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).
Design and testing of a Phantom I evaporative cooling system and its special radiator.
| Identifier | ExFiles\Box 182\M21\ img083 | |
| Date | 12th April 1933 | |
| -3- Ha/Pav.6/KT.12.4.33. Detailed Report. The system is shown diagrammatically in sketch No.1 and A.R. Sch.375. The radiator is of special design, the block being used as a steam condenser. Water flows from the header tank down the sides of the radiator tube block to the water circulating pump by which it is pushed through the cylinder block and back into the header tank where steam separation takes place. The steam flows down a passage to the bottom of the radiator matrix and percolates up the tube block until condensed, any excess steam blowing off through a vent at the top of the radiator. The condensate drains into a hotwell and after passing through a non-return valve is returned to the main circulating system by an injector pump as per A.R.Sch.375. General Data. Engine - Phantom I evaporatively cooled. Capacity of water system - 5 galls. 1 pint. Water circulation by standard pump 12-15 galls/min above 1500 R.P.M. Injector Dimensions. Pressure Nozzle dia. .1375 Venturi Throat dia. .201" Road Speed with special large tyres:- at 1000 RPM. - 27 mph. on top gear. 1300 RPM. - 35 mph. (cruising conditions) 2100-2200 RPM - 57-60 mph. (max.speed). Tests. The main water pump pressures were first measured and found to be very low. With the water boiling the pressure (above static) varied directly as the engine speed up to 2 1/4 lbs/ sq.in. at 1900 RPM., above which speed it remained constant. The injector was tested on a rig and found to require a minimum pressure of 1 1/2 lbs/sq.in. (above static) to pump against a delivery head of 18". Tests were then carried out to find the maximum pressures which could be produced by the main water pump at different speeds and to measure the actual head at the main pump inlet against which the injector had to deliver. Two .375" dia. restriction washers were placed in the cylinder block inlets | ||