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).
Investigating a 'roar' sound on a Goshawk 11 engine.
| Identifier | WestWitteringFiles\K\September1923\ Scan51 | |
| Date | 20th September 1923 | |
| R.R. 403 (40 H) (SL 42 13-7-23). J.H. D.{John DeLooze - Company Secretary} ORIGINAL EXPERIMENTAL REPORT. COPIES TO: R.CJ. BJ. WOR.{Arthur Wormald - General Works Manager} By.{R.W. Bailey - Chief Engineer} E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} EP.{G. Eric Platford - Chief Quality Engineer} PN.{Mr Northey} OY. Expl. No. X.4229 X.4580 REF. Hs{Lord Ernest Hives - Chair}3/LG20.9.23. OBJECT OF TEST. To investigate the 'roar' on Goshawk 11. by means of the R.A.E. Electrical Indicator. TESTER. W. A.{Mr Adams} Robotham. CONDITIONS. The tests were carried out on the Bench for various engine conditions as enumerated below. SUMMARY OF TEST. INVESTIGATION OF ROARING ON GOSHAWK 11. BY MEANS OF THE R.A.E. ELECTRICAL INDICATOR. The peculiarity of pressure building up in the cylinder on the exhaust stroke was observed when obtaining the standard Goshawk Indicator diagram with standard exhaust system. It will be noticed on this diagram that when the inlet valve opens there is a positive pressure of about 5 lbs./sq. in. in the cyl. It is apparent, therefore, that there will be a discharge of gas into the induction pipe at this point on the cycle. The following experiments were undertaken to determine whether there was any connection between this and the engine 'roar' which appears at 2000 r.p.m. Information with regard to the 'roar' was that it occurred at a speed of from 2000 to 2500 r.p.m., that the roar was present with the ignition switched off or with the contd:- | ||