## Numerical Study on the Effect of Inclination Angles on Natural Convection in Entrance Region Using Regularised Lattice Boltzmann BGK Method

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences

Volume 10 No. 1, June 2015, Pages 11-26

M. Basha^{1}, C. S. Nor Azwadi^{1,*}

**1**Department of Thermo-fluids, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor, Malaysia

**Corresponding author: azwadi@fkm.utm.my*

## KEYWORDS

Lattice Boltzmann Method, Multi-Population Distribution, Natural Convection, Entrance Region, Channel

## ABSTRACT

A numerical study of incompressible laminar natural convection in entrance region of two dimensional vertical and inclined channels using Regularized Lattice Boltzmann BhatnagharGross-Krook (RLBGK) method is presented in this paper. Individual distribution functions with lattice types D2Q9 and D2Q5 are considered to solve fluid flow and thermal fields, respectively. Rayleigh number is varied from 102 to 106. The channel inclination angle is varied from 0 to 60°. Aspect ratio of channel is equal to 5. A set of distribution functions is proposed to mimic Bernoulli’s equation for calculating pressure at the inlet. Predicted velocity and temperature fields are compared with velocity and temperature fields found from finite volume code Fluent. Also, predicted Nusselt numbers are compared with Nusselt numbers correlation. Results are in good agreement with results found from FLUENT code.

## CITE THIS ARTICLE

**MLA**

Basha, M., et al. “Numerical Study on the Effect of Inclination Angles on Natural Convection in Entrance Region Using Regularised Lattice Boltzmann BGK Method.” *Journal of Advanced Research in Fluid Mechanics and Thermal Sciences* 10.1 (2015): 11-26.

**APA**

Basha, M., & Nor Azwadi, C. S. (2015). Numerical Study on the Effect of Inclination Angles on Natural Convection in Entrance Region Using Regularised Lattice Boltzmann BGK Method. *Journal of Advanced Research in Fluid Mechanics and Thermal Sciences*, 10(1), 11-26.

**Chicago**

Basha, M., and C. S. Nor Azwadi. “Numerical Study on the Effect of Inclination Angles on Natural Convection in Entrance Region Using Regularised Lattice Boltzmann BGK Method.” *Journal of Advanced Research in Fluid Mechanics and Thermal Sciences* 10, no. 1 (2015): 11-26.

**Harvard**

Basha, M. and Nor Azwadi, C.S., 2015. Numerical Study on the Effect of Inclination Angles on Natural Convection in Entrance Region Using Regularised Lattice Boltzmann BGK Method. *Journal of Advanced Research in Fluid Mechanics and Thermal Sciences*, 10(1), pp.11-26.

**Vancouver**

Basha, M, Nor Azwadi, CS. Numerical Study on the Effect of Inclination Angles on Natural Convection in Entrance Region Using Regularised Lattice Boltzmann BGK Method. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences. 2015;10(1):11-26.

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