$($a$)$ Determine the pressure drop in $cm$ of $H_{2}O$ at the onset of fluidization when catalyst particle having a density of $1\mathrm{.}8\frac{g}{c}c$ are fluidized with liquid petroleum fraction having a density of $0\mathrm{.}8\frac{g}{c}c.$ The static bed height is $200cm$ and the bulk density of the bed is $0\mathrm{.}96\frac{g}{c}c.$

$87$

$3$

$[$Turn over

$3$

$($b$)$ Derive the expression of maximum and average velocity in a circular tube.

$($c$)$ What do you mean by 'sphericity'? Find out the sphericity of a cylindrical particle.

$)=(3)=(3$

$($d$)$ Write the expression for

$($i$)$ Ergun's equation

$($ii$)$ Kozney$-$Corman equation.