stall mats

I just did a search for "Regenerative Blower"...all I can find is 3 phase multi thousand dollar items, or .5HP blowers that wouldn't be suitable for running from the eu2000i.  I think there's gotta to be a middle ground :)

What do you guys think of this:
EBM Motorized Backward Curve Impeller, 115V, 530 CFM, 100watts
Is this the kind of thing you were thinking, Jedi?

I've referenced you to ebay multiple times.  

You aren't going to find any deals buying new.  

As I sort have sort of  pointed out.  


I think it would serve you well to go back to the inline blowers and go to the ebay link.

I have one of them sitting right here and I can plug it in and give you some idea of what you might want to know.

Just plugged it in, modestly impressive, but I selected this one last summer to run on 110 vac solar to move warm ceiling air into a highly insulated room via a 4" corrugated [drainage pipe] duct.

It's only rated at 80 watts, pretty whimpy compared to what you need, maybe 300 watts or so.

Similar to this one. [Ignore shipping, should cost abt $18.

My blower, sorta...

Haven't gotten around to installing it yet.  

Is there a simple test you'd like me to try?


There are some nicely priced regenerative blowers on ebay.

No need to get testy :)  I did look on ebay, and a ton of other places; the prices i've mentioned are ebay prices, new prices are in the multi thousands of dollars for anything marked as 'regenerative blower'.

I searched for "Regenerative Blower", and I've clicked through a couple hundred of the results looking at the specs.
The cheapest i found was over 200$ - on ebay - and they are all monstrous beasts; most of them require 220v or 3 phase power and weigh a ton, and most are too physically large to fit in the enclosure and alot of them have 15-20 amp startup surges and >300w running requirements.

If instead I look at "inline blowers" or "backward curved impeller" blowers, then there appear to be options reasonably priced (even new) that appear to generate quite a lot more pressure than the tubeaxial fan I have now.

The link you posted to 'like your blower' isn't a regenerative blower as far as I can see? Or is the term used also to refer to the inline fan you linked?  Maybe I am looking at different things than you are in my search results.  I looked at inline blowers on ebay but the ones that I found only list RPM's and CFM, no datasheets for their static pressure vs. cfm curve are available on any of the ones I opened, so it's really hard to gauge if a particular fan is going to work at higher pressures.

The in-line blowers seem to be centered around being put in-line into duct-work that matches the intake/output dimensions which looks to be a bit different than what i'm looking to do; reading this document, it looks like I could install the fan that I linked above right into the baffle area between the inner and outer box walls, pulling air from the main compartment.  Is there any benefit to getting an in-line blower like you linked to over the backward curved impeller blower that Jedi was recommending?  I noticed that the blowers under 'Regenerative Blowers' can produce a TON of pressure.  From your recommendation, it sounds like you have an idea of what kind of pressure i'll be seeing; How much pressure do you estimate i'd need to overcome the baffle setup?   How many CFM of circulation do you think i'll need?  I was estimating 150cfm per generator would do it from what I've read; what do you think?

Here's the datasheet w/ pressure->cfm curve for the R2E225 I was looking at
And here's it's bigger brother...225, 1400cfm max...what do you think?

Here's one...

Blower

This is the same one I bought many yrs ago that I mentioned above, I think.

Or this one? $99....

Another


I like this one...

Shippings a little high from Canada but price is right



Some might need a small transformer, or if 3 ph, an extra cap or two and a voltage relay to start...



But, I agree, I'd skip the fancy regen blowers and go with one or two inline blowers.  They use too much juice and your gennys would be working hard just to power them.



I can't give an opinion on what would ackshully work in your application, other than I'd go with one or two 300 watt 6 inch inline blowers off ebay and thermostatically control them.

The little 4" inline I bought last year to move warm air into a well insulated room, that uses 80 watts, seemed pretty whimpy when I ran it last night, and from what I perceive of your project, I think 80 watts is far too little to move sufficient air.


What about mounting one or two inside the box and feed their intake with 10 or 15 feet of corrugated drainage flexible pipe to attenuate sound thru them to the outside of the box?

Or divide the cooling ductwork in two powered by separate blowers ---also for redundancy?

Interesting design. You're rightly worried about air flow. Those baffles won't help any.

I've been living off grid the last few months, mostly reliant on a Honda EB3500. I kept it under the front of a 5th wheel for most of that time, never had an issue with it.

Earlier this month I put it in a small cargo trailer. Installed a small vent a few inches from the generator's exhaust. Another small vent on the other side of the trailer. When I tried running it with the door closed it began surging after a while. Not getting enough air. Keeping the door half open fixed this problem. Until yesterday.

Yesterday I ran it with the door wide open and after an hour or so it began surging again. Had to stop it and let the trailer air out a bit before starting it again, after which it ran fine. The air was noticeably foul from exhaust.

I plan on enlarging the existing vents and installing at least two or three more vents, a fan, and probably an exhaust extension. Noise isn't an issue for me, I just want to be able to run the gennie in the cargo trailer where it's protected against rain and is more secure.

Hmm, interesting.  I've run the eu-2000i @ non-econo for 3 hours in the box with only the current tubeaxial for airflow and the generator didn't surge... without the fan it surges within ~30 seconds.  With one of these blowers, I think I might see more than triple the airflow based on the performance curves compared to that of my current fan.  I read about a few other people attempting similar things for RV setups and they all failed due to heat.  It's the biggest issue for sure.

In other news, my hose<->NPTF fittings arrived from zorotools today!
So I plumbed the box! :)  It's got a nipple QD on the outside that the BERGS fuel tank connects to with the same DM series parker quick disconnects that came with the tank.  Inside, I used a T junction-> Hose<->NPTF Male<->Hose to split off the fuel line for the first generator, and attached a DM series receptacle QD to that NPTF male thread, and then attached a 90 degree elbow hose->to NPTF male thread on the end of the hose, that I attached another of the DM series QD receptacles to.  I then made up 2 short hoses with hose->NPTF male->DM series QD nipple on one and and hose->NPTF male->DM series QD receptacle on the other side.  The nipple connects to the QD receptacles plumbed into the box, and the receptacle end snaps right onto 'the upper red cap' from BERGS that came with a DM series QD nipple already.  Yay.

Note that you can see the thick rubber foam that I used on the bottom of the box. When the box is laid down on concrete this foam stuff produces a 100% seal entirely around the bottom of the box.  It looks a little wobbly because I can't apply things in a straight line (apparently) but it's reasonably sturdy.  It's cheap, anyway.  As long as the box doesn't get moved around I think it'll do.

I'd REALLY like to use Trim-Seal from Trim-Lok, but the stuff I want needs a 3/4 inch edge thickness for part of the box, and 1/2 inch edge thickness for others.  And it comes in 100 foot rolls. That cost 225$ each. :(  Anyone need some trim-seal? :D Group buy? :) lol
this would be the stuff:

The rubber tube would be in position C, and the U shaped metal reinforced part would (a) seal the bottom of the box well and (b) allow me to tack through the sides of the U shaped area and really secure it down without using any glues that will fail.  Does anyone know where I can order something like that by the foot? The minimum order is a killer.

I then used some 'mounting zip ties' I found at lowes to affix the hose to the side of the enclosure; these zip ties have little holes that you can use to mount the zip tie with a standard wood screw.  It's quite solid :)


Power wiring this weekend, and I'm going to order a blower.  I'm planning on leaving the 550cfm 80w tubeaxial where it is on the exhaust side, and putting the blower on the intake side inside the interior box.

Yeh, I did see all of those while looking through but discounted a couple of them as not being practical for a single eu2000i to power (and requiring 220v, I wasn't aware I would even be able to power them on an eu-2000i at all...), and the fuji you linked says a max of only 18CFM of airflow, and 50hz power on it; maybe I am being too literal in reading the specs and these can be made to work but I don't think I know enough to make it happen even if they weren't too big to fit in the box; which i really want to do to avoid produced 65-75db of noise outside the box just for intake fans.

I'm actually surprised that the current tubeaxial fan is doing as well as it is, given your feedback on the 6 inch blowers.  Fans do get way more efficient with larger blades, I guess...thanks for the heads up, I appreciate the insight

Why not just seal up the baffles on the bottom with another piece of MDF?

You could line the bottom of this sheet with sheet foam rubber (i.e., a sleeping blanket ground pad or exercise mat).

That way, you won't have to set it on a perfectly flat surface to provide a good seal - The large surface area of the sheet foam rubber will seal around any irregularities in the surface it's resting on.

Adding a bottom over the baffles would also increase the enclosure's rigidity, reducing its tendency to work as a sounding board for generator noise.

Not to mention it would prevent your box from hovering when you put a high enough pressure blower on it.  

I didn't give feed back on a 6" blower, I have a 4", as I mentioned several times IIRC.  

Here's an issue I see with your design that might need to be addressed, if I understand it correctly.

You have mechanically linked the structure of the 'box' walls from the innermost area to the outermost, from what I have briefly looked at.

Pls correct me if I'm wrong.

The dynamic connection of the inner to outer walls with carry a lot of both high and low frequency energy to the outside, it would seem...

Maybe separate the suppression system into two mechanically isolated housings.

When I build a room inside a building and I've done more than 2,  I make NO connection to the outside building wall and the inner room freestands on it's own. It's amazing how quiet they are inside...


A cheap and likely effective gasket between the box where it contacts the floor, might be plain old foam pipe insulation.

It could serve to mechanically isolate the box from the floor and attenuate sound energy that would tend to escape underneath.

And another issue follows in the post post...    

In housings for RF [particularly microwave] circuits, it's common to include an absorber for energy for frequencies of interest, to suppress all sorts of spurious effects.

Small ferrite loaded plastic 'pieces' are commonly used, ----and in my interest to max profits, I found that black conductive foam [with the right resistance property] --works great.  

It might be useful to add more material, ---like maybe, plastic insulation foam, at various places inside to absorb internal sound energy.

Then, some of the sound energy will be absorbed and you won't have to worry about designing a baffling structure, to prevent escaping.  


This as well as isolating the inside and outside of the noise suppressor, might greatly reduce the airflow mechanism requirements!

You are totally correct of course :)  Making this a single box rather than two was a trade-off, but it was an intentional one. I actually planned originally to have two boxes; one inside the other, with exhaust/intakes on the outer box on the front/back, and exhaust/intakes on the inside box on the sides  It would've definetely been quieter since the inner and outer boxes share the same roof piece as it is now.

But there were a bunch of problems with that idea that made me decide to make one for noew:
1. 2 boxes that size made from MDF would have taken 4+ sheets to build; the lid for the bigger box would've been most of a sheet all by itself and the inside box would still need it's own lid.  Storing the 2 boxes would need a ton of space and this needs to fit in my car port with my water barrels & fuel and my car still needs to fit in there sometimes so I can work on it on the slab :)

2. Wiring and fuel lines... right now, I can run the wire through the 'dead space' area between the two boxes and leave it permanently installed.  If I had to be able to separate the outer walls from the inner, i'd have to make some sneaky methods of keeping the wires/tubes from being tugged/damaged and disconnectable, which would need access to the interior without having to move the boxes to disconnect things that would be damaged by separating the boxes

3. I'd probably lose my baffle setup with that design, or the inside box would need to be as big as the entire box is now, meaning the outside box would be even bigger than the enclosure is now. I was considering making the outside box the same size as the entire enclosure is now, and attaching the baffles to the inside wall of the outside box, then lining the inside edges of the baffles with rubber foam tape that would seal to the internal box's outside walls as the top box was placed around the bottom box, with the foam providing a mechanical damper between the two boxes, but I didn't thiink it'd be durable and getting the boxes fitted would be a PITA.  And I figured that if I wanted to, I could always make another huge box and put it on top of what I've already got when I move somewhere I can permanently install it at.  The inner and outer boxes being connected to eachother was one reason why I insisted on using MDF for assembly, since it is so dense and doesn't resonate much compared to, say, birch plywood sheets.


The foam pipe insulation would work i expect; do you think it'd work any better than the 3/8-in thick rubber foam I have on there now?

Actually, I've got butyl rubber mat designed for sound deadening that i'll be putting on the inside of the hatch once it's been cut out, and on the inside walls of the interior box.  I've also got a combination of open/closed cell foam approx 1/4in-thick that I am planning on putting on the surfaces inside the baffle areas.

Sorry, typo :)
I'm thinking something like this since i've already got a 10" hole cut but i've been finding that most ebay sellers (incuding this one) don't indicate manufacturer, model # or spec sheets w/ pressure vs. cfm curves so it's hard to decide.

The 10" here looks good.;780 CFM and only 52db is impressive.
This seems ridiculously efficient @ 150w. But no pressure curves provided.  It claims 790 cfm and says 2.15" static pressure, but I somehow doubt it does 790cfm into 2.15" static pressure @ 150w. Nobody else comes close.  Seems like a minefield.
This at least shows CFM #'s at various pressures... 700cfm @ 1.0 in.wg looks to be damn good.
Wish I could find these locally so I could test one out and bring it back if it turns out not to be enough. Hm.

Color me frustrated

To hold your top on- Pop up camper latch

Small bar goes on top, latch on bottom.

Absolutely perfect :D thanks man :D