BOB: The setting of a pipe to reduce the sucking of debris into the pipe calls for setting the pipe well below the water level and the dispersion of the water suction effects.
Some of the solutions: making a large pond to keep the floating debris floating and not getting close to the inlet A slanted semi fine mesh wall feeding the pond, additional wall needs to direct the water in an angle away from the mesh wall to generate eddy currents to wash the debris from the mesh wall -- this unhappily depends on the terrain, the creek water level and depth of the water and each place needs careful observation to determine the best arrangement of the intake parts. The pipe intake should be expanded, we have increased the intake 20 to 100 times the pipe diameter area to reduce the sucking effects to a minimum. Mesh containers around the intake to stop small debris from entering the pipe, We have made the last mesh not larger than 1/3 of a Turbine Nozzle diameter to avoid clogging. We have installed more than one debris mesh wall, sometimes in a scaled diameter size for progressive debris size control.( 2 or 3 ) debris walls. Intake installation is not the last thing to do, it should be planned as one of the most important factors for a successful and long life hydro system. Debris mesh walls do not mean a wall but an arrangement of walls, containers, enclosures around the intake pipe. Weavers sense the escaping water currents in their ponds and run to clog those escape sites, so the water current into the pipe needs to be diffused in a much larger area before entering into the pipe for the weaver not to detect it, in some places the intake area needs to be incremented many times over and/or somewhat large mesh containers around the piping to keep the Weaver away from sending the "escaping water" and "drain holes". Regards Nando ----- Original Message ----- From: "Bob Boyce" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, August 03, 2004 1:12 AM Subject: [microhydro] MicroHydro question > I currently have a small (1.2 KW) PV solar array, and I am wanting to > add a homebrew microhydroelectric installation on my property. > > For a test, I laid about 80 feet of 2" PVC pipe in the creekbed with > a small rock dam at the head to collect water, and at the end I have > a 90 ell with a couple of feet of pipe sticking straight up to give a > bit of back pressure. I need to figure out how to deal with the > problem of leaves and twigs and such from plugging up the inlet. If > the weather is nice, it lasts a long time between cleanouts, but any > strong wind or hard rain and it plugs up rather quickly. During the > fall it was getting plugged up almost daily. I tried making a large > coarse screen bubble out of lathe mesh to filter the larger stuff > while allowing the smaller particles to pass, since they do not plug > the pipe, but the screen gets all plastered with leaves and blocks > the flow. I was hoping that the flow of the creek past this inlet > screen would keep it washed clear, but the pipe suction is so strong > that it does not work that way. Does anyone have any suggestions on > how to solve this issue. I have not decided yet which is the best > homebrew approach to take in order to extract energy from this moving > water. I do not have a lot of head to work with so it will have to be > something that can work with lower pressure, and won't cost a lot to > build. > > > Bob > > > > > > > > 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 > > > > > ------------------------ 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/
