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 testing, covering fuel injection rates, swirl effects, fuel pump suction line issues, and mechanical failures.
| Identifier | ExFiles\Box 133\3\ scan0035 | |
| Date | 25th February 1939 | |
| -2- Rate of Fuel Injection. This was varied by increasing the pump plunger size from 8 m/m to 10 m/m dia., the effect being an increase in power of from 1.0 to 4.0 MEP depending on the type of nozzle used. Swirl. Some preliminary tests were made by throttling one of the inlet ports. Results are open to criticism, however, in that the volumetric efficiency is altered by the modification, somewhat obscuring the issue. The nett effect of inducing swirl by this means was a drop in power of from 1.0 to 3.0 BMEP. Swinging in Fuel Pump Suction Line. Surging is caused by the intermittent flow of fuel in the suction line and is most pronounced for small injection quantities, i.e. when major portion of pumped fuel is returned to the suction side of the injection pump. The trouble was overcome by fitting a small air chamber in the suction fuel line as close to the injection pump as possible. Mechanical Failures. Small end bush (1.250" bore) collapsed, but trouble was rectified by force feeding oil to the little end. The white-metal big end has collapsed twice since raising max. pressure to 1000 lbs/sq.in., by crumbling away on top. Rm{William Robotham - Chief Engineer}/Ed.{J. L. Edwards} | ||