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).
Engine cooling system performance, comparing Phantom I and II radiators and analyzing water circulation.
| Identifier | WestWitteringFiles\U\January1930-April1930\ Scan027 | |
| Date | 10th January 1930 | |
| -3- temperatures higher than this the delivery water to the radiator is boiling and therefore the cooling system is inadequate for other reasons. Curves (1) Hs{Lord Ernest Hives - Chair}/AJL9.1.30 shew that up to an engine speed of 3000 r.p.m. we are, on new cars, within the limit of maximum circulation, but that it would not require very much obstruction to put us outside this limit. On a separate sheet we have compared the hydraulic resistance of various radiators measured on the standard works test rig. It will be seen that with the latest large gap Phantom ll radiator we are not quite back to the freedom of V series Phantom l radiators, but very nearly so. We should say that with our anti-corrosion treatment of the cylinder water jackets we ought to compensate for this small difference. With a view to seeing how much we could restrict the water pump flow without impairing the car's cooling we carr- ied out road tests progressively reducing the size of the deliv- ery orifices to the radiator, until further reduction caused a rise in radiator temperature. The flow was then measured with these restrictions compared with standard (Graph. 4 andl Hs{Lord Ernest Hives - Chair}/AJL1.9.1.30). These shew that the circulation cannot be reduced very much. They also shew that any such restriction must not be put on the far side of a rubber connection as the back pressure built up is over 20 lbs/sq.in. at high engine speeds.(Graph. 2 Hs{Lord Ernest Hives - Chair}/AJL1.9.1.30. | ||