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).
The effect of different coolants upon the cylinder head temperature of a Kestrel six-cylinder engine unit.
| Identifier | ExFiles\Box 54\4\ Scan104 | |
| Date | 9th August 1934 | |
| Hs {Lord Ernest Hives - Chair} /Ryce.5/MJ.9.8.34. KESTREL SIX CYLINDER UNIT. EFFECT OF COOLANT UPON CYLINDER HEAD TEMPERATURE. In view of the apparently more severe conditions obtained on main engines running Glycol cooled, head temperatures have been measured running with water, steam and Glycol. Position of Thermo Couples. Thermo couples were inserted in the gas starter plugs, and near the top joint rings, in cylinders 3, 4, and 6 (Fig.4). These couples will, it is thought, record the temperature of the gas starter plug about 0.075" from surface, and the metal temperature adjacent to the top joint ring. This temperature will probably be near the hottest part of the ring circumference owing to the absence of coolant near the couple. TESTS CARRIED OUT. The engine was run at various inlet temperatures at 2500 RPM. + 8 "Hg. boost and a constant fuel consumption with the two coolants. The gas starter plug couples in cylinders 3 and 6 were then interchanged and the tests repeated. To eliminate trouble from exhaust gases blowing back on to the couples it was found advisable to run open exhaust. RESULTS OBTAINED. It will be seen that :- From Fig.1. (a) By changing from water to Glycol at the same temperature the couples read 43°C. more. (b) The increase in temperature of the couples is only about one third that of any increase in coolant temperature. (c) The temperature evaporatively cooled is only from 8°C. to 15°C. more than the corresponding water cooled temperature. From Figs. 2 & 3. (a) The results obtained are in themselves consistent but may vary from day to day by about 15°C. (b) No.6 cylinder tends to run cooler than No.3 while No.4 is intermediate between the two. | ||