Omni-Jet

I wonder if we should be looking at doing a jet with an odd number of inductors. I know that a 3 blade prop works better than a 4 blade on a boat. And if you think about it how many 4 or 6 blade cooling fans have you ever seen on a vehicle? Or even household fans? They almost always have 5 blades. Maybe that's why a tri-jet works so well?
 

Amazon Forum Fav 👍

Treasure of Victoria Peak - Grab it through Amazon!
It has to do with the area of a circle. if your circle is 10" to figure the area. you multiply half of the diameter (5) by it's self (square) and then by 3.14`````5(5)*3.14
In this case, half of 1/2" (.5) pipe is .25"(.25)3.14=.19625" that is the area of a 1/2 pipe. I have 8 tubes and each tube is .19625...lets round up to .2" so I multiply .2" by 8 tubes and end up with a whole combined area 1.6".

A 2" pipe has a area of 3.14...half of 2 is 1 so 1(1)*3.14=3.14
I have two 2" pipes so I have 2*3.14=6.28" of area
So I'm using 1.6" of 6.28" of a viable area.
 

omnicron said:
It has to do with the area of a circle. if your circle is 10" to figure the area. you multiply half of the diameter (5) by it's self (square) and then by 3.14`````5(5)*3.14 In this case, half of 1/2" (.5) pipe is .25"(.25)3.14=.19625" that is the area of a 1/2 pipe. I have 8 tubes and each tube is .19625...lets round up to .2" so I multiply .2" by 8 tubes and end up with a whole combined area 1.6". A 2" pipe has a area of 3.14...half of 2 is 1 so 1(1)*3.14=3.14 I have two 2" pipes so I have 2*3.14=6.28" of area So I'm using 1.6" of 6.28" of a viable area.
Click to expand...

Yup your right then !!

Go ahead and finish it .
I wanna see the results .
 

panningjack said:
I wonder if we should be looking at doing a jet with an odd number of inductors. I know that a 3 blade prop works better than a 4 blade on a boat. And if you think about it how many 4 or 6 blade cooling fans have you ever seen on a vehicle? Or even household fans? They almost always have 5 blades. Maybe that's why a tri-jet works so well?
Click to expand...

Food for thought...
 

omnicron said:
Food for thought...
Click to expand...

And you are not working with the full 10" in your pressure chamber. 2" deep x5" wide x 10" round on the outside but the inside is 6" round so that gives you 4" inside the chamber. maybe you can check this area out to help you to.
 

Been reading most of the day.

Bernoulli's principle - Wikipedia, the free encyclopedia

Water eductor - Wikipedia, the free encyclopedia

Injector - Wikipedia, the free encyclopedia

Figured out that the eductor should be 25% of your pipe size so a 4" eductor is 1", 3" is 3/4" and a 6" should be 1.5".

P, you where dead on with what you said.

Made a chart for anyone wondering the area of a hole in pipe or tube.

IMG_20140220_0001.jpg

I am close to the target is 1.5" with my 1.57, if I was to take off 1 eductor I would be at 1.37. Which would be better? IDK With the less area for the water to leave, I would get more pressure, but less flow.
If it was a little big I would get more flow and less pressure. If I go from the experience of my 4" jet that I built. My old jet had a 3/4" eductor and the new jet was 1" and there is no comparison between the two. The 1" wins hands down. This was a single log though.

Another thing I'm curious about is the compression chamber. IDK what size it should be or if it matters. The two quad jets I seen, a 6" and 4", were both 4" wide and about 2" tall. I don't know if that size matters or not.
 

Omni, The numbers you are working for jet sizes are a good starting point. A 6" is approximately 2x the area of a 4", so having total orifice size at 2x the area of a 4" orifice is a very good starting point. Don't scrap the project, this is a design that you want to test. I will agree with John that by decreasing the number of jets and increasing their size appropriately can produce very similar results with less work, but this was your desire to try 8 jets, so go for it.
It appears you got past the question of pressure and feed to the chamber- good. I would recommend either 2 2" feeds or 1 3" feed minimum which would keep the velocity of water fed into the jet manifold in the area of 20-30fps feed rate which will limit the losses. While you will always have some loss when entering a larger pipe or manifold area due to turbulence, the benefits of the jet will outweigh these considerably as you mentioned about the infinity jet.
As far as manifold size is concerned, it is important that it is large enough that the flow is not restricted in relation to the feed rate of flow, but if you make it too big you can also increase some other losses from complete dissipation of velocity energy and its associated turbulence as the feed enters the chamber. A fair starting point would be the same diameter of the feed line or a little smaller since the flow will go in several directions as it enters. Finding the perfect size can probably only be found in actual testing a variety of sizes since there are too many variables involved with shape of chamber etc..
You have done your homework Omni- Can't wait to hear the results!!
 

Boat props are not a bit alike as in OPEN non restricted water and thusly propulsion is not the same as jets are confined within the jet. There was a great story published in Popular Mining Mag(Action Mining) called'SIZE WISE" back in 1/87 about a fella who need a 6" waaaaaaaaaay out in the backcountry in a spot even a chopper couldn't fly. We worked like crazy trying to reduce all components to the smallest size to make a BACKPAKABLE 6" over/under run with a hi-dome pump attached to a tiny 8hp briggs IC. He spent the whole summer,thanked me everytime in town, and made a fortune but unbeknownst to me I found the article after he was murdered for his gold. 4" in to produce pressure 3" or so out to REALLY blow that thang up. More supply than demand exactly like a air compressor,hydrolic pumps and municipal water systems. Yes you can conical out the inductors,but must be bigger at the top and then tooooo big to fit into the pressure chamber so you monster out the chamber. ALSO the 11 degree angle of the inductors all meet down the inside the jet and spread out to completely fill the entire chanmber with push force. Take any jet and insert a dowel into the jet,where it hits midstream is the sweet spot,do the same with a dual,now a tri as THAT is what determines how many jets. 1 not enough,2 still not,but 3 does it just right and fills the entire tube with push force. Sure you can go 5-6-7-8 whatever but why ,as then small force by smaller inductors provides 8 miniscule forces instead of 3 much bigger forces. Length of jet after the sweet spot is also important to provide the VOLUME to support the push. Look at any jet after a few 100 hours of use-insert dowel/stick and bingo there is that bump/wear spot from using the side of the jet to PUSH the flow and NOT the center sweetspot which is where you want to be. Take a plate and try and balance with 1 finger -now 2-then 3 WOW instantly magic as equalibrium in form and function is achieved,same as jet. Perfect example is the Dahlke mini tri jet---jet tube flow met in the hose(which was curved) and not near the suction of the longer full jetted model,another shining example of the physics involved. A jet is NOT a simple affair. Still trying to get ol'Prospectors Casche discussion by a half dozen dredge masters and buddy engineers who went into this all in explicit detail. Goota go mining no mo'time to play today-OMG past 8 *&^%$# late already--John
 

I'm certainly no expert on jet building. I'm just saying that maybe since when you have an even number of jets the jets are always directly across from each other, colliding, and fighting each other. With an odd number each jet would be focusing its energy on a different area possibly making it more efficient. Idk. Just something to think about
 

panningjack said:
I'm certainly no expert on jet building. I'm just saying that maybe since when you have an even number of jets the jets are always directly across from each other, colliding, and fighting each other. With an odd number each jet would be focusing its energy on a different area possibly making it more efficient. Idk. Just something to think about
Click to expand...

Jack, This is something I looked into a little. What I found was that it is actually better to have the jets meet at a point and when they do the angle of directed energy deflects and they actually produce a greater sum and evacuate better than each individual jet would by themselves without meeting.
 

Well, being I didn't get a definitive answer, I went ahead and built it as is. I have the tubes all welding in place...I was doing more thinking...
I'm starting to be afraid of thinking lol...
So being I'm going to cut in the water intakes into the sides, the water could end up swirling inside, I've decided to weld on little scoops to help catch the water and direct it into the tubes. May be a waste of time and not needed but it'll only take a few minutes to do and could potentially make it work better.
 

omnicron said:
Well, being I didn't get a definitive answer, I went ahead and built it as is. I have the tubes all welding in place...I was doing more thinking... I'm starting to be afraid of thinking lol... So being I'm going to cut in the water intakes into the sides, the water could end up swirling inside, I've decided to weld on little scoops to help catch the water and direct it into the tubes. May be a waste of time and not needed but it'll only take a few minutes to do and could potentially make it work better.
Click to expand...
Have you watched that video on u tube titles new jet design? It's not exactly the same but close
I'm gona build one simlar to his but instead of tubes I'm gona use angle welded back to the main tube and just angled back in at the end ...
 

G1sammons said:
Have you watched that video on u tube titles new jet design? It's not exactly the same but close I'm gona build one simlar to his but instead of tubes I'm gona use angle welded back to the main tube and just angled back in at the end ...
Click to expand...

Thats what i wanted to explain to omni.. And it Could be made at home. Just a Little more cutting and welding.
 

Watched the video several times. No clue of the internal workings...hard to build what you cant see.
 

omnicron said:
Watched the video several times. No clue of the internal workings...hard to build what you cant see.
Click to expand...
iv talked with him got some basic info it's about the same thing your doing just more holes and smaller holes And there welded to the side of the jet tube instead of tubes ..
I'll check my email but I believe they were 3/8 holes with a tapered square tube welded to the tube .. But he also had built a 5" jet and different pumps and a back blast section for trying to unplug jams .... I have no interest in building the back blast setup ...
But he did have some impressive test results ....
 

Cool, aren't you having Glen build you a infinity? I had to cancel mine for now as funds are running low and I still have stuff to get.
 

omnicron said:
Cool, aren't you having Glen build you a infinity? I had to cancel mine for now as funds are running low and I still have stuff to get.
Click to expand...
yes I'm waiting .. But I figured I'd horse around ...
In talking with this other fella and his test results I think your on to something.. Just make sure your surface area is the same as if you your keene jet would be for the 2 pumps . He explained to me thru testing that the more nozzles he had in testing the more. It acted like a couple or infinity jet.. He had 6 nozzles that were 3/8 in aprox but he had a lot different pumps than you.. It important
That you build your jet to your pump capability .
 

You must log in or register to reply here.

4" dredge upgrades

⬅️ Previous Thread

pls help me guys

Next Thread ➡️

Top Member Reactions

Users who are viewing this thread

Total: 2 (members: 0, guests: 2)

Latest Discussions

Back
Top