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).
Maximum indicated pressure tests to investigate engine detonation and ramming action in induction pipes.
| Identifier | ExFiles\Box 179b\4\ img072 | |
| Date | 20th April 1933 | |
| -2- Ha/Yng.4/MJ.20.4.33. Cont'd.{John DeLooze - Company Secretary} change in working conditions. The engine was run at 2500 RPM./485 BHP. in the fully strong and weakest possible mixture strength positions and exhaust flame temperatures taken at each exhaust port by means of a furnace-type thermo couple. This test failed since the maximum temperature difference recorded was only 20ºC. (3) Maximum indicated pressure tests. In a final endeavour to trace any definite signs of excessive detonation occurring in No.3 cylinder rs{Sir Henry Royce's Secretary}, maximum indicate pressure tests were taken in each cylinder by means of a Dobbie McInnes Farnborough Electric Indicator gauge and a reed-type indicator valve. These tests taken at 2500 RPM/485 BHP. confirmed the results obtained by tests (1), the pressure recorded in No. B.3 cylinder, viz. 375/425 lbs/sq.in. being 50/90 lbs/sq.in. less than the average pressure recorded for the cylinder block. Conclusion. The foregoing tests not only failed to verify the theory of any "ramming" action taking place in the induction pipes affecting distribution and volumetric efficiency of No.3 cylinders but if they can be regarded as positive tests they amply demonstrate that such an action is non-existent. Ha/H.R.Young. | ||