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 detailing claims for an axial flow turbine, compressor, or pump.
| Identifier | ExFiles\Box 147\2\ scan0206 | |
| Date | 16th January 1939 | |
| 8 511,278 The predominant condition which is to be applied is that vwbs = M/r—where M = angular momentum of fluid about the axis of the machine. 5 The foregoing examples illustrate the manner in which the angles defining blade formation in accordance with this invention may be ascertained with considerable accuracy. It will be appreciated, how- 10 ever, that the actual flow of the fluid may depart angularly from the angles so ascertained by small amounts. The blade angles thus ascertained may therefore be modified in practice by such small 15 amounts to allow for such difference as will be understood by those skilled in the art. Having now particularly described and ascertained the nature of my said inven- 20 tion and in what manner the same is to be performed, I declare that what I claim is:— 1. An axial flow turbine, compressor, pump or like rotary power conversion 25 machine operating with compressible viscous fluid, wherein are employed blades which are so shaped that their effective entry and/or leaving angle or angles and pitch vary progressively at increasing 30 radial distance along an individual blade in such a manner that the said effective angle or angles and pitch at each said radial distance correspond substantially to the motion of the operative fluid rela- 35 tive to said blade at each said radial distance upon the basis that the velocity of said fluid varies inversely with radial distance, when the machine is operating under normal design conditions. 40 2. An axial flow turbine, compressor, pump or like rotary conversion machine, wherein are employed blades which are so shaped and positioned as to conform to the condition that, when the machine is 45 operating under its normal design conditions, in flowing through the said blades, the operative fluid, being compressible viscous fluid, has its angular momentum about the axis of the machine changed 50 from one value which is substantially uniform before engaging the blades, to another value which is also substantially uniform after leaving the said blades, whilst the axial velocity of said fluid is 55 substantially uniform both before entering and after leaving the said blades, through the magnitude of the axial velocity is not necessarily the same before entering and after leaving the said blades. 60 3. An axial flow turbine, compressor, pump or like rotary power conversion machine, wherein are employed upon the rotor, blades so shaped and positioned that the effective entry angles of said blades conform to the condition specified in Claim 1. 65 4. An axial flow turbine wherein are employed upon the stator, blades so shaped and positioned that the effective leaving angles of said blades conform to the con- 70 dition specified in Claim 1. 5. An axial flow compressor or pump wherein are employed upon the stator, blades so shaped and positioned that the effective leaving angles of said blades con- 75 form to the condition specified in Claim 1. 6. An axial flow compressor or pump wherein are employed upon a stator, blades so shaped and positioned that the effective entry angles of said blades conform to the 80 condition specified in Claim 1. 7. A turbine according to Claim 1, in which the blades are employed upon the rotor such that the ratio u/vw at the roots of said 85 blades is of a value of 0.5 or slightly greater and in which the degree of reaction increases towards the tip and is substantially zero at the root. 8. A turbine according to Claim 1, 90 wherein the operative fluid is admitted through stator blades forming a nozzle ring, these blades being such that, substantially, the fluid is discharged therefrom at maximum angles A which vary 95 radially according to the formula A = tan^-1 (rva/M). 9. A turbine according to Claim 1, wherein the operative fluid is admitted through stator blades forming a nozzle 100 ring, and wherein the rotor blades are such that, at all radii r, the minimum value of the entry angle B = tan^-1 (va / (M/r - u)). 10. A turbine according to Claim 1, wherein the operative fluid is admitted 105 through stator blades forming a nozzle ring, and wherein the rotor blades are such that, at all radii r, the maximum value of the leaving angle C = tan^-1 (va / u). 11. A turbine in which are combined 110 the characteristics of Claims 8, 9, and 10. 12. Machines according to any previous Claim, in which a peripherally enclosed space or clearance exists between the planes in which lie adjacent edges of 115 rotor and stator blades, equal axially at least to one quarter, and preferably at least a half the chord of the rotor blades. 13. A turbine according to Claim 2, of 511,278 9 the velocity compounded type, having a plurality of rows of rotor blades on the wheel with intervening stator rows, so arranged that only the last row of rotor 5 blades creates purely axial discharge, whilst the angular momentum of the fluid is uniform in each space between rotor and stator blades. 14. An axial flow turbine, compressor, 10 pump or like rotary power conversion machine operating with compressible viscous fluid, constructed and arranged to operate in accordance with the basic principles hereinbefore stated and substan- 15 tially described in the foregoing Specification with the aid of the accompanying drawings. Dated this 16th day of January, 1939. For the Applicant, F.{Mr Friese} J.{Mr Johnson W.M.} CLEVELAND & COMPANY, Chartered Patent Agents, 29, Southampton Buildings, Chancery Lane, London, W.C.2. Leamington Spa: Printed for His Majesty’s Stationery Office, by the Courier Press.—1939. | ||