Kaplan Turbine

Without knowing what your specific installation looks like and what access might exist around and to the area in which you wish to measure pressure there is no way that comes to mind except getting your pressure measuring device either inside the tube, or connected to the inside (as by small diameter tubing, through the wall or along the inside of the draft tube from its ultimate discharge opening) at the point where you wish to measure pressure.

Your information provides no clue even as to where the draft tube outlet is in relation to the propeller or the ultimate discharge opening.

Sorry I couldn't be of more help. Can you provide more specifics?

I must be very dull this morning as the solution seems so obvious: Drill and tap a hole in the draft tube and screw in a presure gauge. A photograph of the test rig would be helpful in suggesting an exact location

H H McDonald PE BSME

We knew what one was, but his is a demo, operated from a pump instead of installed in a waterway so we had no idea what his intallation looks like.

I don't see any connection to his question.

My previous reply was in response to a post that someone (whose name I will leave out) made that was a direct copy of an article on Kaplan Turbines from Wikipedia.

Apparently it was removed since it is no longer here and the reference to that post, in my previous post was also removed.

Since it was here for a time, I am assuming CR4 removed it over a "content ownership" issue. (?)

As the Kaplan is typically a low-head device, suitable pressure gauges may be difficult to obtain. Drilling and tapping a number of (say) 1/8" bsp (or npt) holes, fitting with glass or polycarbonate 'U' tube manometers (replace compression ferrule with rubber 'O' ring) will get a picture of the pressure (or suction) profile along the draft tube. A reasonable drawing of the device would, I'm sure, interest many of the contributors to this forum, and enable better suggestions. Cheers Greg Hall -

you can measure pressure in draft tube by just driling hole and insert(make brazing) nipple and use "U" TUBE menometer to measure pressure (it will be below atmospheric.)