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).
Modifications and design ideas for Phantom silencers.
| Identifier | WestWitteringFiles\N\October1925-December1925\ Scan14 | |
| Date | 1st October 1925 | |
| R.R. 235A (10C-T) (S.H. 159, 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 ORIGINAL TO HS.{Lord Ernest Hives - Chair} FROM E.{Mr Elliott - Chief Engineer} Copy to Cl.BY. [Strikethrough] re. PHANTOM SILENCERS. E1/M5. 10. 25 X8230 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 pepperpot, and which would save weight and work. He suggested that this tube might possibly be in aluminium. 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 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. [Stamp: RECEIVED] E.{Mr Elliott - Chief Engineer} [Signature] | ||