Axial pump 3

[zenjest4u]

Hi Folks,
This is my first post:

I have a concept for a pump that I need to flesh out a bit and Im looking for some resource to help me come up with a design.

Im looking to raise a high density fluid with an axial pump design about 6 feet vertically.
For the application the solution weve gone for is a series of impellers/propellers/fans encased in a 6 foot tube that we would drive from the top (sort of like an archimedes screw).
Im looking to achieve a flow rate in the region of 50-100 litre/minute.

Are there any formulae about that can help me determine how to choose parameters such as

1) Pitch
2) Number of stages/fans
3) Pipe diameter/ Fan size
4) Operating RPM
5) Power requirements


Also are there any considerations when we use impellers in series?
Also does the bottom impeller need to be thicker becuase of the depth submerged in fluid?

Thanks in advance, Im looking forward hearing back from you!

C'mon internet Gods!...make this happen!!
Best regards
z

 

[Strong]

I have worked on one of these screw pumps to investigate a drive shaft failure:

https://www.bing.com/search?q=waste...6dNq2OsTDeJ!NVeOaL0QaKxnNU5vQDpjzzaLY&plvar=0

Contact the vendors for lift and flow specifications.

Walt

 

[zenjest4u]

Thanks for your reply Walt.
I only used the Archimedes screw as an example. What I’m really looking at is something like multiple axial impellers in a tube.
This is because, to complicate things more a lot of the parts need to be made from ceramics due to the corrosive nature of the material we’re looking to emulsify and transport.
The single screws are good for transport but won’t emulsify and twin screws are out because of the wear on the ceramics.

I’m basically just looking for guidance with regards to roughly choosing dimensions while drawing up CAD for the machinist.

Internet Gods!...keep em coming!!

 

[LittleInch]

Have you heard of google?

It is very useful for questions like this and when you enter the words "Axial flow pump design", very useful websites like this turn up

http://www.ijsrp.org/research-paper-0918/ijsrp-p8104.pdf

https://pdfs.semanticscholar.org/ad66/657145675c16297053219ca4d83fc613076e.pdf

There even Youtube videos and links to vendors (Yes really!)

Or you could just find a good vendor and look at their website.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[zenjest4u]

Thanks for that.
I'll try to wrap my head around these equations and get back to this forum.

I have an additional question in the mean time. Apologies if it sounds basic but I just need to carify my thinking here.

My fluid density is very high and Ive also got design constraints on the diameter of the shaft. I was also hoping to keep costs down by getting off the shelf impellers. These would limit the achievable head.
I can measure the values of the blades and plug them back into the document maybe?
Also, Would it then mean impeller stages should be within the achievable head so that once the fluid is transported up the first impeller set it gets picked up by the next set of rotors?

Thanks for your support guys

 

[zenjest4u]

**design constraints on the diameter of the pipe

 

[Artisi]

What is high density, put a figure on it.



It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[zenjest4u]

Somewhere between 2.7 and 2.8 g/cm3. We're pumping molten aluminum.

I cant go with the typically highly accentuated thin blade design because Ive got to build parts with ceramics. So the blades and fams need to be quite blocky. Furthermore due to the moments and use of ceramics the chosen blade concept design would need a circumfrential support ring and the diameter is limited to an extent. So theres not a lot of aerofoily stuff going on.

Because cost is another constraint, I was hoping to get a lot of my parts off Alibaba but I need to undestand how much lifting I'd be able to get per fan so that I can use the minimal number of fans. The alternative is to go overkill and have fans every few centimetres.

Hope this clarifies things more

 

[Artisi]

why are you trying to reinvent the wheel? - seems there are already pumps available for similar applications.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[zenjest4u]

Yup- theyre generally all cenrifugal pumps for transport/circulation. Unfortunately theyre not suitable and pretty expensive pieces of kit.

I'm looking to create a device for specific melt processing route ive come up with that will transport material at the same time....its something Ive adapted from my doctoral studies in my free time so yes, I am reinventing the wheel (although its not a wheel)At this point in time its still very much POC stuff. There's a small local foundry thats letting me have a play around as and when I need to

I just need to understand how to calculate how much each impeller fan would raise the fluid wrt RPM and wall clearance and how to calculate that gap to leave inbetween impellers in series.

 

[Artisi]

Lots of luck.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[electricpete]

if you haven't done it yet, you might seek help from a application engineer for a large pump company like sulzer.

if you are insisting to design it yourself, you may be able to build a smaller prototype for testing purposes and scale the results through dimensional analysis based on diameter, fluid properties and speed. That type of scaling applies to many pumps and fluids, but I'm not sure if all of the relevant properties of this particular fluid are captured in the scalable properties of viscosity and density.

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(2B)+(2B)' ?