Shamlou's equation (Shamlou and Koutsakos, 1989) was modified to estimate the solid distribution in solid-liquid stirred vessels. alpha, X and Re-p was added in order to use a correlation equation widely (alpha: empirical constant, X: solid mass to liquid mass ratio, Re-p: particle Reynolds number). Peclet number for the solid was correlated by the following equation. Pe = alpha[N(p)(1/3)nd/u(t)X(0.13)(d/D)(2)(H/D)(-4/3)](-1.17) Re-p(-0.285) The value of alpha was 15.4 for radial flow impeller (disk turbine), 7.24 for mixed flow impellers (pitched paddle, pitched disk turbine and A310 (TM)) and 2.98 for axial flow impeller (marine propeller). Axial flow impeller with large d/D (D, vessel diameter; d, impeller diameter) was suitable for uniform suspension.