Blower housing with bellmouth inspired by Retired2's build

[Bill.F]

Greetings all.  I wanted to share images of blower construction for my eventual DC system.  I was truly inspired by Retired2's separator build, so I've tried to incorporated several lessons from his experience into a blower build.. Namely:

   
• 2-layer polycarbonate sidewalls (instead of plexiglass)
• generous bellmouth transition from inlet
• outsourced the MDF machining to a 3rd party!  :-)

I just got the housing together this morning.  I still have a lot more to go obviously, so it will be quite a while until to I get to try it out, but I'm happy with what I've got together so far.


Retired2, thanks once again for posting details on your build!

-Bill.F

[retired2]

Bill.F

I see two very significant differences between your build and mine, and I fear these differences may result in a large amount of by-pass in your build. 

The first difference is your bell mouth outlet is flush with the top inside of the separation chamber.  Most all builds including mine adhere to Phil's recommendation that the outlet protrude into the separation chamber by approximately 1/2 the diameter of the outlet pipe. 

The second difference, and maybe not as critical, is your inlet appears to transition from round to square.  I advocate round to rectangular (taller than wide) in order to put the incoming waste stream near the outside wall and over the drop slot.  In your photo 006, you can see the square inlet stream puts at least some of the incoming air close to the bell mouth flange.  Now maybe this isn't a serious problem because many successful builds have used round inlets which also allow some of the waste stream to pass close to the outlet pipe.

At this point, I recommend that you only do what is necessary to test your build.  If the performance is satisfactory, then you can put the finishing touches on it, but if you get a lot of by-pass, I regret to say it is going to take some re-work to correct it.

Good luck.


Update:  I just spotted another potentially serious problem.  I don't know exactly how you plan to finish the bottom of your separation chamber, but it looks like you have a serious "ledge" around the inside of the chamber wall.  Ideally the drop slot should be flush with the inside of the chamber wall.

[Bill.F]

Sorry, I should have been a bit clearer.  An impeller is going in there; it's for the blower.  (I just haven't attached the impeller or motor yet).   I was looking at the blower plans on the Pentz site, where he's got maybe a 1/2" roundover.  Just seeing the bellmouth used on the tophat opened my eyes to how one could maybe be used on the blower inlet, as well.  So I thought I'd give it a go.

[Rudy81]

Very interesting design for a blower housing. How thick are the poly-carbonate sheets?  Did you adhere them at all to each other?

[Bill.F]

They're each 1/8".  Two sheets for a sidewalk thickness of 1/4".  At first I was thinking one sheet, but all the good posts here got me thinking about bendability.  They're not attached to each other, they're just tucked into the same slot nice and tight.

[Rudy81]

Bill,
Thank you.  I am about to start a build for a Thien separator and having clear sides would be nice.  I need to research this a little more, but you did a very nice job with the blower housing.

[alan m]

very nice.


id love to see a video of that runnin with the seperater adn without.
im sure there would be some info to be gathered ffrom that

[retired2]

Sorry, I should have been a bit clearer.  An impeller is going in there; it's for the blower.  (I just haven't attached the impeller or motor yet).   I was looking at the blower plans on the Pentz site, where he's got maybe a 1/2" roundover.  Just seeing the bellmouth used on the tophat opened my eyes to how one could maybe be used on the blower inlet, as well.  So I thought I'd give it a go.

I guess I should have paid more attention to the title of your post, but you really threw me when you said you were inspired by my build.  I immediately concluded you were building a separator, not a blower.  One thing is certain, no one can say they are inspired by the blower I built !