Mixed convection from an open cavity in a horizontal channel

Heat transfer results for mixed convection from a bottom heated open cavity subjected to an external flow are reported in this study for a wide range of the governing parameters (i.e., 1 ≤ Re ≤ 2000, 0 ≤ Gr ≤ 10⁶) over cavities with various aspect ratios (A = 0.5, 1, 2 and 4). It has been found that the Reynolds number and Garshof number control the flow pattern and the occurrence of recirculating cells while the aspect ratio has a significant influence on the orientation of these cells. Heat transfer from the cavity base approaches that of natural convection at a low Reynolds number (i.e., the asymptotic natural convection regime) and approaches that of forced convection at a high Reynolds number (i.e., the asymptotic forced convection regime). In the mixed convection regime, the heat transfer rate is reduced and the flow may become unstable. A unique heat transfer correlation which covers all three convection regimes is also presented.