Hashem Shatnawi^1,2,*, Chin Wai Lim², Firas Basim Ismail³, Abdulrahman Aldossary¹

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 1693-1711, 2021, DOI:10.32604/cmc.2021.016741

Abstract The receiver is an important element in solar energy plants. The principal receiver’s tubes in power plants are devised to work under extremely severe conditions, including excessive heat fluxes. Half of the tube’s circumference is heated whilst the other half is insulated. This study aims to improve the heat transfer process and reinforce the tubes’ structure by designing a new receiver; by including longitudinal fins of triangular, circular and square shapes. The research is conducted experimentally using Reynolds numbers ranging from 28,000 to 78,000. Triangular fins have demonstrated the best improvement for heat transfer. For Reynolds number value near 43,000… More >

Jingying Li¹, Tiejun Zhu¹, Fengming Li¹, Dong Wang¹, Xianbiao Bu², Lingbao Wang^2,*

Energy Engineering, Vol.118, No.3, pp. 517-534, 2021, DOI:10.32604/EE.2021.014464

Abstract The single well geothermal heating (SWGH) technology has attracted extensive attention. To enhance heat extraction from SWGH, a mathematical model describing heat transfer is set up, and the key influence factor and heat transfer enhancement method are discussed by thermal resistance analysis. The numerical results show that the thermal resistance of rock is far greater than that of well wall and fluid. So, reducing rock thermal resistance is the most effective method for enhancing the heat extraction power. For geothermal well planning to drill: rock thermal resistance can be reduced by increasing well diameter and rock thermal conductivity; the temperature… More >

Daoming Shen^1,*, Xia Zhang¹, Wei He¹, Jinhong Xia¹, Songtao Xue²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.6, pp. 1259-1272, 2020, DOI:10.32604/fdmp.2020.010951

Abstract Experiments about heat transfer in the presence of a two-phase flow due to the condensation of a R1234yf refrigerant have been performed considering a smooth tube and two micro-fin tubes. The following experimental conditions have been considered: Condensation temperatures of 40°C, 43°C and 45°C, mass fluxes of 500–900 kg/(m² ·s), vapor qualities at the inlet and outlet of the heat transfer tube in the ranges 0.8–0.9 and 0.2–0.3, respectively. These tests have shown that: (1) The heat transfer coefficient increases with decreasing the condensation temperature and on increasing the mass flux; (2) The heat transfer coeffi- cient inside the micro-fin… More >

Anees Imtiaz¹, Oi-Mean Foong², Aamina Aamina¹, Nabeel Khan¹, Farhad Ali^{3, 4, *}, Ilyas Khan⁵

CMC-Computers, Materials & Continua, Vol.65, No.1, pp. 171-192, 2020, DOI:10.32604/cmc.2020.011397

Abstract Gold metallic nanoparticles are generally used within a lab as a tracer, to uncover on the presence of specific proteins or DNA in a sample, as well as for the recognition of various antibiotics. They are bio companionable and have properties to carry thermal energy to tumor cells by utilizing different clinical approaches. As the cancer cells are very smaller so for the infiltration, the properly sized nanoparticles have been injected in the blood. For this reason, gold nanoparticles are very effective. Keeping in mind the above applications, in the present work a generalized model of blood flow containing gold… 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 >

W. A. El-Askary, A. Abdel-Fattah

CMES-Computer Modeling in Engineering & Sciences, Vol.83, No.4, pp. 425-458, 2012, DOI:10.3970/cmes.2012.083.425

Abstract In the present paper, experimental and numerical studies of heat transfer and the frictional head loss of turbulent flow in a duct with a heated upper surface are performed. Four different arrangements are considered (case 1: without baffles, case 2: one perforated baffle on the upper wall and one solid baffle on the lower wall, case 3: one perforated baffle on the upper wall and one perforated baffle on the lower wall and case 4: two perforated baffles on the upper wall). A numerical code developed by the present authors is simultaneously presented including four different turbulence models; namely: the… More >

Fatima-zohra Bensouici^{1, *}, Saadoun Boudebous²

FDMP-Fluid Dynamics & Materials Processing, Vol.13, No.3, pp. 189-212, 2017, DOI:10.3970/fdmp.2017.013.189

Abstract A numerical work has been performed to analyze the laminar mixed convection of nanofluids confined in a lid driven square enclosure with a central square and isotherm heat source. All the walls are cooled at constant temperature, and the top wall slides rightward at constant velocity. The simulations considered four types of nanofluids (Cu, Ag, Al₂O₃ and TiO₂)-Water. The governing equations were solved using finite volume approach by the SIMPLER algorithm. Comparisons with previously published work are performed and found to be in good agreement. The influence of pertinent parameters such as Richardson number, size of the heat source, solid… More >