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).
Summary of the first 100 hours of contract running on a C.I. 4-stroke unit.
| Identifier | ExFiles\Box 133\3\ scan0040 | |
| Date | 28th February 1939 | |
| Rm{William Robotham - Chief Engineer}/Ed.{J. L. Edwards}5/MH.{M. Huckerby}28.2.39. SUMMARY OF FIRST 100 HOURS CONTRACT RUNNING ON C.I. 4-STROKE UNIT. Introduction. The period covered is from 25.7.30 to 16.6.31. Range of Investigation. (1) Nozzle Development. (2) Swirl Tests. (3) Valve and Injection timing. (4) Fuel line capacity. (5) Mechanical Efficiency. (6) Volumetric Efficiency. Conclusions. (1) Approximately the same performance can be obtained with or without swirl provided the nozzles are adjusted to suit the altered conditions. (2) Fuel penetration appears extremely important, and rather high injection pressures are required. To secure sufficient atomisation, a rather more divergent spray is necessary under no swirl conditions than when swirl is employed. (3) The volume of the fuel line should be kept as small as possible or low speed performance suffers, eight stroking occurring under idling conditions. (4) The best method of promoting swirl is by partially masking the inlet seats, any other method having an adverse effect on the volumetric efficiency. (5) A rather prevalent trouble on valves employing differential valve opening is leakage of fuel past the valve stem. This, unless kept very small, has an adverse effect on the power, and is similar in effect to using too small a diameter pump plunger. | ||