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Human-powered impellar pump question

Human-powered impellar pump question

Human-powered impellar pump question

(OP)
I am part of a humanitarian group which is designing an irrigation pump for farmers in Malawi.  The pump itself is powered by an individual pedaling a bicycle, where an additional chain is connected from the rear bicycle gears to a gear around a shaft (a few feet behind the pump).  The shaft then rotates and in turn powers an impellar pump which pumps the water through a hose (impellar is a propellar designed for water that as it turns pumps water).  

Does anyone know a company that designs impellar pumps that work with the low power input of our device (approximately 1/8th a horsepower)?  Most pumps that I have found are designed to be used in conjunction with a motor which has a much higher power output and in turn much higher rpms than are possible from our human powered device.  

Any help is appreciated, thank you.

RE: Human-powered impellar pump question

My suggestion is to look at the World Bank website - you might find something of use there.

RE: Human-powered impellar pump question

bd,
I hope this post is only a joke (of a bad taste). I would however, suggest to buy an irigation pump driven by a small diesel engine.

RE: Human-powered impellar pump question

gr2vessels

If you haven't been to that part of the world, you may not know that simply getting the additional chain for the bicycle gear is a major feat.  

There is no diesel supply, tools, money or skills to buy, install and maintain a diesel pump.  Working in this part of the world at the moment, I can assure you the post is not in gest and the man is looking for a solution to a real problem.

bd103dall

As far as company's that supply those - you might try Northern Industrial or Grainger.  Grainger has a nice catalogue on line.

Greg Lamberson, BS, MBA
Consultant - Upstream Energy
Website: www.oil-gas-consulting.com

RE: Human-powered impellar pump question


bd103dall

I had a quick look at the World Bank site for you but couldn't come up with anything but I'm pretty sure they would have some info' somewhere on their site or at least a lead for you to follow, however, I have located the following link - this could well be what you are looking for and at least it's a good start for you.

http://www.makezine.com/blog/archive/2006/07/playpumps_kid_powered_merrygor.html

RE: Human-powered impellar pump question

I realise you asked about impeller design for your application and after thinking about it for awhile it is not really a great problem - you can use a small diameter axial flow or mixed flow impeller of 2 or 3 inch diameter to give you a low flow and head within the power rating of 1 or 2 people -unfortunately I can not give you a manufacturer, although any manufacturer making small diameter borehole (well) pumps could have something suitable and would be well worth contacting.
  

RE: Human-powered impellar pump question

I'd use one of those positive displacement pumps with the rubber star vaned impeller.  I'd feel bad wasting so much of the effort of a well intentioned slow pedaler with a centirfugal

RE: Human-powered impellar pump question

Positive displace pumps would be better.  If you only have 1/8 HP, then at 50% effiency you get a net 1/16 HP with centrifugal pumps.  With positive displacement you'll get 95% of the 1/8 HP.  A screw pump would be an example.

By the time you find or design a pump that will do what you want, you could buy a 24 volt DC pump off the shelf.  Then getting a generator afixed to a bike would be easier.

RE: Human-powered impellar pump question

I worked on a similar project years ago.  I'll try to contact the guy that I worked with.
These projects are a real engineering challenge.  Take a product that is available in the developed world for $100, then re-design it so that it can be made for $20, and then figure out how to do the same job for $5.
These pumps only need to last for a year.  You can help a couple of farmers increase their yields enough to have more food and to pay for them.
I recall seeing a treadle pump, this might be a basis for you.
http://www.ide-india.org/ide/treadlepump.shtml
http://other90.cooperhewitt.org/Design/bamboo-treadle-pump

= = = = = = = = = = = = = = = = = = = =
Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net

RE: Human-powered impellar pump question

It would help if you provided the required flow rate and the pressure it must pump against.

RE: Human-powered impellar pump question

I think that trying to use a centrifugal (impeller) style pump for something human powered will probably not turn out to be too effective.  I would suggest that you look into the old style plunger pumps, they would probably be more adaptable.

RE: Human-powered impellar pump question

In the old days, Archimedes had a pump that was turned by hand, animal and etc. You build it up as large as the power source available to turn it - or even better, put 2 or more in parallel to match the available power.

PD pumps, centrifugal pumps, and other modern day design really isn't a good fit with human power. Look back into history. If it was good enough for the Greeks, it should be good enough for most applications today, given the same "category" of technological advancement.

"Do not worry about your problems with mathematics, I assure you mine are far greater."   
Albert Einstein
Have you read FAQ731-376: Eng-Tips.com Forum Policies to make the best use of Eng-Tips Forums?

RE: Human-powered impellar pump question

a archimedes screw is a good option for this application. but for a more up to date solution. i have just done a course at the poul due jensen academy and grundfos have a bore hole pump that can be ran from solar power, wind turbine and they have an test rig set up in the academy to run from a bike. this pump is a sp type pump with perminant magnet motor best to look on there wed site under webcaps and it will spec the pump you require.

RE: Human-powered impellar pump question

All the high tech. knowledge and solutions are ok - but bear in mind what GregLamberson had to say (below), he is spot on with his comments - the OP wants a cheap, basic minimum maintenance easy to install and operate solution.

I agree with Ashereng as to the benefits of an Archimedes style pump but even this could be cost prohibitive in this situation as they are fairly expensive to manufacture.   

"GregLamberson (Petroleum) 23 Oct 07 3:53  
gr2vessels

If you haven't been to that part of the world, you may not know that simply getting the additional chain for the bicycle gear is a major feat.  

There is no diesel supply, tools, money or skills to buy, install and maintain a diesel pump.  Working in this part of the world at the moment, I can assure you the post is not in gest and the man is looking for a solution to a real problem."
 
But so far we haven't heard anything back from the OP so maybe he has solved (hopefully) the problem

RE: Human-powered impellar pump question

the pump i am talking about needs no diesel it runs on very low voltsge and can be powered from a bike but if the option of going to wind poweter or solar power was there i would take it. look up grundfos sq solar wind these pumps are the future

RE: Human-powered impellar pump question

There is no argument that the Grudfos pump is a good unit and ideally suited in areas where they can be afforded - however, having been involved in aid projects such as this, the OP is looking for something that can be built locally with minimum labour skills for a few dollars.  

RE: Human-powered impellar pump question

Gents,
I applaude the strive to provide the best engineering solution to the PO request. I have, however, serious reservations over the whole issue and the morality of it. We are looking in the wrong direction, is not the PO who counts, is the bunch of starved people, who need a "new pair of pants", not another "patch" on the old one. As such, I refuse to give any ideas to the PO, who ultimately harm the people intended for help.
Can anyone in this forum build an unmanned pumping station? Let's put a "buck" where the mouth is and send one to Malawi, present from this forum!
Howzat?
gr2vessels

RE: Human-powered impellar pump question

gr2vessels (Mechanical)

I fail to see how ever "primitive" the equipment that is required to do this job can be considered as immoral and what would constitute reservations to actually curtail any useful input.

If sending money makes you feel good - go right ahead and send some, however, what is probably of more use in this situation is advise in how to solve the problem as requested.
For me, I am trying to contact someone I worked with over 20 years ago who could have the solution to the OP request and if this turns out as I hope it will - I will be more than happy to pass this information on.

RE: Human-powered impellar pump question

The "best available technology" is very often NOT the best fit with solving the problem at hand when taking into consideration things like parts availability, local economic constraints and other miscelaneous cultural factors.

Examples:  

1.) Put too much copper wire out there and it all disappears or requires such an investment in security that it rivals the capital cost of the equipment it protects.  

2.) Somebody contributes 15 Solar cells that get installed in series.   Because its high voltage, the word goes out for a motor.  A 220 VDC comes in.  Requires switchgear that costs as much as a half the pump cost.  One blows and the locals wind up with a major HSE issue when they have to hold the wires together by hand.

3.) Can't get replacement part X?  Pump continues to run with vibration and next week they need a whole new pump.

4.) Pump gets "misplaced" at the port of entry.

Archimedes invented his pump for the very same reasons that either still exist today... or are much worse.

http://virtualpipeline.spaces.msn.com

RE: Human-powered impellar pump question

Forgot #5,

Village buys expensive imported seeds to take advantage of new high capacity pump and plants 100 hectares seeds and land purchase financed by local bank.  Pump fails, crops fail, bank fails, village starves.

http://virtualpipeline.spaces.msn.com

RE: Human-powered impellar pump question

In an issue of the Water Well Journal there was an article on a human powered pump.  They have a merry-go-round attached to it and the kids do the pumping while they are going round and round.  It pumps up to an elevated tank.  I cannot find the article this morning but, am still looking for it.

RE: Human-powered impellar pump question

Biginch, that' it.  Sorry I missed it on your post.  As usual you are just one step ahead of me.  Thanks

RE: Human-powered impellar pump question

I stand corrected and entertained.  I like the worm.

RE: Human-powered impellar pump question

Seems I get the worm - 23 Oct 5.55

RE: Human-powered impellar pump question

Half the time you get the worm 'cause you're 12 hours ahead of most of us.  (i.e. The rest of the time you're 12 hours late.) smile

http://virtualpipeline.spaces.msn.com

RE: Human-powered impellar pump question

[no evil]

RE: Human-powered impellar pump question

noevil

RE: Human-powered impellar pump question

What about a "standard" sucker rod pump (i think thats what they are called but ist similar to those used on oil wells and in "old hand operated" pumps.

The challenge would be to convert the movement of the chain (or belt) to a vertical movement - but that could be acomplised the same way as they do in oil fields.

Best regards

Morten

RE: Human-powered impellar pump question

How about an Australian windmill that turns with the wind and is connected to a basic single piston type pump drawing water up?

RE: Human-powered impellar pump question

cost , cost, and cost is the number one influencing factor followed by basic simplicity of operation and maintainence.


To bd103dall (Mechanical)

Are you still with us? As I have a few questions for you.  

RE: Human-powered impellar pump question

(OP)
Thank you everyone for your great input, there is a lot of information to look into, but I'll post again soon with further ideas and progress.  

I really appreciate the helpful suggestions.

RE: Human-powered impellar pump question

(OP)
Artisi,

I am still with you, feel free to ask me any questions you like.

RE: Human-powered impellar pump question

bd103dall (Mechanical)

A description of the site where you will use this pump/s would assist. Do you have any photo's you can post here.

What is the height from water level to the discharge point?

Are you pumping from a creek or similar to above the bank level, etc

I may well have what you need but need a bit more info from you as well as some more investigation on my part.

RE: Human-powered impellar pump question

(OP)
Artisi,

Those are some great questions your asking, and sadly I don't have any exact answers for you. We are currently working in conjunction with another group associated with the University of Malawi and are waiting on a response to a whole list of questions (several of which were similar to the ones you posted).  I believe we are mostly pumping out of a creek or similar open water stream to above the bank level.  As for the height of water level to discharge point, that will differ from site to site - we were hoping to design these pumps to be used in as many rural farming villages as possible.  In 90% of the cases, the elevation gain shouldn't be much more than 15-20 feet I would think.  Although I have not personally been to Malawi, so I don't know for sure (but will try to find out asap).  

I am very interested that you may have a solution to my issue, and I would love to further discuss any questions and concerns that you have.  Feel free to contact me at WaterCycleCo@gmail.com, I appreciate your interest and input so far on this project.

RE: Human-powered impellar pump question

I found this human power output chart over at,

http://www.howstuffworks.com/framed.htm?parent=question658.htm&url=http://www.ent.ohiou.edu/~et181/hpv/hpv.html

From that I derived this ideal PUMP CURVE to fit the human power output curve.  I don't think you'll find a pump with a curve like this one, but you could concentrate on finding a pump with good efficiencies in the 100 to 150 GPM range making a head of between 5 and 15 feet.  The different curves are for how long an average human can carry on outputing the required power to generate those heads.  Optimize the exact pump characteristics you need to specify by looking at the flowrate value and the pumping time you will allow befor an average human gets exhausted.

To find the volume of water that can be pumped by the average human, just multiply your flowrate by the allowed pumping time.

http://virtualpipeline.spaces.msn.com

RE: Human-powered impellar pump question

BigInch
Thanks for the last posting re human output against pump performance - very informative and useful.  However, the data you have found appears to be based on maximum output for a human whereas we need to be more conservative in the expectations.

I think in the situation for this application we would be happy with 4-5 l/m @ 5-6 m head something that is capable for 1 or 2 people working together for a few hours.
 
bd103dall
I will contact you with few more questions as this project is of interest to me as I am now retired with time on my hands and have some background in aid projects - although this has been at the top end of the spectrum where money wasn't a problem  with most of it going on consultants - but that's another story.

RE: Human-powered impellar pump question

I didn't know if the application was for drinking water or small scale irrigation.  These curves are for centrifugals anyway.  As was said above, a piston pump may be more appropriate.  They are power limited too, so easier to specify the correct cylinder size and strokes.

Find my e-mail in the contacts section of my webpage, drop me your address and I'll send you lower flowrate/higher head numbers at maybe half the power output.

http://virtualpipeline.spaces.msn.com

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