Experiments were performed to determine the effect of flow separation on the freezing heat-transfer characteristics of a turbulent pipe flow. The flow separation was induced by an orifice situated at the inlet of an uniformly cooled circular tube. The degree of flow separation was altered by adopting orifices of various hole diameters. Water was the working fluid. Three kinds of tubes with 29.0 mm, 41.5 mm ad 62.9 mm in diameter was utilized. The Reynolds number and cooling temperature ratio, respectively, ranged from 3.2 ×103 to 1.4 ×104 and from 2.3 to 30.5. The measurements showed that the flow separation exerted a marked influence both on the local ice-formation characteristics and on the onset of freeze-off condition. The delay of the onset of the freeze-off owing to flow separation was found to be accentuated at condition of 1/2 in the ratio of the orifice to the tube diameter.
ASJC Scopus subject areas
- Mechanical Engineering