Please do not use the other available solutions as I have reviewed them and not been able to comprehend them. I ask for specific clarification on how to find the Mach number for the second part.

Consider an axial flow air turbine stage $($stator $+$ rotor rows$)$:

Given design parameters:

Mass flow $=1\mathrm{.}8k\frac{kg}{s}$

Use gamma of $1\mathrm{.}35$

Conditions at station $1($exit from stator or inlet to rotor$)$

Stagnation temperature $=627$degC

Stagnation pressure $=2\mathrm{.}9$ bars $($absolute$)$

Flow angle $=70$ degrees from the axial direction

Diameter at inner shroud $=0\mathrm{.}225m$

Diameter at outer shroud $=0\mathrm{.}275m$

Rotor peripheral speed at mean diameter $=0\mathrm{.}5x$ circumferential component of air

absolute velocity at station $1.$

$($a$)$ Calculate static temperature and pressure at station $1.$

$($b$)$ Calculate stagnation temperature at station $0($inlet before stator$).$

$($c$)$ Calculate static temperature at station $0($assuming that axial velocity is same between

station $0$ and $1$ and flow is axial at station $0).$