Backyard Aquaponics
A place to discuss aquaponics

Here is what my 0.5inch eductor looks like, with a crippled chick for scale.
The threaded end pushes snugly into 19mm low density poly pipe, which is handy.

I just read a wiki article in eductors, it looks like they could make airlift pumps more practical too.

I honestly think that there may be an eductor for every occasion, Ronmaggi!
See PMs, RupertofOZ.
I think I may have found your sexy curved eductors, Dave.
I saw a 1" version of my type of eductor and it was huge - like an early 1900s Klaxon horn! It must have been 25-30cm long. The curved ones appear more moderately sized.

Hi,

I would also interested in the derivation of the 1:4 ratio quoted.

Additionally, I would be interested in the increase in pressure/ lose of velocity as the motive fluid passes through the motive nozzle.

Given that the pumps we use are not particularly suited to high pressure apps and are very susceptible to flow rate loss due to increase head/decreased pipe diameter. I'm wonder what the effective flow rate increase we would experience might actually be.

As a simple example, if the flow of the motive fluid through the nozzle results in 4/5ths decrease in flow rate. Then the effective flow increase due to the educator would be zero.

Note that this is a play example. I have no idea of actual numbers or whether this is actually a concern. I'm asking in the hope someone knows.

In fact I only read one or two wiki articles.... Is the nozzle at the motive inlet even required?

The 4 to 1 ratio comes from the product literature. My experience is that product literature can be embellished slightly... However, there is a lot of real world use for eductors, so I personally am not dismissing them as of yet.

So my understanding is (in lamens terms) that the water flowing through the tapered nozzle is sped up via the venturi design which assists it in pulling the tank water through it? So its pushing and pulling at the same time sort of thing.

Might be worth splitting this thread up and title the back half as eductor, what do you think?

Just add "Eductor" to the title .

Removing post , splitting threads gives me the sh....

+1

The title is now a little confusing, the extra bit was on eductors.

Thats why I thought it would be better to split it but I didnt want to sh.. people off

What do you guys want it to read? It doesnt bother me because I am the search master and Id find it if it was called 'lqiwurgfwergqefvq52345r&^$#%&^'

Myth or fact? And a bit about eductors.

Like others, I have only just heard of these eductors but it does seem that with a tiny bit of tank design (ensuring that the solids are in the same place either by wter swirl or bottom deformation) then this could be a brill way of enhancing the SLO. Or am I reading this all wrong? And as a corollory, what sort of pump is required for the primary flow? Is it the normal pump one would use?

After a bit of googling and reading I now remember Ive come across these before in different applications in the mining and maintenance industry. Its the same nozzle that is on a CO fire extinguisher too. Be interesting to see if used on a pump what improvement it would make to swirling a large body of water.

-Cut and paste-

Water jet eductors utilize the kinetic energy of one liquid to cause the flow of another. Eductors consist of a converging nozzle, a body and a diffuser and resemble syphons in appearance. In operation, the pressure energy of the motive liquid is converted to velocity energy by the converging nozzle. The high velocity liquid flow then entrains the suction liquid. Complete mixing of the motive and suction is performed in the body and diffuser section. The mixture of liquids is then converted back to an intermediate pressure after passing through the diffuser.

'lqiwurgfwergqefvq52345r&^$#%&^' is better than what you have changed it to, Charlie.
If you are going to change the title of a thread with my name to it then please use correct spelling and punctuation. It is an Eductor, not a Reductor, and there is no ownership nor abbreviation involved so no apostrophe required when pluralised with the addition of an s.
A suitable title might be 'Myth or Fact: DO Depletion by Pumps and Use of Eductors'.

Cheers.

waaa... waaa


happy now