Jet duct extention

[Olav]

Hopefully a not too stupid question for the fluid mechanics experts:

Assuming a typical waterjet drive as shown in sketch a) which is then extended by adding a cylindrical tube of the lenght "x" to where the nozzle with the stator blades used to be (sketch b) while the shaft is also lengthened so that the impeller will be located within the same distance to the stator and nozzle as before.



What kind of losses would you expect? There will be additional friction due to the longer duct of course - but anything else?

Many thanks in advance!

Edit: Should be "extension" in the title of course!

[anthony goodson]

Some of the larger PP JETS had a very long intake particularly the 210 but without the sharp angle you have drawn on the bottom of the entry,I don't know why, but Richard Parker certainly knew what he was doing

Regards Tony

[jim lee]

I can't see that it could help any. But I wonder why would you want to extend the entry portion?

-jim lee