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).
Test report on the effects of high water flow and low jacket temperatures on detonation in a Kestrel six-cylinder engine unit.
| Identifier | ExFiles\Box 54\4\ Scan089 | |
| Date | 20th July 1935 | |
| 84659. To Sg. {Arthur F. Sidgreaves - MD} From Hs {Lord Ernest Hives - Chair} /Ryce. Hs {Lord Ernest Hives - Chair} /Ryce.5/MJ.20.7.35. c. to Rg. {Mr Rowledge} c. to Wor. {Arthur Wormald - General Works Manager} c. to By. {R.W. Bailey - Chief Engineer} c. to Lr. {Mr Ellor} x2965. KESTREL SIX CYLINDER UNIT. EFFECT OF HIGH WATER FLOW AND LOW JACKET TEMPERATURES ON DETONATION. It has been considered a possibility that some of the detonation effects observed in the cylinder head have been due to inadequate water flow or steam pocketing at the part of the head so attached. This was thought to be a possible reason why only one or two cylinders of a block should exhibit destructive signs of detonation while the remainder of the cylinders were completely unaffected. A test was therefore made using the maximum obtainable water flow and low jacket temperatures with the engine run under conditions of detonation which are known to be destructive to the cylinder head and joint ring when operating under standard water-cooled conditions. With this object five additional water inlets through the exhaust side core plug holes were connected to the town mains. Two additional ½” dia. water outlets were also taken from Nos.2 and 4 inlet side core plug holes. The existing outlets and inlets were left untouched. The general conditions were as follow - Two Piece Cylinders - K.41218, K.41096. Supercharger - Kestrel F.S. with full width rotor. Water Pump - K.33098 standard. Water Outlet - 30° to 40°C. Water flow - Approx. 120 galls/Min. i.e. about 2½ times normal. R.P.M. - 2600. Boost - 2 lbs/sq.in. at 85°C. Detonation - 30 ft. inc. to 50 ft. for the last 20 mins. Running time - 4 hours. RESULTS OF TESTS. After 4 hours running a gas leak occurred at No.3 cyl. joint ring. Examination showed that only No.3 cylinder was affected and there was no trace of attack in any of the other cylinders. In the affected cylinder the head was badly attacked on the side adjacent to No.4 cyl. only. The upper joint ring was badly attacked and a piece has been burnt away. The lower joint ring was untouched. The piston was slightly attacked. All attacks were in the same position. | ||