By popular demand, this a larger copy of the flow table mentioned in the Open Pipe Flow Measurement Method post.
Small Hydropower & Micro Hydropower
Your Online Small Hydroelectric Power Resource!
Using PipeFlow®-Expert – For Penstocks & Hydro System Pipelines
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SmallHydro’s Review of -
PipeFlow-Expert with a few Screenshots of Flow & Pressure Calculations
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PipeFlow® Expert - Used to design and analyize Penstocks & Pipes In Hydro Systems.
A number of you readers have commented that you needed a better understanding of your Hydropower penstocks or hydro system pipelines. Some have remarked “that was fast” when a quick and accurate estimate was returned.
In this short review I’m letting you in on my secret, I use PipeFlow-Expert® by Daxesoft to make these initial penstock performance and energy loss design estimates. It is a cycle of trial & re-trial to find the sweet spot for a hydro site. A design spot between power ROI and the sites infrastructure costs. These hydro capital costs include; electric switchgear, turbine and penstock costs, etc. Hint – the penstock and associated hardware are often one of the most expensive components in a hydro system.
Penstocks also can pose a hidden system operational expense in lost hydro energy $ value. When improperly designed, they can also have a long term risk to system integrity and safety issues as well. You can see that it is vital to get the penstock design right as early as you can. Until you get the penstock and hydro turbine design nailed down the whole hydro project is at risk.
For a more detailed and accurate hydropower system penstock analysis I use the same software with a more detailed input model. The design results for this tool are amazing and the tool is quite simple to set up and operate too. Maybe even fun, Ok I can hear you – Now Jess don’t get carried away… ;-)
I’ll just have to post you some videos showing how I use it.
This software has a great graphical interface with tabular data where it makes sense and a great fluid modeling and analysis engine to crank out your solutions on the double. Warnings and quick fix diagnostic pop-ups lead you to suspected areas within your proposed Penstock and pipeline designs that would cause either a very expensive failure or costly rework at a later time. PipeFlow Tools are worth gold to a hydropower system designer or site prospector.
But wait! Before you cart your Penstock over to their site, look at the special offer we have arranged for you first…
These screenshots are just a few of the many Hydro System relevant features of the PipeFlow Expert software. I chose them based on your Hydropower Penstock evaluation needs. For our current SmallHydro PipeFlow tools offer; See our Penstock Tools & Special Offers page.
After getting our special code, visit the PipeFlow site for more details on the different Penstock & Pipeline evaluation tools. I use these tools often while looking at overall Hydroelectric system efficiency and Hydro ROI $ optimization. Note: Make sure you Get your SmallHydro Savings Discount coupon here first
PipeFlow® Expert is by far the Best tool I’ve used of for Penstock Pressure & Flow efficiency evaluations. If your system is simple enough they even carry a less expensive ”Lite” version that will cover just a few pipes, valves and fittings for a real savings.
Of course everything PipeFlow makes has an instant Free download! So you should certainly try it before you buy it with this free limited capability trial version. You’ll need to get our discount offer codes first though, to get your special SmallHydro discount savings applied later if and when you choose buy. Check with PipeFlow for all applicable terms and conditions.
Click on an image or link below to enlarge the details of the screenshot image. There are more od these features and worked examples described on PipeFlow’s site. Just get your SmallHydro Promo Code(s) first!
 Pipe Flow Expert - Systems pipeline & penstock drawing tool details
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Pipe Flow System Drawing Area
Design, build, view and edit your system model with Pipe Flow Expert’s powerful and easy to use interface. The drawing area will let you define tanks, pipes, fittings, valves, pumps, components, flow controls and demands. |
 Hydro Turbine & Pump performace curve graph
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Pump Characteristics & Curve Data
Define a pump as a curve of flow versus head produced or as a fixed flow rate pump. Pumps can be saved and loaded independently to make it easy to copy and duplicate pumps as required. |
 Pipe Flow Expert - Unit selection window - allows custom Hydropower unit settings
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Configure Pipe Flow Units
Choose the units that you want to work in for each field type. The units can all be set to metric or imperial on mass, or can be configured on an item by item basis as required. |
 PipeFlow Expert System Fittings database
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Pipe Size & Materials Database
Choose from a database of standard pipe materials and standard pipe sizes for that material. New pipe material and size data can be added to the database as required. |
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PipeFlow Expert System Fittings database
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Pipe Fittings Database
Choose from our database of fittings information to add fitting information onto pipes. New fittings data can be created by the user and stored in the fittings database. |
Just add water!
SmallHydro,
Jess
“How can we help you connect the drops?”
Your comments & questions are always welcome!
Here’s some questions from Ben, one of our Small & Micro Hydropower Newsletter readers. He asked these questions regarding turbine sizes, efficiency and penstock design.
Sincerely,
Jess
Hydro System Design Questions:
——– Original Message ——–
Subject: turbine size
From: Ben
Date: Thu, June 11, 2009 8:16 am To: jess.blog@smallhydro.com
Jess,
- Was wondering, does a smaller hydro propeller, ( not sure of terminology) add rpm’s thus giving more electric production?? If so, what is a general increase??
- Also, in the formula you sent me about converting to psi, how can you increase the effeciency rating of 72%, in general terms???
- Finally, on the penstock, how much do you typically decrease the intake from the main water line?? In other words, with a 4″ line is the penstock intake 4″ or does it decrease to 3″, and what if you decreased it to 2″ penstock intake?? Will that increase the flow pressure and what impact does it have on spinning the turbine?? I still don’t have specifics but working on it.
Thank you,
Ben
Hi Ben,
Looking at your questions I’ll try and answer them the best I can. Turbine deisgn and choice is complex and efficiency of hydro design is also. Mixing both in one response is a great simplification. With that said here are my Answers.
Jess
Hydro System Design Answers:
- Choosing Smaller or larger propeller or water wheels is not the issue. Fluid flow over the hydro generator propulsion device gives rise to rotational motion. Rotor specific speed is the issue you refer to and different designs have higher or lower specific speeds due to the physics involved with that wheels geometry. That is the rotational speed of a rotor of one design compared to others will be higher or lower depending on the actual design or geometry involved regardless of scale. Specific speed is a comparative “unitless” number much like a Mach number is used for supersonic flow. Specific speed often stated something like this “ηs= η/η0″. Efficiency at a given flow/pressure regime depends on this number a lot. Enough on that topic for now. What a smaller diameter wheel (using a pelton wheel for example) does is imply that for a given water jet velocity they must spin at a faster rate to produce their optimum power output. Max Pelton efficiency is at about 47% of the water jet velocity. This speed maximizes power output for given a pelton impulse design. So with all other factors being fixed the wheels pitch or diameter will increase rotational speed to keep the center line of water impact moving at the same 47% linear speed of the water jet. Power will be about the same, but generator frequency will change with rotational speed which may make a speed reducer/increaser a requirement.
- Increasing hydro system %efficiency is a complex art, starting with intake and Penstock friction, then turbine choice & performance curve optimization, combined with inlet valve and draft tube design if required, then any speed transmission or reducer friction, next will be generator/alternator efficiency, finally the transmission losses including wires, transformer/inverter systems. The 72% efficiency example I give is a very simple average of a model 85% turbine x 85% geneator/transmission output. Mileage for your site and turbine choices will vary. The more accurate you make your hydropower model the better the result will be. You will be modeling power production and loss until the first water flows through the system, then you get your course grade based on how close your “Real/Model” score approaches 100% of actual results.
- The last part of your request has more to do with jet design and penstock friction. Typically the penstock will be much larger diameter than the jet intake. The pipe friction means that there is a large dynamic head loss over long distance flows. The jet or turbine intake design then takes the pressure drop and accelerates water through the intake throat, a much smaller distance. These cross sectional intake areas are much smaller on higher head units like pelton and turgo units vs. lower head pressure ones like Francis, PAT and Kaplan/Popeller ones. That’s part of why the low head turbine prices rise so rapidly with flow rate, there’s a large opening to a much larger volume of machine for the same output power. Generally you should seek to keep penstock intakes and penstocks free of friction loss, then reducers at the turbine may be possible if required. For example a PAT I know of takes a >30inch diameter main and necks it down to 10inches right at the PAT input valve. The overall system efficiency is just a part of the equation, remember those big penstocks cost big bucks so make sure you balance the equation for optimum water power system ROI$.
I hope this helps clarify things,
Sincerely,
Jess
DoradoVista, Inc.
PS. I plan to post this set of question/answers on the Blog OK? Generic name & content only.
Ben replied,
Use the question, so far I am 2 for 2 in getting my questions in the blog. Batting a thousand here.
Thank you for the answers.
Ben
You’re welcome!
Jess
The following diagram depicts DoradoVista’s twelve steps to evaluate a Small or Micro Hydropower site. As mentioned last month we will be covering each of the twelve evaluation steps in more detail as we update our Small & Micro Hydropower posts. Again please add comments or questions to each post so that we can address your needs more adequately.
12 Step Small & Micro Hydropower Evaluation Process
Pelton Wheel – 350 kW
Drago’s Lightning
Hydro Prospector Jess
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How may we help you Prospect for Small & Micro Hydropower Resources?
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