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).
Report discussing engine power testing methods, specifically B.HP and I.HP graphs and mechanical efficiencies.
Identifier | ExFiles\Box 113\2\ scan0028 | |
Date | 26th February 1923 guessed | |
contd:- -2- the crown wheel and pinion a correction has been made for this. A correction has not, however, been made in this graph for the fact that the throttle was closed during the decelerations and hence the results are too large. Further tests with the cut-out open have shewn that the power required to turn the engine over varies almost directly as the speed. We think, therefore, that this graph should be nearer a straight line drawn through the four points. The object of this graph was to obtain the I.H.P. The B.H.P. and I.H.P. Graphs. The B.H.P. at the clutch and road wheels is taken from bench and dynamometer tests. The I.H.P. is taken as the B.H.P. plus the power expended in turning the engine over. It is not pretended that this is accurate, but it gives us an approximate method of obtaining mechanical efficiencies, which we shall be able to obtain accurately when the R.R. Indicator is in action. The Mechanical Efficiencies.are calculated directly from the B.H.P. and I.H.P. curves. (Preliminary tests of this description only.) HS{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||