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).
6th order vibration characteristics and damping for a 12-cylinder V-engine.
| Identifier | ExFiles\Box 178\4\ img099 | |
| Date | 24th May 1932 | |
| a.{Mr Adams} From Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} c. to Sd. c. to W.R. c. to Rg.{Mr Rowledge} c. to Ev.{Ivan Evernden - coachwork} X.634. X.4024. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}1/MA.24.5.32. 12 CYLINDER ENGINE. Replying to R.S/11.5.32 concerning the severity of the 6th order vibration for a 60 Vee engine, we had not meant to give the impression that the vibration would be bad. As suggested in Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}3/MA.24.2.32 we think that the amplitude of the 6 per rev vibration for a 12 cylinder 6250 cc engine with a 60 Vee angle will be about 5/6 that of the P.II half period. It should therefore be easy to damp out. Evidence of this is provided by the many 12 cylinder cars on the market on which no period can be felt and which have only medium efficient dampers. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||