A powder forms a bed in a small tube. The bed is 0.8 cm in diameter and 2 cm long. The density of the powder is 2.5 g/cm3 and 1.5 grams of powder was used to form the bed. Air (density 1.2 kg/m3 and viscosity of 1.8x10-5 Pa s) is drawn through the bed at the rate of 7.6 cm3/min. Under these conditions the pressure drop across the bed is 60 mm Hg. Determine the
a) porosity inside the bed of powder
b) superficial gas velocity in m/s
c) surface area per unit volume of powder in m-1 using the Kozeny-Carmen equation
d) Sauter mean diameter of the powder in um
e) modified Reynolds number