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).
Radiator efficiency tests and methods for determining cooling system performance.
| Identifier | ExFiles\Box 24\4\ Scan286 | |
| Date | 21th November 1924 guessed | |
| -2- 20 M.P.H. | Condition of car. | Increase or decrease in Rad. efficy: | |---|---|---| | | 20¼" matrix. | 23¼" matrix. | | Removing Fan. | Decrease 29% | Decrease 29.5% | | Opening shutters. | Increase 7.6% | Increase 7.4% | | Opening louvres. | " 7.6% | " 7.4% | METHOD B The actual equivalent of this test climbing an indefinitely long hill whose gradient is just sufficient to absorb the full power of the engine on top gear at any required road speed. In point of fact, unless the radiator is capable of dealing with the heat generated, this test cannot be employed as if the water boils no value of δT can be obtained; by the other method, however, the value of the system can be obtained no matter how low it may be. To obtain the absolute value of any system from either of the two tests, that is the B.Th.U dissipated by the system per min. per F° difference between the mean water temp. and the air, it is only necessary to know For 'A' :- Water equivalent of the system. This has been obtained by weighing cyl. block and radiator, allowing for the crankcase and determining the water capacity. For 'B' :- Heat given out to the cooling water by the engine on full throttle at various r.p.m. This has been obtained on the bench. Of the two tests, the second is very much the simplest and quickest. It is also the simplest better in practice contd :- | ||