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).
Patent specification document for improvements relating to the propulsion of aircraft.
| Identifier | ExFiles\Box 147\2\ scan0198 | |
| Date | 18th May 1935 | |
| PATENT SPECIFICATION Application Date: May 18, 1935. No. 14575/35. 456,980 Complete Specification Left: April 20, 1936. Complete Specification Accepted: Nov. 16, 1936. PROVISIONAL SPECIFICATION Improvements relating to the Propulsion of Aircraft I, FRANK WHITTLE, Flight Lieutenant, R.A.F., of “Blackamoors”, Harston Road, Trumpington, Cambridgeshire, British Subject, do hereby declare the 5 nature of this invention to be as follows:— This invention relates to that type of engine for aircraft in which air is taken in, compressed, heated, and expanded, 10 and expelled sternwards to provide thrust by fluid reaction, part of the expansion being utilised to perform the work of compression, and the remainder producing the velocity from which the reaction 15 is obtained. That part of the work of expansion which supplies the power for compression taking place through a turbine which drives a compressor of the centrifugal type. 20 The object of this invention is to provide an improved engine of this type. According to the invention, a propulsion engine for aircraft consists primarily of one or more centrifugal compressors, a 25 turbine, a combustion chamber, and a propelling nozzle or nozzles, and auxiliary apparatus to be described, the whole being suitably housed. The arrangement is such that the 30 compressor continuously draws large quantities of air from the atmosphere through an opening preferably situated in the nose of the nacelle or fuselage in which the engine is mounted, and com- 35 pressing it passes it to a combustion chamber through which it flows continuously, receiving heat as it does so from the combustion of a suitable fuel, such as oil or petrol, the heating thus 40 taking place at sensibly constant pressure. From the combustion chamber the air passes through a nozzle or nozzles to the buckets of a suitable turbine, preferably a two row Curtis type, or simple De Laval 45 type. The expansion through the turbine is only sufficient to enable it to drive the compressor, and a second expansion takes place through a nozzle or nozzles situated at the aftermost portion of the nacelle or 50 fuselage, or at any other point suitable for the purpose. The turbine is carried on the same shaft as, or suitably geared to the compressor. [Price 1/-] Means may be provided for any or all of the following:— 55 (a) Controlling the fuel supply. (b) Governing the speed of the rotating units. (c) Starting. 60 (d) Governing the mass flow of air. (e) Supplying air to a hermetically sealed cockpit. (f) Fuel pumps and the like. (g) Any necessary instruments. 65 In more particularly describing the invention in one form suitable for propelling aircraft both at or near ground level and at altitudes much above those attainable with existing means of propulsion, 70 the compressor is of the type described in a co-pending application No. 14,285/35 (Serial No. 456,976), that is to say, it has air intakes on both sides of the impeller casings; it has an impeller 75 with a large number of webbed and ribbed radial blades, and preferably also two rings of intake guide blades which may be extensions of the radial blades. It also has a compound diffuser arrange- 80 ment. The said compound diffuser consisting of an inner bladeless portion of considerable radial dimensions, and an outer ring of stationary diffuser blades. Various modified forms of this type of 85 compressor may be used, for instance it may have a diverging volute in addition to or instead of the stationary diffuser blades. A single combustion chamber is formed 90 to be continuous with the discharge passage of the compressor, and consists of a large chamber, the long axis of which lies approximately in a plane parallel to that of rotation and is curved to be 95 approximately concentric with the compressor and/or turbine shaft. The shape of the combustion chamber in section is such as to give the most compact arrangement in conjunction with other com- 100 ponents, whilst being suitable for its purpose. The cross section of the combustion chamber decreases in size towards both end and is shaped to form a smooth entry from the discharge pipe of the compressor 105 and a smooth entry to a single turbine | ||