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).
Engine cylinder temperature readings using a thermocouple, including test conditions and a table of results.
| Identifier | WestWitteringFiles\P\October1926-November1926\ Scan021 | |
| Date | 1st October 1926 guessed | |
| contd :- -2- ARRANGEMENT OF THERMO COUPLE. DIAGRAM LABELS: CYL. WALL Ni Fe GALVANOMETER THERMOMETER COLD JUNCTION Temperature readings were taken at the following places :- A.{Mr Adams} 1.875 inches from the top of the cylinder bore. B. The top of the cyl. skirt - not water cooled. C. The bottom of the skirt. The engine was run at 2500 r.p.m. at about 3/4 full load or developing about 78 HP. The total heat flow to the cooling water would be somewhere about 4000 B.T.U's/min. but no actual readings were taken at the time of the test. The compression ratio was 4.1 to 1. The following results were obtained and the diagram shews more clearly the places where the temperatures were recorded. TABLE: | Posn. | R.P.M. | Approx. H.P. | Wall temp. °C. | Average water temp. °C | Oil temp. °C | |---|---|---|---|---|---| | A.{Mr Adams} | 2500 | 78 | 80 | 75 | 70 | | B. | 2750 | 68 | 126 | 75 | 71 | | C. | 2500 | 78 | 121 | 75 | 68 | The thermal conductivity of cast iron being usually taken as .037 per B.T.U/min/sq.in/°F.{Mr Friese} the thickness of the metal being contd :- | ||