Heat Transfer in Air Flow Past a Bottom Channel Wall-Attached Diamond-Shaped Baffle – Using a CFD Technique

Abstract

A computational analysis has been conducted to investigate turbulent flow and convective thermal transfer characteristics in a two-dimensional horizontal rectangular section channel with a hot lower wall-mounted diamond-shaped baffle. The calculations are based on the finite volume method, by means of Commercial Computational Fluid Dynamics software FLUENT, standard k-epsilon turbulence model with QUICK numerical scheme, and the SIMPLE discretization algorithm has been applied. The fluid flow and heat transfer characteristics, i.e., dynamic pressure coefficient, stream function, mean, axial, and transverse velocities, turbulent viscosity, temperature field, skin friction coefficients, local and average Nusselt numbers, and thermal enhancement factor are presented for flow Reynolds numbers based on the aeraulic diameter of the computational domain ranging from 12,000 to 32,000 at constant surface temperature condition along the upper and lower walls. Effect of the diamond configuration of the insulated baffle is studied numerically and the data obtained from this same baffle model are also compared with that of the simple flat rectangular baffle under similar operating conditions. Over the range under investigation, the improvements are found to be around 3.962 and 29.820 times higher than the smooth air channel with no baffle for heat thermal transfer and skin friction factor, respectively. The maximum TEF is around 1.292 at the highest Reynolds number value, Re = 32,000.

Enhanced Heat Transfer by Oil/Multi-Walled Carbon Nano-Tubes Nanofluid

“…Figure 1c highlights the characteristics of all surfaces of the exchanger. The inlet of the exchanger conduit is subjected to a fluid flow with an axial speed related to the Re values (Reynolds number), as stated in some indexed papers such as Menni et al [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35], Demartini et al [36], and Nasiruddin and Kamran Siddiqui [37]. Five different speeds are simulated in order to demonstrate the effect of flow rate on various dynamic and thermal phenomena.…”

“…Modeling the baffles in terms of their geometry is the goal and path of many researchers in order to update the thermal and energy performance of various solar exchangers (see Kamali and Binesh [12], Wang et al [13], Fawaz et al [14], Boonloi and Jedsadaratanachai [15], Tamna et al [16], Nanan et al [17], Menni [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] in Table 1). The effect of both deflector dimension and flow rate has also been analyzed for complex geometrical obstacles, such as helical baffles.…”

Managing and Control of Nanofiltration / Reverse Osmosis Desalination System: Application of Artificial Neural Network

“…Finally, the performance of the electricity cell may be improved based on the heat exchangers [35][36][37][38][39][40][41][42][43][44][45][46] in order to reduce its temperature and increase its efficiency as a future study. Figure 11.…”

Numerical evaluation of the thermal performance of a solar air heater equipped with two different types of baffles

“…Heat‐transfer enhancement is one of the most important issues in solar air heater systems to achieve higher thermal efficiency. Based on the previous works which were carried out by the researchers, a significant number of investigations have been done about heat‐transfer enhancement or analyzing the thermal performance of the solar air heaters 15‐28 …”