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).
Fan drive improvements and bonnet ventilation to reduce boiling.
| Identifier | ExFiles\Box 24\4\ Scan238 | |
| Date | 11th September 1924 | |
| R.R. 493A (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} -3- EXPERIMENTAL REPORT. Expl. No. REF. hsl/LG11.9.24. driver has tightened the fan belt in the morning, if he runs the car at high speeds for any length of time, it will have become slack so that when he reaches a hill, the radiator efficiency has reduced considerably. All of our assumptions that the water will keep cooler on lower gear, is assuming that the fan is working efficiently; if the fan is not working efficiently, the driver will be worse off. A line of improvement which we can definitely take up is the improvement in the Fan Drive. We have recently sent a standardisation sheet round for a new Brammer type of Fan Belt which our tests in France proved requires less attention, and maintains the fan drive better than the present standard Whittle Belt. EY. has also sent a scheme through which enables us to fit a .75" fan belt instead of a .625" fan belt. Bonnet Ventilation. Bonnet ventilation is the most effective way to reduce the boiling which occurs at high speeds. There is no reason why our shutters should not be increased in size especially as the bonnet sides are now deeper. We have been carrying out tests in France at high speeds with ventilation, by removing the side panels and the top plates of the bonnet separately. The tests there shew that removing the two top plates of the bonnet and retaining the two side panels is more effective as regards reducing the water temperature than removing the bonnet altogether. contd :- | ||