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).
Detonation tests carried out on detachable head cylinders for the Kestrel engine.
| Identifier | ExFiles\Box 179\2\ img098 | |
| Date | 31th December 1931 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Yng. c. to Secr. c. to Rg.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} ORIGINAL DETACHABLE HEAD CYLINDERS - KESTREL - The detachable head type cylinders fitted to Kestrel II.S.25 have recently been subjected to an endurance run detonating in order to prove out the construction. Features of these cylinders in which we are particularly interested are the construction of the joint at the top of the liner and the ability of the head to keep cool. If these points prove satisfactory then this type of liner construction might be used in place of our present method thereby eliminating the troubles due to distortion now experienced. -Conditions of Test. Engine II.S.25 with 2 piece cylinder construction. Fuels - D.T.D.134 and Shell aviation. Water Outlet 100°C. Engine run so that the detonations could be heard 100 ft. away. -Tests Carried Out. Primarily it was necessary to fix the standard of detonation due to the difference in the 'detonation note' of the detachable head cylinders and the standard type (See report ref. Hs{Lord Ernest Hives - Chair}/Dor.{Mr Dorey}4/WJ.15.10.31.) The engine was therefore opened up at a constant speed of 2000 r.p.m. with the water outlet temperature at 75°C until the detonation could be heard at a distance of 100 ft. from the engine. This, with D.T.D.134 fuel, was obtained with 6.0"Hg boost. The fuel was changed to D.T.D.134 + 3 ccs TEL/gal. and it was found that a gain in power of approx. 7% resulted from the suppression of detonation by the use of the antidetonating fuel. A test of 80 mins. duration was then run off at 2000 r.p.m. on D.T.D.134 with the water outlet temperature at 100°C and the engine detonating as before. A further test of 80 mins. duration was then carried out on Shell aviation fuel with the same conditions of speed detonation and water temperature. The boost pressure with the plain aviation fuel to obtain the required intensity of detonation was only 1.5"Hg. After the above running (2hrs.40 mins.) the power began to fall off rapidly and the engine was shut down. Investigation showed that the gas joint ring between the | ||