turbine
turbine
(OP)
Please, what is by summary the main diference between reaction turbine and impulse turbine ,and how the pressure transferred to torque for both
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RE: turbine
What you ask is answered in several of the papers listed.
rmw
RE: turbine
RE: turbine
RE: turbine
RE: turbine
Best regards,
RE: turbine
RE: turbine
RE: turbine
RE: turbine
RE: turbine
You could refer to text, which give schematic and cutaways of turbines describing turbine design configurations. I trust this helps.
Best regards,
GTSIM
RE: turbine
RE: turbine
Buckets connote impulse where the pressure drop, hence the velocity increase, takes place in the stationary parts (diaphram) and the buckets 'catch' or try to 'stop' the kinetic energy of the high velocity steam, imparting torque to the moving parts (rotor).
In the USA, GE historically went the impulse route while Westinghouse turbines were principally reaction turbines. Reaction turbines tend to have more stages. Reading some of the GER's referred to in my first reply imply that GE has seen the light and is now advocating more reaction stages.
Also recognize that pure impulse and/or pure reaction stages are impractical, so each type of turbine contains some of the other. My comments only imply that the 'majority' of a stage ends up being impulse or reaction.
To my way of thinking, sakram seems to be mixing up some combustion turbine terminology and steam turbine terminology.
Sakram; lots of the questions you are asking are available in the GER's link that I referred you to in the beginning of this thread. Do you have the capability to open and read them?
rmw
RE: turbine
RE: turbine
RE: turbine
Imagine a stationary steam hose (nozzle) directed at a rotor with some water buckets attached to it.
In a reaction turbine, the stator parts are for not much more than to change the direction of the steam and redirect it into the next row of turbine blades which are essentially rotating nozzles.
Imagine a rotor with two jet engines mounted opposite each other, each producing thrust making the rotor rotate. Now change the jets to steam nozzles.
Most turbines use a combination of both, impulse and reaction, with one or the other being the predominant type. Some larger diameter stages are impulse at one part of the blade, and reaction at another part. As it changes, you can see the blades twist. The machines I have experience with have impulse at the root of the blade, changing to reaction at the tips. The first stage, however was typically pure impulse.
This is because of the relative velocities of various parts of the blade with respect to the stationary parts. The root area rotates at a slower rotational speed than does the tip. Since the 'impulse' on the bucket is dependent upon the relative difference between the speed of the rotating bucket and the nozzle exit velocity, at the higher tip speeds, the bucket may be moving away from the nozzle so that there is very little relative difference. Here the blade profile changes to reaction, since all that is important here is to get the steam into the blades so that it can expand and turn the rotor by the velocity 'reaction.'
rmw
RE: turbine
RE: turbine
Any remarks I made in recent posts above except the one where I noted that I thought sakram was mixing steam and gas turbine terminology were limited to steam turbines only. I didn't even put my gas turbine hat on just because of what you point out. Gas paths in CT's are a whole different discussion for just the reason you point out.
rmw
RE: turbine
Best wishes,
gtsim
RE: turbine
RE: turbine
RE: turbine
Buy a book! This is a forum to exchange ideas, not to get a complete foundation course in turbine design.
----------------------------------
One day my ship will come in.
But with my luck, I'll be at the airport!
RE: turbine
RE: turbine
Did you read any of the GER's in the link I posted in the second post of this thread?
If you go back to the base GER site, there are plenty of GER's on Combustion Turbines and combined cycle units too.
rmw
RE: turbine
RE: turbine
See if you can get to a better computer where you can download and copy the papers for your technical library. I did mine while I was the proud owner of Windows ME (does ME stand for Microsoft's Edsel?) and it was difficult for me as you have experienced.
But you will be glad you did if you can get it done. It is difficult for us as contributors to this forum to have to present all this information in detail that is already available if you can get it downloaded by some means.
rmw
RE: turbine
rmw