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).
Instructions on using a nomogram for Condor, Eagle, and Falcon engines with examples and notes on its limitations.
| Identifier | ExFiles\Box 77\5\ scan0127 | |
| Date | 17th May 1918 | |
| Contd. -2- EFC1/T17.5.18. Condor, Eagle, and Falcon engines are indicated by circles and examples of the use of this nomogram in the cases of the Condor and Falcon are shown. In the Condor case the speed is supposed to be 1600 R.P.M. and the brake mean pressure 120 lbs/sq.inch. The intersection of the correct line with the brake horse power scale gives the corresponding brake horse power, namely, 518. In the case of the Falcon, the speed has been taken at 2000 R.P.M. the horse power as 262.5 and the brake mean pressure corresponding to these quantities as found by drawing the correct line, would be 120 lbs/sq.inch. It is hoped that this nomogram may be useful for quick determinations of this nature. It will be noticed that the working volume scale covers a complete logarithmic range, namely 300 to 10 X 300, so that in any case in which the working volume does not lie between these two figures the diagram can still be used by multiplying or dividing by 10 and considering 10 engines or 1/10 of an engine at a time, with corresponding increases or reductions in the brake horse power. The only disadvantage of this diagram as regards accuracy is that the brake horse power scale is necessarily rather close. This however, is inherent in the nature of the diagram and cannot be avoided except by increasing the size of the whole diagram. EFC. | ||