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).
Comparison of cooling system performance with different radiator matrices and alterations.
| Identifier | ExFiles\Box 24\4\ Scan283 | |
| Date | 21th November 1924 guessed | |
| -2- easily compared as they might be. We have however calculated from the above figures the various alterations in the systems :- METHOD 'B'. 30 M.P.H. 20¼" matrix. Condition of car. | % improvement on standard. Shutters open. | 8.3% Louvres open. | 10.2% Top panels removed. | 15.3% Side panels removed. | 19% 30 M.P.H. 23¼" Matrix. Condition of car. | % improvement on standard. Side shutters. | 7.1% Shutters side & top. | 10.2% Louvres. | 8.7% Side panels off. | 19.8% For these tests the bonnet of the larger radiator had four shutters cut in the top. The shutters in the side were exactly the same size for both matrices. Increase cooling obtained from 23¼" matrix all closed at 30 M.P.H. over 20¼" matrix. 9.7% In method 'B' it was necessary to use two different cars for the two radiators. It is quite possible that the heat given out to the cooling water by the respective engines was not identical in each case. Comparing the two radiators we therefore prefer method 'A' which eliminates this factor. Values of respective Fans by this method. 40/50 HP. fan removed cooling efficiency drops 21.2%. Hispano " " " " " 8.9% N.B. In order to prevent the car boiling with the fan off in the 40/50 H.P. case the test had to be run with the maximum ventilation (i.e. bonnet sides off) air would therefore be able to pass freely through all portions of the matrix. This possibly contd :- | ||