Abstract
The natural convection heat transfer has many applications in engineering like solar collectors, cooling of electronic equipment and geothermal engineering. The present work demonstrates the recent publications in the last ten years in this specific subject for a body located in complex shapes like rhombic, wavy, trapezoidal, elliptical and Parallelogrammic enclosure. Many parameters like Ra, Nu, number of undulations, the position of the inner body had been addressed and discuss to draw the main conclusions and recommendations. It is worthy to mention that wavy enclosure had been investigated less than the other simple enclosure shapes due to its complexity. Beside that entropy generation should be included in the future studies in complex shapes of enclosure as this will helps the researchers to extended their studies. The inner bodies inside trapezoidal, parallelogrammic enclosure are very limited and more investigation should be done.
