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).
Investigation into the value of the redistributor induction system (DES.1653) for Goshawk engines.
| Identifier | ExFiles\Box 179b\3\ img298 | |
| Date | 6th March 1933 | |
| ORIGINAL To. From Ha/Fmr. Ha/Fmr.5/WJ.6.3.33. x4658 GOSHAWK ENGINES. REDISTRIBUTOR INDUCTION SYSTEM. DES.1653. An investigation of the value of the redistributor type of induction pipe to DES.1653 which is fitted to Goshawk engines, has been carried out in order to prove whether any advantage is gained as regards the redistribution of the mixture. The results are also comparative with the Kestrel S. engine with a view to shewing that the later design of the Goshawk engine is not retrograde as regards fuel economy. The induction system DES.1653 as fitted to the Goshawk engine consists of four branch pipes on the cylinder blocks, which are grouped, to feed from a common junction. This junction which is at the end of the outlet extension pipe from the supercharger, has an annular groove internally, which collects wet or heavy fuel into a well. Projecting from the collecting well are four short pipes or nozzles, which extend into the entrance of each branch pipe, and the wet fuel collected in the well is distributed evenly to each of the main branch pipes via the nozzles. The investigation tests in the form of a series of specific consumption loops at constant speed, with various throttle openings, in which the mixture control is weakened progressively from its richest position down to the weakest point at which the engine will run. This form of test indicates the value of the distribution by the lowest specific consumption at which power is maintained, and also shews the point of maximum economy, which depends entirely on the cylinders which receive the weakest mixture. Goshawk engine No.1 was used for the tests which were made at fixed throttle positions equivalent to 200-350-500-750 B.H.P. and full throttle at constant engine speed of 2500 R.P.M., the conditions being identical for each series of tests i.e., with and without the redistributor. The fuel used was the standard D.T.D.134 for throttle positions up to 500 BHP. and 20/70/10 plus 4 cc's. (Avn/Ben/Meth) for the higher powers. K.L.G. 744 14mm. plugs and P.4 oil was used. | ||