I assume that you are concerned with a flow splitting rather than a
flow joining condition. This is a condition covered in standard
fitting loss tables. It depends on the type of fitting and which way
the flow goes. In the case of a Tee, the branch flow loss is 1 Q,
while the run (straight through) loss is 0.4 Q. Q is the velocity
head, or dynamic pressure, or the kinetic energy, cast as head.

 Q = 1/2 V^2/g

If you use V in m/sec g is 9.81 m/sec^2, if V is in ft/sec g is 32.3
ft/sec^2

Generally the only place a flow splits is at the turbine for the use
of multiple nozzles. It can be shown that if you use piping that is at
least 3 nozzle bores in diameter, then the losses are minimal.

A nozzle converts all of the pressure to velocity, so Q at the nozzle
exit equals the head in the nozzle piping. If the diameter of the
nozzle piping is 3x the nozzle bore, then the velocity (area scales as
diameter squared, and velocity is proportional to area) in the nozzle
feed pipe will be 1/9th the nozzle exit velocity. Therefore, Q which
is 1/2 the velocity squared will be 1/2 of 1/81 of the nozzle q which
is the head at the feed pipe. That means Q is 0.6% of the net head
(after penstock losses) in the nozzle feed pipe. Since typical loss
coeficients of Ells and Tees are on the order of 0.4 to 1.0, that
means you can limit the fitting losses in the nozzle pipeline to about
1% of net head by using piping which is 3x the nozzle bore.

  Joe

Hartvigsen-Hydro
http://h-hydro.com 


--- In [EMAIL PROTECTED], "simamkele" <[EMAIL PROTECTED]> wrote:
> Can any one help me on the theoretical derivation of the loss 
> coefficient in the piping bifurcations as i need it for
optimisation 
> of this power plant yet i cannot assume it as a constant, unlike
the 
> inlet losses,sudden contraction and expansion and the geometry of
an 
> unsymmetric also comes into play.
> If there are any manuals,books,internet site,software analysis or 
> pipe designers kindly inform me.




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