Capt_Cully
Active member
So do penductors add head pressure?
Penductor Question
- Thread starter Capt_Cully
- Start date
captain7359
Active member
Yes, a good bit. you are restricting the flow down through a 0.3" orifice. Think about how much 1/2" pvc restricts flow and then go smaller for the penductor.
http://www.kthsales.com/website/Misc/Low pressure eductor flow rates.pdf
Take a look at the Goby pump running at 12' of head loss. It will put out 2080gph(35gpm). The 0.3" penductor will flow 5 gpm, but you would need to put in 7 to get the 35gpm pump output. Total flow in the tank would be 7x25gpm through the penductor for a total of ~10500 gph. You could run 3 of the 0.375" penductors to get a flow in the tank of ~9000 gph or just 2 of the 0.48" ones to get ~9100 gph. at 12' the goby pulls 210W so you're less than 2A and would run you about $0.40 a day at $0.08/kWh.
Just remember if you are pumping from a sump that you have to add in the head loss of the piping and vertical height to get the "real" head seen by the pump. I ran the numbers above with the pump as a closed loop and didn't factor in any piping losses.
Capt_Cully
Active member
I crunched the numbers using the head loss calculator on the home page and I always seem to be between 6 and 8 ft of head loss. This is, however, WITHOUT accounting for the penductors.
Pump will have 5 feet of vertical, 3 feet of horizontal. 2 45's, 1 90, ending at a T with locline into the 2 penductors listed in the Aquacave link.
I'm not so concerned about the flow I get out of them. I was just looking to optimize a little bit of flow as my primary concern, is energy conservation, i.e. cheaper operating costs. My main flow, will be supplied by 2 Vortech MP40's on the back wall. The penductors were for surface aggitation and to keep the flow across the surface, or top few inches, back toward the overflow.
The snapper would use about 100W. Flow at 7' is 1500 GPH, 9' is 900 GPH drawing 95W. It drops off sharply after that to 300 GPH @ 11' drawing only 70W, but that wouldn't be what I'd want.
SOOOOO, the question is HOW MUCH head do those penductors add on? They are the 3/4 inch models. Narrowest portion of restriction, is 1/4 inch.
Plumbing sizes would vary exiting the pump, depending on model. But horizontal run would likely be 1" or 3/4".
The Snapper pump could be sweet, but if my calculations are off, it could be a fart in a stiff wind.
Come on Walter.....whaddya got?
p.s. it's Daddy Daycare today, any suggestions for flavors this evening. I'll be shopping through the selection at The Weg. (IPA, more hoppy than sweet) You're the bartender.
Pump will have 5 feet of vertical, 3 feet of horizontal. 2 45's, 1 90, ending at a T with locline into the 2 penductors listed in the Aquacave link.
I'm not so concerned about the flow I get out of them. I was just looking to optimize a little bit of flow as my primary concern, is energy conservation, i.e. cheaper operating costs. My main flow, will be supplied by 2 Vortech MP40's on the back wall. The penductors were for surface aggitation and to keep the flow across the surface, or top few inches, back toward the overflow.
The snapper would use about 100W. Flow at 7' is 1500 GPH, 9' is 900 GPH drawing 95W. It drops off sharply after that to 300 GPH @ 11' drawing only 70W, but that wouldn't be what I'd want.
SOOOOO, the question is HOW MUCH head do those penductors add on? They are the 3/4 inch models. Narrowest portion of restriction, is 1/4 inch.
Plumbing sizes would vary exiting the pump, depending on model. But horizontal run would likely be 1" or 3/4".
The Snapper pump could be sweet, but if my calculations are off, it could be a fart in a stiff wind.
Come on Walter.....whaddya got?
p.s. it's Daddy Daycare today, any suggestions for flavors this evening. I'll be shopping through the selection at The Weg. (IPA, more hoppy than sweet) You're the bartender.
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110galreef
New member
Can you help explain this too me?
I am planning on a Super Dart Gold pump CLS. I will flow thru OM 4 way, so thus 2 outputs at a time. Of the 2 I plan to use an eductor on one at a time. I plan to go like 65/35 split regular outlet/eductor. How would i get a ballpark of what flow i would get? What type of head do I look at for the 1 eductor on the outputs? Assuming 8'....at 8' head Super Dart Gold flows 2440gph. 65/35 would get me like 1586gph thru non enductor & 854gph(~14.3gpm).
Now if I go with the .48 orifice 1" MPT enductor at the 14.3gpm & 10' of head shows the total of ~69gpm(4140gph). hat puts me at:
1586gph thru non enductor &
4140gph thru enductor for a total of 5726gph.....
compared to the CLS w/ just outputs split at say 2' of head total output is 3900gph. So for $50 i pick up 1826gph of flow! or a 45% increase of flow!
captain7359
Active member
To fet any sort of appreciable flow increase out of the penductors they reccomend 3.5psi(8') at their inlet. With the ~7' of loss from your piping that puts you up to 15' required to do any amount of decent flow increasing. In actuality you'd end up between 7' and the end of the pump curve, but the penductors wouldn't be making up for the steep drop in pump flow out at the end of the curve. The snapper is flow biased and I'd keep as much restriction off it as possible and go up to 1.5" or even better 2" piping for as much of the distance as possible. With 2" your flow goes up to over 1600gph and only 105W or so. The power curves on theflow biased pumps are pretty flat so any flow reduction doesn't really help in energy savings that much. The pressure rated pumps can benefit a bit more from tuning them to their sweet spot and have more pressure to play with. The goby at 7' piping loss and 8' penductor loss still gives you 1400gph(23.3gpm) and could run 2 of the 0.48" penductors to give you ~7400gph in the tank, but at 200w. I'd say if you want to stick with a snapper give it as much free flow as you can with big piping. If you want a lot of in tank flow use the pressure rated pump and the penductors.
http://beeradvocate.com/beer/profile/321/27804
Yes, it's Belgian, yes it's a bit malty, yes it's still hoppy, but a Belgin kinda hoppy. Just something different to throw out there for ya. Otherwise Troegs Nugget Nectar is out now.
http://www.troegs.com/our_brews/nugget_nectar.aspx
Ypu've gotta figure out your piping losses alone. Then see what you have for pressure left available from the pump starting at adding another 8' for the penductor to see what kind of low you would have at piping losses + 8'. Take that flow and see how many of which penductors you could drive and multiple your flow. KTH will help you pick penductors if you give them a ring with pump specifics too. Depending on the OM model you have it may not like the backpressure on the ports and cause the drum to skip or bind in the housing. If you have flow going to 2 separate ports on teh OM at once you can't have a penductor on one of those and not on the other. The water will just take the path of least resistance and flow out the non restricted side mostly and only give you a marginal flow out of the penductor.
Gary Majchrzak
Team RC
fwiw
fwiw
I thoroughly researched using penductors with an OM.
Paul @ OM emailed back and forth with me regarding the combo.
John T. (drtango) tried it. Long story short: don't do it. Backpressure will cause the drum to fail.
If you choose to ignore this advice you should choose to run all returns with penductors or none at all.
As far as I know penductors require a pressure rated pump. If the pump isn't pressure rated you gain little to nothing by using penductors except some big ugly nozzles.
fwiw
I thoroughly researched using penductors with an OM.
Paul @ OM emailed back and forth with me regarding the combo.
John T. (drtango) tried it. Long story short: don't do it. Backpressure will cause the drum to fail.
If you choose to ignore this advice you should choose to run all returns with penductors or none at all.
As far as I know penductors require a pressure rated pump. If the pump isn't pressure rated you gain little to nothing by using penductors except some big ugly nozzles.
Gary Majchrzak
Team RC
Capt_Cully
Active member
I'm definitely going to experiment with them, but I'm in the lucky position that i'm not commited to them. It would be nice if i can get them configured under a low energy consumption lay out. To reiterate, that's the goal.
If they do not end up being effective, I can simply change or institute a traditional return and loc-line set up.
Can you guys elaborate on what exactly a "pressure rated" pump, or other brands might be. (Sequence/Reeflo's have already been discussed)
If they do not end up being effective, I can simply change or institute a traditional return and loc-line set up.
Can you guys elaborate on what exactly a "pressure rated" pump, or other brands might be. (Sequence/Reeflo's have already been discussed)
Gary Majchrzak
Team RC
Walter might be better at explaining this but (basically) a pressure rated pump pushes harder when backpressure is applied.
I'm not sure if energy consumption is affected in such applications.
Iwaki, Panworld, Little Giant are just some examples of pressure rated pumps that come imediately to my mind.
I'm not sure if energy consumption is affected in such applications.
Iwaki, Panworld, Little Giant are just some examples of pressure rated pumps that come imediately to my mind.
110galreef
New member
Ok so on a CLS, lets just assume 3' head loss due to the plumbing. Talking to KTH, they said the eductors put minimal pressure on the pump. I aksed 2-3' additional, & they said that sounds about right.
So would I take 6' of head (3' from plumbing + 3' for penductor) to figure the flow of the pump...ie ~2800gph @6' head, then go say 70/30 split between outlets (1960gph & 840gph (14gpm). Then the pump has a max head of 13'.
So if I look at the .48 orifice at 12' head & my 14gpm then that equates to the 69-75gpm flow. 4140-4500gph Am i doing this right now?
Also if the eductors only add like 2-3 feet of head, and the new mag drives on the OM should handle this minimal extra pressure. If it fails, then a simple drum swap or motor swap can be made. I can pull the drum very easily after a month & see what it looks like to see if any damage is occuring. Or just be sure that the two oppsing port have the same eductors or regular outlets to be sure the drum pressure is evenly distributed.
Again if I can pick up ~low 6000gph now out of a 4300 gph pump and burn up a drum year....I'm down!
110galreef
New member
KTH sales sounds like I will still get a significant increase in flow with a pump as long as it can handle at least 10' head.
But for the cheap cost to TRY it i am for it. I know I have done a eductor before on a friends tank & he had a simple submersible pump and he got atleast double the flow out of it. Had to definitly cut the flow back as it was a lot more than he previously had.
captain7359
Active member
Gary's got the basic function of it. The impeller pushes the water harder in a pressure biased pump, but it also requires more power to do more work.
Here's two little giant 4 impellers
The flow biased impeller has fewer larger flutes
Compared to the pressure biased impeller with more smaller flutes
To get the right pump you normally design your piping system, then pick the pump (impeller, impeller trim, and motor power) that gets you the flow you want at the pressure required to overcome the friction created by the water flowing in the pipe and the height the water is lifted to.
Looking at power, flow, and efficiency all on one curve
http://seniordesign.engr.uidaho.edu/2009-2010/iheat/Solution/PumpCurve.jpg
Here, make your head hurt like mine does every day with this fun stuff...
http://kb.eng-software.com/questions/7/Minimizing+Pumping+Costs
mr.maroonsalty
New member
I didn't want to beat my brain over the pump the way I did the skimmer, and went with the snapper hybrid pump incase I decide to up the flow.
iamwrasseman
New member
Mark they have a panworld 100ps over at ABC that is very reasonably priced and it may be what your looking for . check it out
Not to hijack your thread fellas, but if I may join in...
I am also currently looking to design and implement (my first) closed loop that will be for my 60g cube. I have no experience with eductors/penductors or how to choose the right pump for the application... Is there any formula for how to determine number of penductors per loop/pump? I have an extra Quiet One 3000 not being used (rated @ 780gph, 0' head) and wondering if this pump with, say, 4 penductors in my 60g cube would provide ample flow/turnover rate?..
Based on what has been stated above, I do not believe this pump is a "pressure rated pump" but I am planning to drill the bottom of the tank for drain & return so head loss for my application will be very minimal (the footprint of the tank is 24" x 24" and the loop will obviously not extend the full spread because I plan to conceal all piping with rock formations). But if penductors can increase the output by 4-5x, am I mistaken in thinking I can achieve ~3,000gph turnover with the above application? Additionally, what size penductors should I use? (I am thinking 1/2"?)... And how many outputs for my loop? (I am thinking 4, maybe 6?)
Any help you can offer to better guide me in this area is greatly appreciated.
I am also currently looking to design and implement (my first) closed loop that will be for my 60g cube. I have no experience with eductors/penductors or how to choose the right pump for the application... Is there any formula for how to determine number of penductors per loop/pump? I have an extra Quiet One 3000 not being used (rated @ 780gph, 0' head) and wondering if this pump with, say, 4 penductors in my 60g cube would provide ample flow/turnover rate?..
Based on what has been stated above, I do not believe this pump is a "pressure rated pump" but I am planning to drill the bottom of the tank for drain & return so head loss for my application will be very minimal (the footprint of the tank is 24" x 24" and the loop will obviously not extend the full spread because I plan to conceal all piping with rock formations). But if penductors can increase the output by 4-5x, am I mistaken in thinking I can achieve ~3,000gph turnover with the above application? Additionally, what size penductors should I use? (I am thinking 1/2"?)... And how many outputs for my loop? (I am thinking 4, maybe 6?)
Any help you can offer to better guide me in this area is greatly appreciated.
der_wille_zur_macht
Team RC
FWIW there's really no such thing as a "pressure rated" pump. All pumps work against head pressure, it's just that some are designed to create lots of flow at low pressures (and will do poorly at high pressures) and others are designed to create a moderate flow at a high pressure (and will be a waste with low pressure).
Pressure is essentially determined by the load you hook the pump to - it comes in two flavors, static head (the vertical distance a pump has to lift the water, which is zero for a closed loop) and frictional losses, which are typically divided into major losses (friction per unit of pipe length) and minor losses (friction due to turbulence around elbows and other fittings).
If you know the total pressure your system design will place on a pump, you can look at flow curves for different pumps and determine how much flow you'd get from each of them at that pressure. Part of the problem though is that frictional losses are dynamic, i.e. they change as flow rate changes. The head that an eductor adds will be different at different flow rates.
because of this it's sometimes common to approach this "backwards" i.e. find a pump, assume a certain baseline pressure (from static head and major losses) then determine how the pump would react to a certain number of eductors based on the flow it'll produce at various pressures above that baseline.
KTH publish a lot of really awesome info on doing all this math but unfortunately they only include data and "rules of thumb" for the eductors they sell. I have never seen solid info on the eductors sold elsewhere in this hobby, which is a real shame, since it means we're really just guessing at their performance.
I started a thread a few weeks ago asking for specs on the hobby-oriented eductors and didn't get much of a response. Somehow I missed this thread so I'm glad it came back up.
Pressure is essentially determined by the load you hook the pump to - it comes in two flavors, static head (the vertical distance a pump has to lift the water, which is zero for a closed loop) and frictional losses, which are typically divided into major losses (friction per unit of pipe length) and minor losses (friction due to turbulence around elbows and other fittings).
If you know the total pressure your system design will place on a pump, you can look at flow curves for different pumps and determine how much flow you'd get from each of them at that pressure. Part of the problem though is that frictional losses are dynamic, i.e. they change as flow rate changes. The head that an eductor adds will be different at different flow rates.
because of this it's sometimes common to approach this "backwards" i.e. find a pump, assume a certain baseline pressure (from static head and major losses) then determine how the pump would react to a certain number of eductors based on the flow it'll produce at various pressures above that baseline.
KTH publish a lot of really awesome info on doing all this math but unfortunately they only include data and "rules of thumb" for the eductors they sell. I have never seen solid info on the eductors sold elsewhere in this hobby, which is a real shame, since it means we're really just guessing at their performance.
I started a thread a few weeks ago asking for specs on the hobby-oriented eductors and didn't get much of a response. Somehow I missed this thread so I'm glad it came back up.
