Experimental analysis of mixed convection in inclined tubes

Axial and radial velocity components for mixed convection of water in an inclined isothermal tube have been measured using a PIV technique. The results illustrate the importance and extent of flow reversal for two flow rates (2 and 5 l/h) and three tube inclinations (30°, 45° and 60°). The corresponding Reynolds numbers are below 100 while the Grashof number is approximately 1.7 × 105. These results can be used to validate numerical predictions.