Working out steam velocity with only pressure difference

AI Thread Summary
To calculate steam velocity between pressure differences in a turbine, one must consider the energy extraction by turbine blades, which affects flow resistance. In a theoretical scenario with no resistance, the velocity can be estimated using the pressure change and specific volume at different sections. The steam transitions from overheated to sub-cooled conditions, impacting its properties throughout the turbine. A sudden pressure drop could lead to an adiabatic expansion, resulting in variable steam speeds across different cross-sections. Understanding these dynamics is crucial for accurate velocity calculations in turbine systems.
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I am currently doing an assignment on nuclear power and in the turbine, the steam is moving from pressure of 6Mpa to 0.008 Mpa. is there any way to work out the velocity of the steam when moving between these pressure differences?
 
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Welcome! :)
The main reason you have that pressure differential is the blades and rotors of the steam turbine, which are stealing energy from the steam flow: therefore, that steam velocity at each section depends on that internal resistance to the flow.
 
Lnewqban said:
Welcome! :)
The main reason you have that pressure differential is the blades and rotors of the steam turbine, which are stealing energy from the steam flow: therefore, that steam velocity at each section depends on that internal resistance to the flow.
Thanks for your response!
How about if the system was treated as having no resistance to flow to work out a theoretical maximum velocity would there be a way to do this?
 
A change of pressure is involved for the mass of steam going through certain cross section; therefore, the specific volume at each section should be considered.
The conditions of steam could go from over-heated steam (turbine inlet) to sub-cooled condensate (turbine outlet) in a real turbine.
In your hypotetic case, the sudden pressure reduction could imply a sudden adiabatic increase of volume; resulting in a variable speed of steam for each cross-section of what would now be a duct rather than a entalphy degrading machine.
 
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