Flowbench noise reduction

[rwdford]

I am wondering if anyone has experimented with motor noise reduction

A good idea would be to vent the exhaust air outside with a large ID flexible pipe

Has anyone tried to sound insulate the exhaust side of the motor chamber?

I think this would be worth doing and quite safe since that side of the motor is only ever under pressure rather than vacuum, the material would ideally be non flammable

Just wondering what others may have tired, almost all of the noise seems to be on the exit side

It would be nice to be able to hear inlet ports flowing, smooth flow vs turbulent and not have to wear ear protectors

I could do some before and after testing as I have a decibel meter here somewhere

[Malvin]

Has anyone tried to sound insulate the exhaust side of the motor chamber?

This works very good

http://www.dynamat.com/brands/dynamat-xtreme/

[jfholm]

I am wondering if anyone has experimented with motor noise reduction

A good idea would be to vent the exhaust air outside with a large ID flexible pipe

Has anyone tried to sound insulate the exhaust side of the motor chamber?

I think this would be worth doing and quite safe since that side of the motor is only ever under pressure rather than vacuum, the material would ideally be non flammable

Just wondering what others may have tired, almost all of the noise seems to be on the exit side

It would be nice to be able to hear inlet ports flowing, smooth flow vs turbulent and not have to wear ear protectors

I could do some before and after testing as I have a decibel meter here somewhere

The only trouble with exhausting the air to the outside is the possibility of creating big vacuum in the room you are in. If that area you are in is tight enough and you are flowing at 28" (1 lb psi) you could suck the drywall off the studs. 48" X 96" = 4608 square inches or that much force 4608 pounds of force pulling on the each sheet of sheet rock. If you do vent it out please send us any pictures of the resulting aftermath.

John

[Tony]

John is right, it can be very dangerous to vent outside, but it is possible with suitable care.
I vent my bench down a large storm water drain that is conveniently close.

[1960FL]

Not joking here, I put a mirror up on the wall by my bench so i can see who is coming up behind me as i actually find that the ear muffs, (sound protection) help keep me be more focused during testing with better concentration on what is happening in the port. Believe it or not you can here the slight changes in the port even with the headset on, I/E like when using the FlowSticals.

JMO

Rick

[Tony]

Hearing strange port noises is one thing, motor scream or air roar coming out of the bench is just useless noise.
There may also be neighbours and family to think about.

If you have ever lived next door to a wanna-be rock band drummer, or bagpipe student, you would know what I mean.
Or some crazy loon with a home dyno.
Hahaha.............

[Malvin]

When I was at Bruce AKA PTS Head Quarters I was impressed in how actually quoit Bruce flow bench is when it is running his has 8 vacuum motors.

My flow bench is very loud when the air is being sucked down through the flow bench even when only running just 6
vacuum motors when I have 10 motors running that's all hear is air rushing & when I have 16 motors running its super
loud . My flow bench will pull my basement door closed it pulls air from upstairs hard .

[rwdford]

Yes if venting the air outside then good ventilation to let the air in/out the other direction is essential, I am thinking that venting the "exhaust" air outside is going to make quite a large difference in noise reduction on its own for intake testing, about venting the air outside I think it will be fine but if not I could always run the air into a large tank which would act like a simple exhaust silencer

For exhaust flow testing there is not a lot that can be done but most benches spend 70%+ of the time in intake mode so no worries there

I can only imagine the effort that goes into "sound proofing" dyno rooms and their exhaust exit without restricting flow, pretty essential I imagine with a NA engine running at 8 to 10K in the next room

[Tony]

Yes if venting the air outside then good ventilation to let the air in/out the other direction is essential, I am thinking that venting the "exhaust" air outside is going to make quite a large difference in noise reduction

It certainly will.
And if you are looking for sound absorbing material, humble carpet is pretty hard to beat on a cost effectiveness basis.

[Malvin]

Tony
And if you are looking for sound absorbing material, humble carpet is pretty hard to beat on a cost effectiveness basis.

What about all those sparks coming from those vacuum motors ??