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).
Four different radiator tube designs for testing purposes.
| Identifier | WestWitteringFiles\C\January1919\ Scan0 | |
| Date | 4th January 1919 | |
| Mr Clarke Exp: dept COPY. ORIGINAL. To BY.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} Copy to CJ. " " EH. 3 W.O.F 4th. January, 1919. R2/G4119. RECEIVED JAN 4 1919 RE RADIATORS. X. 3456 Your memo with reference to radiators to hand. I have just suggested that tubes with round ends may be found to form a stronger metrix than those with hexagon or square ends. If bonding wires are needed, then we consider square tubes only can be adopted. This leaves us with four radiators to test - (1). 10 m/m tubes with expanded ends. (2). 10 m/m tubes with ferrules. (3). 9 m/m square tubes, formed into blocks and bonded with bonding wires at 45° to the horizontal. (4). 9 m/m square tubes, similar to (3) but with bonding wires horizontal and vertical. The 9 m/m square tube is intended to be approximately equal in area to the 10 m/m round tube. The square tube, however, should have very large radii in the corners so that small variations in the size of this radius will not have much effect on the strength of the metal in the corners of the tubes. The square tubes can be tested placed diamond-ways and also placed squarely. The bonding wires would then be diagonal and square to suit. The bonding wires, if they run through to the end of the tanks, should be made of wire having high tensile strength, and the same co-efficient | ||