Consider a process heating application where hot water is to be supplied. $0\mathrm{.}8$ kg$/$s of saturated water flows at $100$C through a horizontal pipe of $20$ mm diameter and $4$ m length, which is uniformly heated with a power of $100$ W$.$ The designer has used homogeneous model for calculation of pressure drop for all purposes ahead of this pipe. Verify if the designer is right is assuming this to be assuming this to be a homogeneous flow. Suddenly the valve in the water pipeline mal$-$ functions and the flow rate drops to $0\mathrm{.}5$ kg$/$s$.$ See if the designer$$s calculations are still valid?