From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Design modifications for the Phantom Silencer.
| Identifier | ExFiles\Box 66\2\ scan0099 | |
| Date | 10th May 1925 | |
| X. 8230 To Hs.{Lord Ernest Hives - Chair} from E.{Mr Elliott - Chief Engineer} c. to CJ. BY.{R.W. Bailey - Chief Engineer} E1/M5.10.25. RE. PHANTOM SILENCERS. Regarding your visit to WW. on Friday last, I return herewith the blue print you brought of the concentric tube silencer, with modifications made in pencil as suggested means of making the silencer for production. This is not an official LeC. drawing, but may help the matter on the way. You will remember that Mr. Royce objected to the extra weight of the concentric tube, and suggested that this tube might be cut short at the front end, which we have shewn instead of making it into a pepper-pot, and which would save weight and work. E.{Mr Elliott - Chief Engineer} suggested that this tube might possibly be in alum. Mr. Royce was inclined to think that the use of more baffles in the plain silencers with central tube only should be sufficient, but you informed him that this had proved insufficient-ly silent. E.{Mr Elliott - Chief Engineer} suggested with the use of 5 or 6 baffles in plain silencers the drilling of the holes in these baffles alter-nately, so that the gas was forced to zig-zag in its passage through the silencers. With this scheme the idea is to prevent a sound wave travelling directly through the silencer in a straight line, and also to set up eddies with the object of destroying the energy in the gas impulses. E.{Mr Elliott - Chief Engineer} | ||