If the total effect produced in the system can be reduced to the raising of a weight, then nothing has crossed the boundary.
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The surroundings include everything external to the system,and the system is separated from the surroundings by the system boundaries.
The successive stages are normally arranged side by side along a horizontal axis, constituting what is called an“axial flow" turbine.
The speed of the flow of the fluid,which in steam turbines is produced by a fall in pressure of the steam from the boiler.
A turbine is a rotary engine which is driven by a stream of fluid (liquid or gas) directed on to the blades of the stator (定子).