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 heat flow analysis under various test conditions.
| Identifier | ExFiles\Box 24\4\ Scan090 | |
| Date | 6th September 1923 | |
| R.R. 493A (40 H) (EL 42 12-7-23). J.H.,D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. page 3. Expl. No. REF HS{Lord Ernest Hives - Chair}2/L06.9.23. These curves are plotted on an H.P. base as they then give a comparison of heat flow under throttled and full load conditions for the same output. Test 3. The heat supply to the jacket water is seen to increase by decreasing the mixture strength. It is possible that a mixture over 20% weak would not cause a proportional increase in the heat flow. For a rich mixture giving approx. 4% reduction in power the heat loss to cooling water may be reduced to the extent of about 14%. Test 4. The ignition timing giving the minimum loss of heat to water is found to be that which gives the maximum torque, the heat losses increasing with extreme advance and retard. Test 5. There is very little difference between heat flow to cooling water with aluminium or cast iron pistons, (Sheet 5.) Test 6. With a badly carbonised engine less heat is conducted to the water than in the case of a clean engine. On the 'Energy Diagrams' will be seen the loss to cooling water expressed as a % of the initial petrol energy. The percentage loss is read down from the 100% line. From these results it is seen that the conditions for the minimum loss through cooling water is :- High compression engine (within limits) Rich mixture. Normal ignition. Full load. ------------ | ||