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).
Letter discussing oil cooling tests for the Peregrine engine and a flywheel issue.
| Identifier | ExFiles\Box 1\4\ B001_X 100a-page208 | |
| Date | 9th February 1933 | |
| X4057 G.W.Hancock, c/o Hotel de France, Chateauroux, Indre, FRANCE. To GWH.{George W. Hancock - Head Chateauroux} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Many thanks for your notes. We can now give you a little information with regard to oil cooling. We find that the Peregrine gives nearly as much heat to the cooling water as the Kestrel aircraft engine. The higher engine speed is undoubtedly mainly responsible for this. At the moment we are taking up the view that we do not want to reduce the quantity of heat given to the oil; if we do, the parts which are at present oil cooled may overheat. Therefore, we are concentrating on finding means of cooling the oil. Our first endeavour is to reproduce road conditions on the test bed. We are proposing to put a Powerplus blower on the nose of the Peregrine, and blow air over the bottom half, and to get the right quantity of air blowing over the bottom half, we want you to take some figures for us. If you will run at constant roadspeeds of 60, 65, 70, and if you can, 75 m.p.h. until the oil temperature ceases to rise any further, you will obtain heat balance at each speed. If you will then give us the air temperature and the water temperature, we can reproduce your conditions on the test bed by blowing air across the bottom half of the crankcase with the engine running at the predetermined road speed, until we get the same results as you do. This will then enable us to try different changes of oil flow in the bottom half. Actually, at present, we think that to get the best results, the bottom half should be ribbed both internally as well as externally. We cannot understand what has happened to your flywheel period. It is interesting if it has disappeared, because the same thing happened on Per.1. The probability is that driving hard over the French roads has taken the resonance out of the body. | ||