What steady flow process????

Steady flow process is a process where: the fluid properties can change from point to point in the control volume but remains the same at any fixed point during the whole process. A steady-flow process is characterized by the following:

No properties within the control volume change with time. That is
mcv = constant Ecv = constant
No properties change at the boundaries with time. Thus, the fluid properties at an inlet or exit will remain the same during the whole process. They can be different at different opens.
The heat and work interactions between a steady-flow system and its surroundings do not change with time.

Example steady flow process