INVESTIGATION OF LAMINAR MIXED CONVECTION HEAT TRANSFER FROM ARRAYS OF PROTRUDED HEAT SOURCES


PIRASACI T., Sivrioglu M.

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, cilt.27, sa.4, ss.765-773, 2012 (SCI-Expanded) identifier identifier

Özet

Laminar mixed convection heat transfer in a top and bottom heated rectangular channel with protruded discrete heat sources has been investigated numerically for air. The lower and upper surfaces of the channel were equipped with 8 x 4 protruded heat sources subjected to uniform heat flux. Results show that surface temperatures increase with increasing Gr(*) numbers. For high values of Gr(*) numbers where natural convection is the dominant heat transfer regime (Gr/Re-2 > 1), temperatures of heaters can have much higher values. In this region while the row -averaged Nu numbers of top heaters decrease with the row number, the row -averaged Nu numbers of bottom heaters decrease until a certain row. After this row however, there is an increase in the row -averaged Nu number due to the effects of natural convection. As a result of this while the temperatures of top heaters increase with the row number, the temperatures of bottom heaters decrease after the certain row.