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).
Use of 7 m.m. square radiator tubes compared to round tubes, including performance and cost.
| Identifier | ExFiles\Box 105\1\ scan0093 | |
| Date | 20th October 1930 guessed | |
| -2- we use 7 m.m. square tubes expanded horizontally only, and arranged with bulges for turbulence we shall have a radiator that is about 10° C. better than our present standard and one that will not be so expensive as the 6 m.m. tube. It appears that the sq. tube will always be more expensive than the equivalent round tube, but some expense can be saved by avoiding sizes below 7 m.m. It is possible that we may be able to improve the round tube still further and we are making tests in this direction. He/RH.{R. Hollingworth} | ||