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).
Effectiveness and control mechanisms of radiator shutters.
| Identifier | ExFiles\Box 39\4\ Scan079 | |
| Date | 19th November 1925 | |
| To BJ. from Hm.{Capt. W. Hallam - Head Repairs} C O P Y. RADIATOR SHUTTERS. My criticism of the Radiator Shutter should not be taken to mean that the shutters themselves would aggravate boiling in the mountains of Scotland. Shutters can be fitted, as in the case of the Phantom, where the difference in temperature with shutters full open and without shutters is so small as to be negligible. This would not be the case if our method of fixture and controls were not positive and gave the full advantage when it was necessary to have the shutters full open. Both Paddon Bros. and Barkers shutters are controlled by Bowden wire which is not considered a reliable method of control for such a device as radiator shutters, when the full effectiveness of cooling the water in the radiator is required. As an example we have at the present time in the Repair Dept. a car fitted with Paddon shutters, and where the quadrant control limits the movement of the slats from closed to approx. 45° instead of 90°, at this angle and with the Bowden control and general design of shutter, the wind pressure will have a tendency to close still more the shutters. We have not made any tests with either Paddon Bros. or Barker shutters, and to obtain definite proof of their merits or otherwise would necessitate extensive experiments if it is necessary to prove the effect of shutters under all the different conditions when boiling may occur. (Sgd.) W.H. (Hm.{Capt. W. Hallam - Head Repairs}) | ||