if you can imagine a solid or hollow piece of tube say 50mm in diameter and say 600mm long with a 10mm hollow plastic pipe fixed at the bottom end of the large tube at 45 degrees to the length and then wound at equal distance all the way up as a spiral (there are similar ones shown on youtube) tilt the large tube at 45 degrees and turn in a direction so as the bottom of the small tube scoops up water from a basin and eventually brings the water up the tube to the top and it pours out. my thought is this .if the large tube is 50mm in diameter and one small pipe is 10mm in diameter then if four more 10mm tubes were added side by side copying the same spiral fashion then I assume five times more water would be picked up and ejected at the top with the same revolutions ?

Sounds like you are describing a multi-pitch or multi-start screw where there are two or more threads running together on a single axis similar to what a DNA double Helix looks like.

 

Yes i also wondered if thr axle was cone shaped and the wrapped tubes reduced in size following the shape of the cone would the outlet pressure increase ?

 

Yes i also wondered if thr axle was cone shaped and the wrapped tubes reduced in size following the shape of the cone would the outlet pressure increase ?

An Archimedes screw is a water lifting device not a pump capable of producing pressure. They even in the time they were invented were only used to raise water from one level to another, like a river or lake to a field for irrigation.

 

An Archimedes screw is a water lifting device not a pump capable of producing pressure.

I saw a car wash water pump that was a screw shape in a rubber housing, and it made lots of pressure at a low volume.
Your typical Archimedes screw has pretty bad sealing around the perimeter, but this one application looks similar and produces good pressure.

 

I saw a car wash water pump that was a screw shape in a rubber housing, and it made lots of pressure at a low volume.
Your typical Archimedes screw has pretty bad sealing around the perimeter, but this one application looks similar and produces good pressure.

hi thanks do you know anywhere I could see a picture of this

 

An Archimedes screw is a water lifting device not a pump capable of producing pressure. They even in the time they were invented were only used to raise water from one level to another, like a river or lake to a field for irrigation.

my idea was to modify this into a conical shape to use as a pressure pump?

 

my idea was to modify this into a conical shape to use as a pressure pump?

Hi,

Well if i remember right, incompressible fluids show zero divergence which means that if 1 gallon of water enters the inlet every 1 second then 1 gallon of water leaves the outlet every 1 second. Actually that's probably conservation of mass. The way to create pressure is to reduce the diameter of the outlet, that way the 1 gallon across 1 square meter at a rate of 1 gallon per second has to leave the outlet at 1 gallon per second as before, but now it might have to pass through an opening only 1/2 square meter so the velocity of each particle of water must increase to maintain 231 cubic inches of water leaving every second.

If by 'conical' you mean making each pipe conical, then you will create more pressure at the outlet. If you mean make the screw itself conical but with cylindrical tubes, then it's only dependent on the speed of the rotation.

 

hi thanks do you know anywhere I could see a picture of this

No. I saw it in person. You can go to Warsaw Indiana and look in the equipment room of Frauheiger's Car Wash if your Wayback machine can get to 1972.

 

Hi,

Well if i remember right, incompressible fluids show zero divergence which means that if 1 gallon of water enters the inlet every 1 second then 1 gallon of water leaves the outlet every 1 second. Actually that's probably conservation of mass. The way to create pressure is to reduce the diameter of the outlet, that way the 1 gallon across 1 square meter at a rate of 1 gallon per second has to leave the outlet at 1 gallon per second as before, but now it might have to pass through an opening only 1/2 square meter so the velocity of each particle of water must increase to maintain 231 cubic inches of water leaving every second.

If by 'conical' you mean making each pipe conical, then you will create more pressure at the outlet. If you mean make the screw itself conical but with cylindrical tubes, then it's only dependent on the speed of the rotation.

as you pointed out make each pipe conical onto a corresponding conical shaft would this work do you think ? thanks

 

I saw a car wash water pump that was a screw shape in a rubber housing, and it made lots of pressure at a low volume.
Your typical Archimedes screw has pretty bad sealing around the perimeter, but this one application looks similar and produces good pressure.

Think your describing an axial screw pump. Don't think it could be turned by hand fast enough to produce pressure.

 

Think your describing an axial screw pump. Don't think it could be turned by hand fast enough to produce pressure.

what about a small low geared dc motor ?

 

what about a small low geared dc motor ?

Why not just use a pump that is proven to make the needed volume and pressure you need? Maybe if you described what your wanting the pump for, like irrigation, water mains or what ever, volume and pressure some better ideas could be given. There are quite a few different types of old technology water pumps that are more efficient than the one your trying to implement.

 

Why not just use a pump that is proven to make the needed volume and pressure you need? Maybe if you described what your wanting the pump for, like irrigation, water mains or what ever, volume and pressure some better ideas could be given. There are quite a few different types of old technology water pumps that are more efficient than the one your trying to implement.

I must confess the main reason for my questions is the possibility of using a conical archimedes screw as an input compressor for a small jet engine design or is that a crazy idea ?

 

I must confess the main reason for my questions is the possibility of using a conical archimedes screw as an input compressor for a small jet engine design or is that a crazy idea ?

So why not say that in the first post? Do you think if this(your idea) was a good one, that it would be in the history or literature of the jet engine? Even if it failed there would be a record of it.

 

I will say that my original idea 30yrs ago was a thought of using an archimedes screw in some form as a wind generator and i see there is now a version of that but the other ideas came from the same thought

 

After nearly 6 years here, I am beginning to resent people who send me on a wild goose chase because their goal is a secret. Why did I waste my time telling about a car wash pump when you want a jet engine?

What I want you to know is that there are well qualified designers and engineers that spent their lifetime improving jet engines. (I remember when the engineering limit was the melting point of the metals available. It is probably still the limit.) The best minds and billions of dollars have arrived at the engines in use today, and they are not the shape of an Archimedes screw. You are not going to go back 2000 years and "discover" something better than what a thousand man-years of development have accomplished.

Next time, just blurt out the truth and you will get better answers more quickly.

 

@#12, amen. I love helping people on the forum and spend time trying to find information to help and many of my ways of doing things are "outside of the envelope". Have done this for myself because of the lack of funds and the willingness to try things and make things work. But like you it is frustrating when it takes 3 pages of posts to finally find out that the question asked in the first post is not the real question.

 

@#12, amen. I love helping people on the forum and spend time trying to find information to help and many of my ways of doing things are "outside of the envelope". Have done this for myself because of the lack of funds and the willingness to try things and make things work. But like you it is frustrating when it takes 3 pages of posts to finally find out thatthe question asked in the first post is not the real question.

Thanks for all the replies but I am new to forums I too have always worked problems out for myself and built prototypes when I had time. All the questions I have posted have been genuine and all related to the Archimedes screw. I don't have friends who have the same interest in science and physics as I do, so before I found this forum I had to rely on my own answers but I appreciate what you people give and thanks....kev

 

Most of us are here because we like to figure things out, and help others. But this in your first post, "increase water movement", set the tone here. All forums not just this one need a specific question to get a specific answer. Were not mind readers.

 

@#12, amen. I love helping people on the forum and spend time trying to find information to help and many of my ways of doing things are "outside of the envelope". Have done this for myself because of the lack of funds and the willingness to try things and make things work. But like you it is frustrating when it takes 3 pages of posts to finally find out that the question asked in the first post is not the real question.

And this is exactly why I have a 'sh!t or get off the pot' attitude about question asking on forums.

Rarely am I being rude or snarky just to be that way. It's to get the OP riled up enough to either come forward with what they really want and are doing or to piss them off enough to leave.

As with everyone else here I can not see the lead in of asking a question about Archimedes screws and water and dragging that subject out for 50+ posts and how it remotely relates to designing a jet engine of any kind.

Anyone want to discuss why my cat coughs up hairballs for 50+ posts so that I can get help on figuring out why the master cylinder on my pickup is leaking fluid so that I don't have to do a Google search on brake cylinder designs?