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).
Performance comparison of fans driven with the same speed ratio.
| Identifier | ExFiles\Box 75\3\ scan0045 | |
| Date | 3rd February 1925 guessed | |
| EFC1/T9.2.25. -6- Contd. For a performance comparison of fans driven with the same speed ratio see sheet II, which exhibits on a fan-speed base, the power required to drive and the thrust produced for :- (1) Present standard 20 HP. fan. (2) Hispano fan. (3) Most efficient expl. 20 HP. fan. From these curves it will be seen that whereas the thrust for a given speed for the new fan is somewhat greater than for the standard, the power required to drive is still considerably less. Hence there is considerable justification for retaining the standard belt drive ratios. EFC. | ||