Cover
Vol. 14 No. 2 (2014)

Published: June 30, 2014

Pages: 216-228

Original Article

Transient Buoyancy- Driven Laminar Convection in an Inclined Three- Dimensional Trapezoidal Enclosure.

Abstract

Numerical analysis of transient laminar three- dimensional buoyancy-driven convection in an inclined three- dimensional trapezoidal air-filled enclosure was investigated in this paper. The right and left sidewalls of the enclosure are kept at constant cold temperatures. The bottom wall is maintained at a constant hot temperature , while the top wall is considered adiabatic. Numerical investigation is performed for Rayleigh numbers varied as 10 3 ≤ Ra ≤ 10 5 , while the trapezoidal enclosure inclination angle is varied as 0° ≤  ≤ 180°. Prandtl number is considered constant at Pr = 0.71. Flow and thermal fields are presented in both two and three- dimensional pattern. Also, both local and average Nusselt numbers are calculated and discussed. The results show that when the Rayleigh number increases, the flow patterns are changed especially in three-dimensional results and the flow circulation increases. The minimum average Nusselt number inside the trapezoidal cavity corresponds to the highest    180 ].While, the average Nusselt inclination angle [i.e.,    30 . Moreover, number reaches its maximum value at when the Rayleigh number increases the average Nusselt number increases as expected.

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