Sphericity of Cylinder
Calculate the sphericity of a cylinder of dia 1 cm and height 3 cm.
Calculations:
Volume of particle = π rc2 h = π x 0.52 x 3 = 2.356 cm3
Radius of sphere of volume 2.356 cm3:
4πrs3 / 3 = 2.356
rs = 0.8255 cm
Surface area of sphere of same volume as the particle = 4 π rs2 = 4 x πx 0.82552 = 8.563 cm2
Surface area of particle = 2 π rc (h + rc) = 2 x π x 0.5 x (3 + 0.5) = 10.996 cm2
Sphericity (φ s) = 8.563/10.996 = 0.779
Sphericity could also be found from the formula,
Sphericity (φ s) = 6 Vp / (DpSp)
Where Vp = volume of particle
Dp = Equivalent diameter of particle. (Equivalent diameter is defined as the diameter of a sphere of equal volume)
Sp = surface area of particle
Vp = π rc2 h = 2.356 cm3
Dp = 2 rs = 2 x 0.8255 = 1.651 cm
Sp = 2 π rc (h + rc) = 10.996 cm2
φ s = 6 x 2.356 / (1.651 x 10.996) = 0.779