A review of magnetic field influence on natural convection heat transfer performance of nanofluids in square cavities

2020 ◽  
Author(s):  
S. O. Giwa ◽  
M. Sharifpur ◽  
M. H. Ahmadi ◽  
J. P. Meyer
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Natural Convection ◽  
Heat Transfer Performance ◽  
Convection Heat Transfer ◽  
Natural Convection Heat Transfer ◽  
Transfer Performance ◽  
Convection Heat ◽  
Field Influence

scholarly journals Heat Transfer Performance of Different Fluids During Natural Convection in Enclosures with Varying Aspect Ratios

2021 ◽  
Vol 287 ◽  
pp. 03010
Author(s):  
Rajashekhar Pendyala ◽  
Suhaib Umer Ilyas ◽  
Yean Sang Wong
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Natural Convection ◽  
Heat Transfer Performance ◽  
Convection Heat Transfer ◽  
Heat Transfer Process ◽  
Natural Convection Heat Transfer ◽  
Transfer Performance ◽  
Convection Heat ◽  
Aspect Ratios

The heat transfer process takes place in numerous applications through the natural convection of fluids. Investigations of the natural convection heat transfer in enclosures have gained vital importance in the last decade for the improvement in thermal performance and design of the heating/cooling systems. Aspect ratios (AR=height/length) of the enclosures are one of the crucial factors during the natural convection heat transfer process. The investigated fluids consisting of air, water, engine oil, mercury, and glycerine have numerous engineering applications. Heat transfer and fluid flow characteristics are studied in 3-dimensional rectangular enclosures with varying aspect ratios (0.125 to 150) using computational fluid dynamics (CFD) simulations. Studies are carried out using the five different fluids having Prandtl number range 0.01 to 4500 in rectangular enclosures with the hot and cold surface with varying temperature difference 20K to 100K. The Nusselt number and heat transfer coefficients are estimated at all conditions to understand the dependency of ARs on the heat transfer performance of selected fluids. Temperature and velocity profiles are compared to study the flow pattern of different fluids during natural convection. The Nusselt number correlations are developed in terms of aspect ratio and Rayleigh number to signify the natural convection heat transfer performance.

scholarly journals Experimental Observation of Natural Convection Heat Transfer Performance of a Rectangular Thermosyphon

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1702 ◽  
Author(s):  
C. S. Huang ◽  
Chia-Wang Yu ◽  
R. H. Chen ◽  
Chun-Ta Tzeng ◽  
Chi-Ming Lai
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Heat Transfer Performance ◽  
Thermal Power ◽  
Convection Heat Transfer ◽  
Natural Convection Heat Transfer ◽  
Transfer Performance ◽  
Convection Heat ◽  
Heating Section ◽  
Cooling Section

This study experimentally investigates the natural convection heat transfer performance of a rectangular thermosyphon with an aspect ratio of 3.5. The experimental model is divided into a loop body, a heating section, a cooling section, and two adiabatic sections. The heating section and the cooling section are located in the vertical legs of the rectangular loop. The length of the vertical heating section and the length of the upper and lower horizontal insulation sections are 700 mm and 200 mm, respectively, and the inner diameter of the loop is 11 mm. The relevant parameters and their ranges are as follows: the input thermal power is 30–60 W (with a heat flux in the range of 60–3800 W/m2); the temperature in the cooling section is 30, 40, or 50 °C; and the potential difference between the hot and cold sections is 5, 11, or 18 for the cooling section lengths of 60, 45, and 30 cm, respectively. The results indicate that the value of the dimensionless heat transfer coefficient, the Nusselt number, is generally between 5 and 10. The heating power is the main factor affecting the natural convection intensity of the thermosyphon.

A Study on Improving in Natural Convection Heat Transfer for Heat Sink of High Power LEDs

2011 ◽  
Vol 383-390 ◽  
pp. 6834-6839 ◽  
Author(s):  
Xiang Rui Meng ◽  
Xin Ling Ma ◽  
Ji Fu Lu ◽  
Xin Li Wei
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Heat Sink ◽  
Heat Transfer Performance ◽  
Convection Heat Transfer ◽  
Natural Convection Heat Transfer ◽  
Transfer Performance ◽  
Stagnation Zone ◽  
Convection Heat ◽  
Symmetry Center

In this paper the natural convection heat transfer performance of horizontal heat sink was studied by numerical simulation and experiment. The numerical simulation results show that there are some interesting features in the flow field of heat sink model. 1) Among the fins, the air vertically flows only through the fins in the symmetry center of heat sink while it horizontally flows through the fins in other area. 2) There is an air stagnation zone located at the fin root in the symmetry center of heat sink. These features both caused the decrease in heat transfer temperature difference and heat transfer area in fact. The natural convection heat transfer performance of heat sink is affected at last. In order to eliminate the air stagnation zone and change in the flow way of air, some holes were perforated at the fin root. These holes play its role. In this test, the heat transfer power of heat sink with seven holes has increased by 16.7% compared with the prototype.With the increase in the number of holes, the natural convection heat transfer power of heat sink also increases. But when the number of holes reaches to a value, the increase in the number of holes will not function properly.

Sign in / Sign up

Export Citation Format

Share Document