Dave wrote:
> 
> Can anybody help me figure how many gallons per minute will flow thru
> both a 10 inch and 12 inch penstock that is 22 feet long that has a 6
> foot 8 inch head without any turbine? The penstock will have one 90
> degree bend and a 3 foot draft tube. I trying to determine what size
> will be ideal to replace the existing 8.25 inch penstock before i
> size a turbine that sizes the penstock. Thanx
>  

1. 
This now the fifth time since October last year that I advise the group that
SF Pressure Drop 5.0 [available at http://www.pressure-drop.com/] makes it easy
to do any pipe friction/pressure drop calculation imaginable. This includes
bends, fittings and various intake profiles. I find it a neat program and easy
to use after a little
practice.

It will also provide you with an understanding of which values need to be
specified and which don't. In the example given, flow rate cannot be calculated
because the pipe material (and hence the friction coefficient) has not been
specified.  

2.
Once head and open flow rate are known, then to a very good first approximation,
maximum hydraulic power is delivered to the turbine when the flow rate is
reduced to 57% of open flow.  This corresponds to a net head of 2/3 of the
actual head, with 1/3 of the head being lost as friction in the pipe and its
intake.

Regards,

Max Enfield
Planetary Power




------------------------ Yahoo! Groups Sponsor --------------------~--> 
Yahoo! Domains - Claim yours for only $14.70
http://us.click.yahoo.com/Z1wmxD/DREIAA/yQLSAA/FGYolB/TM
--------------------------------------------------------------------~-> 

Does your company feature in the microhydro business directory at 
http://microhydropower.net/directory ? If not, please register free of charge and be 
exposed to the microhydro community world wide!

NOTE: The advertisements in this email are added by Yahoogroups who provides us with 
free email group services. The microhydro-group does not endorse products or support 
the advertisements in any way. 

More information on micro hydropower at http://microhydropower.net

To unsubscribe: send empty message to [EMAIL PROTECTED] 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
     http://groups.yahoo.com/group/microhydro/

<*> To unsubscribe from this group, send an email to:
     [EMAIL PROTECTED]

<*> Your use of Yahoo! Groups is subject to:
     http://docs.yahoo.com/info/terms/
 

Reply via email to