A numerical investigation on 2-dimensional steady-state mixed convection in a vertical channel asymmetrically heated with water-alumina (Al2O3) nanofluids has been conducted to assess the aspect ratio's impact on thermal and fluid dynamic behaviors. This research is of interest due to its relevance to various technological applications such as nuclear reactors and electronic components. The nanoparticles used have a fixed diameter of 30 nm, and four different concentrations (ranging from 0 to 6%) were examined. The computational domain comprises the channel and two lateral reservoirs, which mimic the external ambient conditions. The channel is defined by two vertical parallel plates: one plate is subjected to a constant heat flux, while the other plate moves in the direction of buoyancy. The governing equations were solved numerically using the finite volume method with the ANSYS-Fluent code. Three different aspect ratios of the channel (5, 10, and 20), seven wall heat flux values (corresponding to Ra=7*102 to 106), and six velocities of the unheated plate (with Re=1 to 102) were considered. The results are presented in terms of velocity, temperature, shear stress, and stream function. Additionally, correlations for predicting the average Nusselt number along the heated plate are provided.
NUMERICAL INVESTIGATION ON MIXED CONVECTION WITH NANOFLUIDS IN VERTICAL CHANNELS WITH DIFFERENT ASPECT RATIOS AND MOVING PLATE
Buonomo B.;Manca O.
;Nardini S.;Sarli G.
2024
Abstract
A numerical investigation on 2-dimensional steady-state mixed convection in a vertical channel asymmetrically heated with water-alumina (Al2O3) nanofluids has been conducted to assess the aspect ratio's impact on thermal and fluid dynamic behaviors. This research is of interest due to its relevance to various technological applications such as nuclear reactors and electronic components. The nanoparticles used have a fixed diameter of 30 nm, and four different concentrations (ranging from 0 to 6%) were examined. The computational domain comprises the channel and two lateral reservoirs, which mimic the external ambient conditions. The channel is defined by two vertical parallel plates: one plate is subjected to a constant heat flux, while the other plate moves in the direction of buoyancy. The governing equations were solved numerically using the finite volume method with the ANSYS-Fluent code. Three different aspect ratios of the channel (5, 10, and 20), seven wall heat flux values (corresponding to Ra=7*102 to 106), and six velocities of the unheated plate (with Re=1 to 102) were considered. The results are presented in terms of velocity, temperature, shear stress, and stream function. Additionally, correlations for predicting the average Nusselt number along the heated plate are provided.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.