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).
Recent cooling trials of a 20/25 HP engine in a light tank.
| Identifier | ExFiles\Box 25\1\ Scan027 | |
| Date | 6th September 1932 | |
| r4688. To R.{Sir Henry Royce} from E.{Mr Elliott - Chief Engineer} E.3/HP.6.9.32. c.c. Sgr. Wcr. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} F.{Mr Friese} Mx.{John H Maddocks - Chief Proving Officer} Re trials of 20/25 RR. Engine in light Tank. In connection with the recent cooling trials on the 20/25 Tank carried out at Woolwich, we wrote and asked if we might have particulars of the data acquired in the final test. Captain Payne who was in charge of the cooling side of the tests has now sent us a print of TC.1192 and asks that this information be treated as confidential. The tank was tested in the static condition with part of the transmission removed so that a shaft could be used for coupling the engine to a dynamometer. The tank successfully complied with what the War Office call their "Tropical cooling specification" in which it is assumed that the air temperature is 100° Farenheit. To do this we fitted a powerful built up steel fan, similar in design to the Silver Ghost pattern and triple Vee belt drive, as two belts would not take the drive without stretching. A print of TC.1192 is attached and gives the information in terms of temperature difference between exterior air and top water temperature and between exterior air and oil temperature. An oil cooler is included in the installation. All the figures given are for the worst condition of operation, that is to say, with the tank fully closed down with full load consistently maintained on the engine. It will be understood that temperature conditions immediately improve if the tank is opened up. To avoid the boiling point it was necessary | ||