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Students invent quieter leaf blower

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Re: Students invent quieter leaf blower

#61

After reading all comments, not rushing to the comments, I have to say, I have a quiet leaf blower to, it is, as mentioned in this thread somewhere else, a rake and I would appreciate if more people would use one.

Why rake at all? Mulch them instead. Raking them into a bag to have removed from your property to add to a landfill just seems like a very strange decision to me.

Depends on the state of the property. On a low water and au naturel yard, sure. Manicured lawns and sterility are all about anthropocentrism while expending concealed absurd treasure and effort without much concern for the soil losing nutrients. Or it's the middle class still clinging onto disappearing symbols American dream of how "rich" they are like the French aristocracy once did. You should've seen how deep green with a tint of blue my dad's 30' x 40' front lawn of Bolero dwarf fescue was, which required mowing twice a week in the summer by you know who, tens of thousands of gallons of water, and regular fertilizing.

Re: Students invent quieter leaf blower

#62
post #22

After reading all comments, not rushing to the comments, I have to say, I have a quiet leaf blower to, it is, as mentioned in this thread somewhere else, a rake and I would appreciate if more people would use one.

>a rake and I would appreciate if more people would use one. Most of the leaf blower noise in neighborhoods is cleaning up tiny grass clippings off of driveways and sidewalks instead of handling the Fall season's dead leaves, like this: https://www.youtube.com/watch?v=ak5VoB-ceeU&t=0m06s Rakes don't help with grass cuttings. People could use brooms to sweep up the grass but homeowners and lawn crews don't do it that…

Most of the leaf blower noise in my neighborhood is the one or two guys on the crew who's job it is to run the leaf blower while the other guys are doing the lawn mowing or edging.

If it was that guy's job to use a rake and broom instead of a leaf blower, the same amount of cleaning would be done.

Re: Students invent quieter leaf blower

#64

After reading all comments, not rushing to the comments, I have to say, I have a quiet leaf blower to, it is, as mentioned in this thread somewhere else, a rake and I would appreciate if more people would use one.

Why rake at all? Mulch them instead. Raking them into a bag to have removed from your property to add to a landfill just seems like a very strange decision to me.

I mulch, but it's slower and requires more frequent mowing. The first mowing of the year (I always wait too long) is nearly impossible with a push mower mulching.

Re: Students invent quieter leaf blower

#65
post #32

Earlier quoted context omitted.

The problem with electric leaf blowers is that they're no good for people who need to blow leaves all day; and most of the leaf blowing is (in my experience) contracted out rather than done by home owners. I have an electric blower that I use for getting leaves off my decks (you can't rake a deck and it's actually a remarkable pain in the ass to brush leaves off a deck) but if I got a contractor in to do my garden (w…

Dewalt has battery packs that are quickly interchangeable and pods with rows of batteries that can be recharged inside a car or truck while on the go. I'm hoping this becomes adopted more and more as the tech is already here.

Proprietary batteries with a format that changes subtly from model to model are not the answer.

Re: Students invent quieter leaf blower

#66

Earlier quoted context omitted.

I can't help but notice in that video that it's really not moving the leaves too much, and that's on the most ideal surface you could have.

That's a good observation. Making a quieter leaf blower by greatly reducing its output is pretty easy. But the professional landscaping crews getting paid by the hour won't choose a tool that makes their job take 5x as long.

Random thought: Would it be beneficial if residentially-annoying equipment was required to fall into certain standard frequency/harmonic pprofiles? Would that make it easier and cheaper to design absorptive or anti-noise measures?

In other words, a world where you could buy super-cheap earbuds guaranteed to nullify all leaf blowers.

Re: Students invent quieter leaf blower

#67
post #8

Minor nitpick about the reporting: > The team reduced the overall leaf blower noise by about two decibels, making the machine sound 37% quieter. While a 2 dB reduction in noise does represent a 37% reduction in acoustic power, our perception of sound is logarithmic so this is extremely unlikely to "sound 37% quieter"-- Assuming the reduction is from 50 dB to 48 dB, it will sound about 4% quieter. Much more significan…

In the video, we see the students briefly rotating the model in the CAD software—with translucency on—it looks like the one main stream is divided into many spiral chambers which then exit distributed along the rim of the attachment's opposite side. With that in mind, I wonder how much, if at all, the reduction would be if the entire nozzle were designed this way, instead of just the end bit.

They probably should look at this for server cooling as well. At 2u or smaller those things are leaf blower loud, and there’s a lot of depth in those cases that could be sacrificed for decibels.

Re: Students invent quieter leaf blower

#68
post #23

A few years back Moxie (of Signal) put up a video[0] of a quiet leaf blower which was pretty sweet. His design appears to be quieter than this one. Either way this is great, as a person highly sensitive of sound I support all technologies that reduce excessive noise. [0]: https://x.com/moxie/status/1582154037700399104

I can't help but notice in that video that it's really not moving the leaves too much, and that's on the most ideal surface you could have.

Hmm. They claimed they didn’t reduce the thrust. Maybe the vortex is screwing the blowing-ness or they are measuring it wrong.

Re: Students invent quieter leaf blower

#69
post #66

Earlier quoted context omitted.

That's a good observation. Making a quieter leaf blower by greatly reducing its output is pretty easy. But the professional landscaping crews getting paid by the hour won't choose a tool that makes their job take 5x as long.

Random thought: Would it be beneficial if residentially-annoying equipment was required to fall into certain standard frequency/harmonic pprofiles? Would that make it easier and cheaper to design absorptive or anti-noise measures? In other words, a world where you could buy super-cheap earbuds guaranteed to nullify all leaf blowers.

Figure out what ranges of sound are attenuated well by foliage, siding, wall insulation, gypsum board. Though it’s probably windows most of the sound comes through so what frequencies are lowered by double pane windows.

Re: Students invent quieter leaf blower

#70
post #48

It's mentioned in the article but easy to miss, this is an improvement on the already much much quieter electric leaf blowers that are readily available. The ones you are thinking of are two stroke gas powered ones which are loud as fuck and terrible for the environment, anyone using one of those could have gotten a quieter electric one but chose not to, which means they definitely aren't going to use this improved e…

> they definitely aren't going to use this improved electric one.

The (major) manufacturer they demonstrated it to seems to have adopted it.

Maybe they'll expand the concept out over time to the two stroke ones as well. :)

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