... to the combination of buoyancy forces acting in same direction generated at the bottom and top portions of the annulus and greatly strengthens the fluid movement. However, for other two cases, the buoyancy forces are acting in the opposite directions and thus lead to a multicellular flow structure with reduced flow...

...Caleb S. Brooks; Nicolás Silin; Takashi Hibiki; Mamoru Ishii 13 08 2013 30 12 2014 03 02 2015 Wall nucleation experiments have been performed in a vertical annulus test section for investigation of the bubble departure diameter and bubble departure frequency...

... ¯ dropped to values that were roughly 60% lower than that in the concentric case. This demonstrates that high eccentricity causes a deterioration of heat transfer not only in the narrow gap region but also in the entire annulus. 1 Corresponding author. Contributed by the Heat Transfer Division...

... and nanoparticle size. It was observed that for Ra ≥ 10 4 , the average Nusselt number was deteriorated by increasing the volume fraction of nanoparticles. However, for Ra = 10 3 , the average Nusselt number enhancement depends on aspect ratio of the annulus as well as volume fraction of nanoparticles. Also...