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).
Installation tests concerning air space and the formation of steam pockets in 'F' engine cylinder jackets.
| Identifier | WestWitteringFiles\V\December1930-February1931\ Scan168 | |
| Date | 27th January 1931 | |
| To. R.{Sir Henry Royce} Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} Rg.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} By.{R.W. Bailey - Chief Engineer} lp.{Mr Lappin} ORIGINAL Hs{Lord Ernest Hives - Chair}/TAG.1/WE.27.1.31. X4509. INSTALLATION TESTS. AIR SPACE AND FORMATION OF STEAM POCKETS IN 'F' ENGINE CYLINDER JACKETS. Steam pockets form in "F" engine cylinder jackets to such an extent that the quantity of water displaced necessitates a header tank of considerable dimensions to accomodate the displaced water. Steam pockets form irrespective of header tank position to varying degrees, but the worst condition is when the tank is in a position similar to that of the 'Hart' and 'Fury' machines, i.e. immediately behind the engine on approximate level with the cylinder heads. AIR SPACE. The installation of "F" engines in the aircraft mentioned above is such that when the tail of the machine is resting on the ground the water level in the cylinder jackets does not completely cover the liners of certain cylinders and the extent of which this occurs is governed by the position and height of the header tank relative to the cylinder blocks. Tests have been made to find out the variation of the water level for varying angles of engine inclination and its effect on the functioning of the water system. The result of the tests show that:- (a) The formation of steam pockets in the cylinder jackets of an "F" engine are so great that it necessitates the use of a very large header tank to hold the water displaced by the steam formed. (b) That steam pockets form in the jackets even when the temperature of the water in the header tank is as low as 40 to 45°C. (c) That unless all the air in the cylinder jackets is driven out, the formation of steam pockets is greatly aggravated and water is displaced very rapidly. (d) That under normal running conditions maintaining a temperature of 80°C outlet, 53% of the total volume of water in the cylinder jackets is displaced by steam, using a 'Hart' or 'Fury' tank. | ||