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).
Tests to determine the amount of heat picked up in Phantom III cylinder head exhaust port jackets.
| Identifier | ExFiles\Box 94\3\ scan0187 | |
| Date | 22th April 1937 | |
| To E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} 3403 Rm{William Robotham - Chief Engineer}/Std.8/JH.22.4.37. Report on tests to determine amount of heat picked up in Phantom III cylinder head exhaust pat Jackets. As a result of previous test figures taken on a Phantom III engine, (see report Rm{William Robotham - Chief Engineer}/Std.15/AP.22.4.37.) it was observed that the heat to jacket water/litre of displacement (or per B.H.P.) was considerably higher on the Phantom III than on the Bentley or 25/30 H.P. engine. This was suspected to be due to the amount of water jacketting sorrounding the exhaust ports which is a feature of the Phantom III design. In order to verify this, a Phantom III cylinder head was cast with the exhaust port water jackets separated from the main water space of the head by the thickness of a metal wall - this was done by modification to a standard core etc. Further, bosses were cast on the exhaust port jackets in order to permit the fitting of unions so that water could be fed through the ports. This head was fitted to an engine on the test bed the port jackets were connected up in series and a supply of water was fed from the rear of the cylinder head through the ports. This flow was measured by means of a vessel supported on scales and the water was then allowed to run to waste. The temperature rise of the water was measured by means of glass thermometers inserted in the feed pipe before entering the ports and after leaving the ports. All piping between these thermometers ( and for a short distance on each side of them) was lagged with asbestos). Readings of temperature rise and water flow through port jackets were then taken over a range of engine speeds from 1,000 to 4,250 R.P.M. all at full throttle of course. Conclusions. Attached sheet (1) shows a curve of heat to water of the exhaust ports of one cylinder head and also deduced curve of total heat picked up by exhaust port jackets for complete engine. | ||