Document Type : Article

**Author**

Mechanical Engineering Department, Yasouj university, Yasouj, Iran.

**Abstract**

In the present work, a numerical method to solve the problem of free convec-

tion in enclosures with complex geometries is developed. This development is

executed by the combination of projection and Galerkin nite element methods.

Nine-node (quadratic) quadrilateral elements are used to generate the grid for

the eld of the problem. The results show that the convergence of this method

is acceptable, while there is no necessity to use upwind schemes. Increasing

the numbers of nodes and decreasing the time increment yield a more accurate

solution. The advantages of this numerical method are the ability to model any

complex geometry and no necessity to use upwind schemes.

tion in enclosures with complex geometries is developed. This development is

executed by the combination of projection and Galerkin nite element methods.

Nine-node (quadratic) quadrilateral elements are used to generate the grid for

the eld of the problem. The results show that the convergence of this method

is acceptable, while there is no necessity to use upwind schemes. Increasing

the numbers of nodes and decreasing the time increment yield a more accurate

solution. The advantages of this numerical method are the ability to model any

complex geometry and no necessity to use upwind schemes.

**Keywords**

- free convection
- enclosures with complex geometries
- galerkin method
- Finite Element Method
- projection method

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Transactions on Mechanical Engineering (B)

May and June 2018Pages 1189-1196