^1,2, Jingfu Wang^1,2

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.3, pp. 167-167, 2019, DOI:10.32604/icces.2019.05590

Abstract In order to investigate the dynamics and heat transfer characteristics of granulated molten blast furnace slag by blast air, a mathematical model for the dynamics and heat transfer of high temperature molten slag granulated by gas was established and solved through the fourth order Runge-Kutta algorithm, the calculation program was compiled by FORTRAN. Considering that the efficiency of air cooling is low, a method of spray cooling was presented to improve the cooling rate. And the effect of varied particle size on movement and cooling was also researched. The variation of main thermal physical properties of slag and air with… More >