Blower design

[Vicoor]

I can imagine that this design would move a good volume of air, but I would be concerned that without some really tight clearances in the housing that you may have difficulty getting much head pressure out of it.

It's definitely an interesting project, I'm looking forward to seeing the results.

[Tony]

Vicoor,
What you say might be true with a single sided open blade rotor design. But with a fully shrouded rotor, the only air leakage path will be right at the rotor inlet.

It is possible to slide the rotor along the shaft and position it so the clearance between the rotor inlet eye, and outer casing can be closed up to almost nothing with a very simple adjustment.

In practice, a very few CFM of air leakage is nothing compared to the massive air volume possible with a large blower like this.

[Thomas Vaught]

The Ametek 115923 Vacuum motors (SUper Flow type) have a fairly
large gap between the front drum opening wall and the physical diameter
of the drum. The drum is approximately 5.7" in diameter, The fan diameter is about 5" (from memory, I took one apart one time), and
the gap from the front of the drum to the fan front plate was about 1/8".

Scaling these up on a 3 to 1 relationship:

Drum would be 17.1", Diameter of fan would be 15", and the front gap
could be as great as 3/8" (all things being equal). I would think with some effort you could get a consistant 1/4" clearance, (or less) on the front of the drum and have excellent performance.

JMO

Tom V.

[bruce]

Figured I'd post up a pic so everyone doesn't think I let this project sit . . . picked up the material for the blades this past week and I machined one up to see how it fits, here is a pic of temp attached to the blower side. the blades are attached using 4 alum 1/8" pop-rivets. Had some concern the rivets would be to long due to the thickness of the channel material but I was able to work around that minor frustration.

Some "Redneck Engineering" at it's finest!

I should get the blower wheel finished this week, I'll post more pics of my progress.

[bruce]

Blade backside

[bruce]

Ok a few more new pics for you this one shows the blades mounted to one side of the wheel

[bruce]

end view of the blower wheel

[bruce]

Completed blower wheel, still need to cut the hole for the hub and air inlet.

I wanted to get it together to see if it would all work out before adding any more valuable time to the project.

[bruce]

Its one BIG OLE vacuum cleaner blower I'll say that! My wife asked me what I was working on . . . I'm thinking she is thinking "humm that would make a nice central-vac for the house"

[Tony]

Looking really good there Bruce.

[bruce]

Progressing slowly though, to much procrastination on my part

[bruce]

I picked up the steel for the blower housing this morning so I have a new pic to add.

I laid the blower wheel on a side plate (25"x26") to show everyone how I plan on making the housing. The coupling nuts will form the arc for the scroll and hold the sides together. They will be through bolted to the side plates, a strip of metal will be welded to the nuts (ut not the side plates) to form the scroll.

If access is needed to the blower wheel the front side plate can be easily unbolted to gain access. So now all I need to do is locate and drill all those holes . . . one thing else to add . . . this is going to be one big ole vacuum cleaner!



Edited By bruce on 1184976455

[Tony]

A picture is worth a thousand words !

[bruce]

Is it clear now how I'm doing the sides?

I had a chance today to locate and drill the holes in one plate, I then match drilled the second plate and I'll enlarge the holes to final diameter on the drill press. I had to round the corners on the plate so it would clear my milling machine base. I'll add another pic tomorrow.

I had a fellow in my shop this morning who is a non-flowbench guy and he was amazed at the blower wheel when he saw it sitting there. Had to ask all about it

[Tony]

All much clearer now Bruce after seeing the pictures, I understand now why you are planning to have a rectangular outlet port.