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).
The performance of a Potts' oil cooler, including test results with temperature readings at various mileages.
| Identifier | ExFiles\Box 1\4\ B001_X 100a-page215 | |
| Date | 11th February 1933 | |
| X4057 To Hs.{Lord Ernest Hives - Chair} From GWH.{George W. Hancock - Head Chateauroux} Hotel de France, Chateauroux, France, 11.2.33. Re: 3 PER. 11. We fitted the Potts' oil cooler yesterday morning. The results are a 25% efficiency in cooling, with an improvement in oil consumption. The results show that we get very little cooling effect from our ribbed bottom half, although it has been fully exposed. I am also of the opinion that our oil pump delivers too much oil. In this I mean that the oil is circulated too quickly and has not time to be cooled down. The results of the cooler verify this statement. It shows that the oil has not time to warm up in this case. We should therefore be better off with a less efficient pump. I have tried one experiment previously by reducing the outlet hole by half, but did not get very satisfactory results. Reducing the inlet would probably be more effective. The temperatures shown with the Potts' cooler are, delivering from the pump, and after passing through cooler to bearings:- Miles | Oil Temp. to bearings. | Oil temp. from sump. | Water | Air. 25 | 72 | 75 | 78 | 9 50 | 72 | 75 | 72 | 12 75 | 69 | 71 | 71 | 12 100 | 70 | 74 | 78 | 11 125 | 62 | 65 | 80 | 11 150 | 64 | 69 | 73 | 10 175 | 76 | 80 | 80 | 10 200 | 70 | 73 | 80 | 10 225 | 78 | 79 | 78 | 10 250 | 78 | 80 | 77 | 10 Average Speed 47.62 mph. [Diagram showing a pump, cooler, and engine part with labels 'Pump', 'Cooler', 'T1', 'T2'] GWH.{George W. Hancock - Head Chateauroux} G.W.H. Hancock | ||