The concentration and velocity profiles of particles were measured for solid-liquid two-phase flow through vertical and horizontal tubes by a conventional photographic method, and through vertical tubes by two newly developed laser methods. Solid materials used were ion-exchange resin particles and glass beads with diameters of 321 to 1840 μm and densities of 1190 to 2500 kg/m³. Tube diameters were 1.92, 3.00, and 5.42cm.
The average particle velocity, U_p, calculated by the local values of particle concentration and velocity, was correlated with modified Froude number and particle Reynolds number based on the terminal settling velocity in a stagnant fluid with a standard deviation of 5.1 %: for vertical upflow,
U_p/(U_s)_av=exp(0.010 Re^0.40_p)-0.0059 Re^0.69_p[(U_s)²_av/{D_Tg(ρ_p/ρ_w-1)}]^-1/2
for horizontal flow,
U_p/(U_s)_av=exp(0.016 Re^0.36_p)-0.24 Re^0.22_p[(U_s)²_av/{D_Tg(ρ_p/ρ_w-1)}]^-1/2
4<Re_p<540, 2<(U_s)²_av/{D_Tg(ρ_p/ρ_w-1)}<120, m_d<0.05
where (U_s)_av is average slurry velocity, D_T is tube diameter, ρ_p and ρ_w are particle and liquid density, respectively, and m_d is delivered concentration of particles.
The laser methods, one for the local concentration and the other for the local velocity, were successfully adopted as more convenient techniques for getting precise information on the behavior of particles than the conventional photographic method.