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).
Optimal design and placement of radiator louvres and thermostats.
| Identifier | WestWitteringFiles\F\February1921\ Scan36 | |
| Date | 1st February 1921 | |
| To CY. & HS.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} -2- RG{Mr Rowledge}/G1S/2/21 Contd. was quite capable of doing the work of operating well balanced shutters, and therefore the oil pressure relay system was an unnecessary complication. We still have the impression that the best fitting that can be put on a car is direct acting large size thermostat working the louvres directly. That the louvres should be in front of the bonnet is desirable, but we do not think the difference would be quite as marked as would make the fitting of them in this position an absolute necessity. Our first reason for fitting them behind the radiator was that the appearance would not be marked, and the whole thing would look cleaner, and the bonnet would look slightly longer, which in our newer engines would be a decided advantage. We are having a set of hand-operated louvres fitted in both positions to find out whether there is any serious objection to the louvres being behind the radiator. There is the slight advantage that in the extremely cold weather a muffle can be used on the front of the radiator, having only a small adjustable opening to permit of sufficient cooling air to pass. This would be scarcely possible with the louvres in front, as the muffle might interfere with the action of the louvres. In conclusion, we agree that a set of hand shutters and a thermometer will be an immediate solution of the difficulty, and that the thermostat bypass had better not be introduced, but that we had better proceed as mentioned in other memos, of endeavouring to standardise a satisfactory set of shutters operated by the thermostat, and which will be capable of being easily fitted to cars at present being built. R.{Sir Henry Royce} | ||