Yun Hao^* , Shaohua Lv, Song Wu

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-8, 2022, DOI:10.5098/hmt.18.3

Abstract Traditional methods of enhancing the thermal efficiency of heating furnaces in continuously producing oilfields, such as replacing existing units with more efficient units or renovating old furnaces, are highly inconvenient. This paper studied on the characteristics of nanofluids, a novel heat transfer medium with excellent heat transfer characteristics to enhance the thermal efficiency of heating furnaces. The stable nanofluids (Al₂O₃-H₂O, SiO₂- H₂O, and TiO₂-H₂O) were prepared by a two-step method and various chemical and physical treatments were carried out. Thermal conductivities of the nanofluids were measured using the transient hot-wire method. Based on the analysis, the most More >

Namphon Pipatpaiboon^a , Teerapat Chompookham^b, Sampan Rittidech^b, Yulong Ding^c, Thanya Parametthanuwat^d, Surachet Sichamnan^a,*

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-9, 2022, DOI:10.5098/hmt.19.24

Abstract When nanofluid (NF) is used as the working fluid in a rectangular two-phase closed thermosyphon (RTPCT), the formations and heat performance of two-phase flow patterns are explored qualitatively. Silver nanoparticles were mixed with deionized water at a concentration of 0.5 wt% in the NF. Nanoparticles improved the thermal contact surface area within the base flow, allowing the base fluid to boil quickly and easily. When the working fluid was boiled, NF also demonstrated high thermal conductivity capabilities, which diffused and moved along with the dual flow patterns. As a result, these qualities improved the RTPCT's More >

Lanqi Chen, Yuwei Wang, Cong Qi^*, Zhibo Tang, Zhen Tian

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.5, pp. 1205-1227, 2022, DOI:10.32604/fdmp.2022.021200 - 27 May 2022

Abstract Nowadays, the utilization rate of electronic products is increasing while showing no obvious sign of reaching a limit. To solve the associated “internal heat generation problem”, scientists have proposed two methods or strategies. The first approach consists of replacing the heat exchange medium with a nanofluid. However, the high surface energy of the nanoparticles makes them prone to accumulate along the heat transfer surface. The second method follows a different approach. It tries to modify the surface structure of the electronic components in order to reduce the fluid-dynamic drag and improve the rate of heat More > Graphic Abstract

Tahir Kamran, Muhammad Imran^*, Muhammad N. Naeem, Mohsan Raza

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.2, pp. 1023-1039, 2022, DOI:10.32604/cmes.2022.017391 - 14 March 2022

Abstract Currently, nanofluid is a hot area of interest for researchers. The nanofluid with bioconvection phenomenon attracted the researchers owing to its numerous applications in the field of nanotechnology, microbiology, nuclear science, heat storage devices, biosensors, biotechnology, hydrogen bomb, engine of motors, cancer treatment, the atomic reactor, cooling of devices, and in many more. This article presents the bioconvection cross-diffusion effects on the magnetohydrodynamic flow of nanofluids on three different geometries (cone, wedge, and plate) with mixed convection. The temperature-dependent thermal conductivity, thermal diffusivity, and Arrhenius activation energy applications are considered on the fluid flow with… More >

Yuling Zhai^*, Long Li, Zihao Xuan, Mingyan Ma, Hua Wang

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.3, pp. 629-646, 2022, DOI:10.32604/fdmp.2022.017485 - 22 February 2022

Abstract The thermo-physical properties of nanofluids are highly dependent on the used base fluid. This study explores the influence of the mixing ratio on the thermal conductivity and viscosity of ZnO-CuO/EG (ethylene glycol)-W (water) hybrid nanofluids with mass concentration and temperatures in the ranges 1-5 wt.% and 25-60°C, respectively. The characteristics and stability of these mixtures were estimated by TEM (transmission electron microscopy), visual observation, and absorbance tests. The results show that 120 min of sonication and the addition of PVP (polyvinyl pyrrolidone) surfactant can prevent sedimentation for a period reaching up to 20 days. The… More >

Junaid Khan, Rashid Ali, Muzammil Zubair, Syed Mohd Yahya^*

Energy Engineering, Vol.119, No.2, pp. 827-846, 2022, DOI:10.32604/ee.2022.016344 - 24 January 2022

Abstract Cooling the PV surface in a Photovoltaic Thermal system is a pivotal operational aspect to be taken into account to achieve optimized values of performance parameters in a Photovoltaic Thermal System. The experimental design used in this study facilitates the flow of varying concentrations of Zn-water nanofluid in serpentine copper tubing installed at the rear of the PV panel thereby preventing the PV surface temperature from increasing beyond the threshold value at which a decrease in electrical efficiency starts to occur. This fusion of solar thermal with PV devices leads to better electrical and thermal… More >

Mamdouh El Haj Assad¹, Ibrahim Mahariq², Raymond Ghandour², Mohammad Alhuyi Nazari³, Thabet Abdeljawad^4,5,6,*

CMC-Computers, Materials & Continua, Vol.70, No.1, pp. 361-374, 2022, DOI:10.32604/cmc.2022.019048 - 07 September 2021

Abstract Nanofluids are extensively applied in various heat transfer mediums for improving their heat transfer characteristics and hence their performance. Specific heat capacity of nanofluids, as one of the thermophysical properties, performs principal role in heat transfer of thermal mediums utilizing nanofluids. In this regard, different studies have been carried out to investigate the influential factors on nanofluids specific heat. Moreover, several regression models based on correlations or artificial intelligence have been developed for forecasting this property of nanofluids. In the current review paper, influential parameters on the specific heat capacity of nanofluids are introduced. Afterwards, More >

Kaprawi Sahim^*, Dewi Puspitasari, Nukman

Frontiers in Heat and Mass Transfer, Vol.16, pp. 1-6, 2021, DOI:10.5098/hmt.16.22

Abstract The recent trend application of the nanofluids is used in some industrial equipment such as tube heat exchanger, double pipe exchanger and shell-tube type heat exchanger. The Triangle tubes may be used in the heat exchanger. Thus, this experimental study reports the convective heat transfer performance of the aluminum oxide-water nanofluids flowing in the triangle channel. In this study, the amount of the volume fraction of the Al₂O₃ used was 0.1 %, 0.2 %, and 0.3 respectively in base-water as the nanofluids and the Reynolds numbers were varied from about 1000 to 7000. The channel was… More >

Kafel Azeez Mohammed^a,*, Ahmed Mustaffa Saleem^b , Zain alabdeen H. Obaid^a

Frontiers in Heat and Mass Transfer, Vol.16, pp. 1-8, 2021, DOI:10.5098/hmt.16.20

Abstract Numerical investigation is performed for the determination of Nusselt number of ZnO, TiO₂ and SiO₂ nanoparticles dispersed in 60% ethylene glycol and 40% water inside inclined cylinder for adiabatic and isothermal process. The present study was conducted for both the constant heat flux (10,000 W/m²) and constant wall temperature (313.15 K) boundary conditions. At the inlet, the uniform axial velocity and initial temperature (293 K) were assumed. The results show the change of average Nusselt number at Reynolds number (400), Rayleigh number (10⁶) and volume fraction percentage (2%). From results for adiabatic process when increasing the slop More >

Sheikh Hassan¹, Didarul Ahasan Redwan¹, Md. Mamun Molla^1,2,*, Sharaban Thohura³, M. Abu Taher⁴, Sadia Siddiqa⁵

Energy Engineering, Vol.118, No.6, pp. 1659-1679, 2021, DOI:10.32604/EE.2021.017657 - 10 September 2021

Abstract A two-dimensional (2D) laminar flow of nanofluids confined within a square cavity having localized heat source at the bottom wall has been investigated. The governing Navier–Stokes and energy equations have been non dimensionalized using the appropriate non dimensional variables and then numerically solved using finite volume method. The flow was controlled by a range of parameters such as Rayleigh number, length of heat source and nanoparticle volume fraction. The numerical results are represented in terms of isotherms, streamlines, velocity and temperature distribution as well as the local and average rate of heat transfer. A comparative More >