Adiabatic steam-water annular flow in an annular geometry

Abstract Experimental results for fully developed steam-water annular flow in annular geometries are presented. Rod and tube film flow rates and axial pressure gradients were measured for mass fluxes between 500 and 2000 kg/m 2 s, steam qualities between 20 and 60 per cent and pressures ranging from 3 to 9 MPa. It was found that the measured tube film flow rate per unit tube perimeter is always many times greater than the corresponding rod film flow rate. Possible explanations for this asymmetry are discussed.