Problem # $2$

$[35$ Marks$]$

The figure below shows the basic dimensions of a radial$-$type centrifugal pump. The pump$-$out vanes on the back shroud are designed to balance the axial thrust when the pump operates at its rated capacity. However, at higher or lower flow rates there will be some residual thrust Determine the residual thrust for this pump when operating at a flow rate of $0\mathrm{.}08\frac{m^3}{s}$ at which the total head developed is $120$ m $.$ The other pump operating data is given below.

Pump speed, $N$

Pressure at the impeller inlet eye, $p_s$

Pressure in the volute casing, pvol.

$=2500rpm$

$=60$kPa $abs.$

$=1\mathrm{.}22$MPa $abs.$