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).
Phantom II cooling tests, measuring the air temperature rise through the radiator and the effect of a louvred bonnet on under-bonnet air pressure.
| Identifier | ExFiles\Box 16\2\ Scan036 | |
| Date | 7th September 1931 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey} C. Sg.{Arthur F. Sidgreaves - MD} C. Nor. E.{Mr Elliott - Chief Engineer} C. De. RV. X7250. Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey}1/AD17.9.31. PHANTOM II COOLING TESTS. x766. x7260. (1) Air Temperature rise through radiator. We have carried out tests to measure the air temperature rise through the matrix under road conditions. In order to get as accurate results as possible the tests were carried out on a car from which the bonnet and undershields had been removed, in addition a heat shield was fitted between the fan and the engine and the recording thermometers were placed about one inch in front of and behind the radiator matrix. The results show a maximum rise of 23.25°C. at 20 M.P.H. falling off to 20.5°C. at 60 M.P.H. with a water temperature of 85°C. By decreasing the water temperature 18°C. the temperature rise is reduced to 18.5°C. at 20 M.P.H. and 15.25°C. at 60 M.P.H. (2) Bonnet ventilation. In order to record the increase in bonnet ventilation due to using a louvred bonnet, tests were carried our in which the air pressure under the bonnet was measured. The car used for the tests was fitted with standard undershields and fan, and the radiator was fitted with 6 x 7.5 mm. matrix tubes with four indentations per tube. Records of the pressure existing in four different places were taken, two on either side of the engine midway between the bonnet side hinge and the bottom of the side panel, and level with the front and rear sliding bonnet shutters. From the results obtained it appears that using a louvred bonnet reduces the pressure under the bonnet by approximately 40%. Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey} | ||