Convegni ATI - Accesso riservato soci CTI

Autore: G. Sotgia, P. Tartarini

Collana: BT - 34 - Mag 06 - Energy: production, distribution and conservation

Note:
In the present work, the experimental activities conducted in the laboratories of the Polytechnic University of Milan are reported. Experimental tests have been conducted on smooth, horizontal and inclined tubes of Pyrex with internal diameter of 40 mm, 11 m of total length and 4 m of test section length. Six operating conditions were examined: horizontal pipe, upward slopes of 1.5°, 3°. 4.5° and 6°, and 1.5° downward slope. Mineral oil and tap water were used, with a viscosity ratio of about 800 and a density ratio of about 0.9. The influence of different parameters on the pressure drop in oil-water flows has been evaluated. Some peculiar behaviours of the pressure drop reduction as a function of the water volume fraction are observed. In particular, two alternative behaviours were observed: a critical transition between different flow patterns, corresponding to a sudden increase of the pressure drop, and a gradual flow pattern transition about an optimal situation of minimum pressure drop.
Some tests on the same apparatus were conducted injecting air into the oil-water flow.
The preliminary results and considerations on that three-phase experimental campaign are finally presented.