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).
Graph and table comparing the performance of different types of radiator cores for slow-speed cooling.
| Identifier | WestWitteringFiles\U\August1930-November1930\ Scan084 | |
| Date | 24th September 1930 guessed | |
| TYPES OF RADIATOR CORE FOR SLOW SPEED COOLING Y-Axis: H.P. DIS. PER SQ. FT. FRONTAL AREA PER 100° DIFF IN TEMP. X-Axis: AIR SPEED THROUGH MATRIX M.P.H. Diagram 'C': .078 .250 ZIG ZAG RIBBON WITH INDIRECT COOLING Diagram 'B': .405 Diagram 'A' & 'B': TUBES .250 DIA: EXPANDED TO HEXAGON ENDS Legend: DALBY 7 M.M. TUBES 4'-0" LONG, 1 M.M. GAP Table: | | WT EMPTY | WT FULL | SQ. FT. SURFACE | % FREE AIR AREA | % DIRECT | DEPTH | |---|---|---|---|---|---|---| | A | 11.0 | 15.6 | 33.8 | 61.6% | 93% | 4.0 | | B | 12.3 | 14.4 | 37.2 | 72.7% | 28.0% | 3.250 | | C | 14.5 | 18.9 | 51.5 | 64.2% | 54% | 4.0 | | ||