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 distribution and the performance of the standard E.A.C. hot-spot.
| Identifier | ExFiles\Box 72\4\ scan0066 | |
| Date | 12th July 1923 | |
| R.R. 493A (40 H) (SL 42 12-7-23). J.H.D. -2- EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}/AGL1/L.G1(6)123 (1) DISTRIBUTION. From consideration of the petrol consumption and power output at low speeds with the standard induction system, and normal heat supply to hot-spot, it shows that the induction pipe is reasonably good. But at the same time at low speeds full load the torque fluctuates, or the engine 'builds up'. The torque can be made to remain steady if the heat supply to the hot-spot is increased by obstructing the exit of the exhaust gas from the silencer but at the expense of a slight fall in torque. Without any heat supply to the hot-spot, the extreme cylinders (1 and 6) are weak and the power of the engine is reduced by about 24% at 500 r.p.m. accompanied by very erratic running. At 2000 r.p.m. the power drop (without heat) amounts to 3.6%. (2) PERFORMANCE OF THE STD. E.A.C. HOT-SPOT. The two pipes connecting the ends of the induction pipe with the boiler were disconnected from the boiler and led to two bottles, in which the petrol precipitated in the induction pipe was collected and measured. Consequently, the boiler was not in operation and all the heat from the exhaust gases passing through the hot-spot was available for evaporating the wet petrol spray on passing the throttle. Under these conditions an average of 1.22 pts/hr. were collected with the most economical setting of the carburetter. This amounts to approx. 5½% of the petrol supplied to the carburetter. The amount precipitated may amount to as much as 12½% of the petrol contd:- | ||