advice for engine dyno cell

1) Heavy walls, say a brick cavity wall are your best bet. Typical sound levels will be around 100 dBA at one metre.

2) main frequency is at firing order, so for a V8 that is rpm/60*8/2 Hz. There is a lot of broadband noise and harmonics as well.

3) don't know about other dynos, our noise dyno had extraction at all 4 corners.


Cheers

Greg Locock

Bryan,

We are just putting the finishing touches on a 2000 HP dyno cell. We recieved a lot of help with our goal of a quiet cell we could use any time day or night in the industrial complex without angry neighbors. First I doubt you will contain exhaust noise in the cell without great mufflers, search the web they are out there they are big, heavy and expensive, they will exit the cell. Next an engineer friend offered this info, 90% of the sound can escape through a 1% of area opening (walls and roof for total area). The above means build the cell like a boat, air tight (air system asside). The walls for our cell are sheet-rock, with a room inside a room, the inner walls floated on sound clips, the outer room isolated from the inner room, again search the web for info on sound rooms. Dual doors, with sound seals, dual isolated glass (Lexan), sound caulking details details details. The air system was handled by others, the short form is insulated duct work oversized and no straight line of sight paths for sound to excape without first hitting insulation. I can also suggest looking at some dyno cells and talk with the opperators most will show you what they have done.

Good luck.

Dave