ABSTRACT
The effects of natural and forced convection on mass transfer were investigated, especially the composition-dependent material properties were used. Under natural convection, the stationary specimen became a cone. The mass transfer coefficient increased from 3.14 × 10−5 to 5.31 × 10−5 m s−1 at the temperatures of 1300–1450°C. The empirical formulas Sh = 0.144(GrSc)0.325 and k = M(Δρ)0.325(L)−0.025 were found within the ranges of 1 × 108 < GrSc < 5 × 108. Under forced convection, the rotating scrap cylinder became an irregular spiral. When the rotational speed changed from 141 to 423 r min−1, the mass transfer coefficients were 7.50 × 10−5–1.72 × 10−4 m s−1 at the temperatures of 1300-1400°C. The empirical formulas JD = 0.133(Re)−0.356 and k = M(n)0.644(L)0.288 were obtained within the ranges of 1000 < Re < 4000.
Disclosure statement
No potential conflict of interest was reported by the authors.