860,073. Centrifugal and axial-flow fans and pumps; gas-turbine jet-propulsion plant; turbines. RENSSELAER POLYTECHNIC INSTITUTE. June 12, 1957, No. 18514/57. Classes 110 (1) and 110 (3). [Also in Group XXVIII] Fig. 4 shows a supercharger or pump in which a driving fluid is supplied through a pipe 34 to a rotor 36, which is rotated by the fluid as it is exhausted as propulsive jets 40 through nozzles 37. Each jet 40 forms a pseudo blade rotating with the rotor and inducing the flow of a secondary fluid from an inlet 35. Guide blades 43 are set at an angle corresponding to the direction of flow of the jets 40, while guide blades 44 on the opposite side of a central partition 31 are set at an angle corresponding to the direction of flow of the secondary fluid. Since each fluid tends to flow through those guide vanes which are set at an angle offering the least obstruction to its flow, the driving fluid passes through guide vanes 43 to a volute 41, while the secondary fluid passes through guide vanes 44 to a volute 42, the separated fluids being discharged through the respective discharge ducts 32 and 33. In the pump shown in Fig. 10, driving fluid from a pipe 92 passes as propulsive jets through skewed passages 93 in a rotor 91, causing rotation of the rotor. The jets form pseudo blades which impel secondary fluid from an inlet 97a to a volute 87 by way of openings 94 in the rotor. The driving fluid is discharged to a volute 86 through openings 95 in an outer wall of the rotor. The two fluids are discharged through ducts 88, 89 which may be separate as shown or may alternatively merge into a common duct in which the fluids are mixed. Fig. 8 shows an axial-flow fan, compressor or pump in which the driving fluid is supplied through a pipe 67 to a rotor 66 and issues as a propulsive jet through a single inclined orifice 70 to cause rotation of the rotor. The jet passes through a casing 68a in the form of a helical pseudo blade 71, impelling a secondary fluid through the casing 68a from an inlet 69. The casing may be of cylindrical form or, as shown, may taper towards the outlet to accelerate the flow to provide favourable energy transfer from the driving fluid to the secondary fluid. A jetpropulsion engine, Fig. 6, comprises a rotor 59 which is rotated by driving fluid supplied through a pipe 61 and discharged through propulsive orifices 60. The jets 64 of driving fluid form pseudo blades which induce axial flow of the surrounding air. Rings 57, 58 can be displaced rearwardly by electric or hydraulic actuators 63 so that the jets 64 are deflected forwardly instead of rearwardly as shown, to reverse the direction of the propulsive thrust. The rings 57, 58 may also be tilted about an axis perpendicular to the longitudinal axis to alter the direction of thrust by disturbing the symmetry of the pseudo blade pattern. Instead of being supplied under pressure through a pipe 61, the driving fluid may be supplied by a pump or gas generator mounted within casing 56. A simpler jet-propulsion engine comprises an arrangement similar to that shown in Fig. 8, but with the casing omitted; more than one discharge orifice may be provided. In a further jet-propulsion engine, Fig. 9, a duct 81 having a curved inner surface 82 is supported on the engine casing 76. The driving fluid, issuing as pseudo blades from the rotor orifices- 80, impels the surrounding air through the duct 81 as a propulsive jet. Fig. 12 shows a jetpropulsion engine or gas generator in which combustion gases pass through orifices in a rotor 107, causing rotation of the rotor and forming pseudo blades which impel air through a passage 109. The combustion gases then pass through guide vanes 113 which are inclined in the direction of flow of the gases, and then through a reheat combustion chamber 118 to a discharge duct 119. Means may be provided for varying the area of duct 119. The air impelled through passage 109 passes through guide vanes 112 which are inclined in the direction of flow of the air, and enter a combustion chamber 111. The resultant combustion gases pass through the rotor 107, as previously described. Ports 131, the opening of which may be variable, may be provided to allow some air to pass direct into the chamber 118. Vanes 113 may be omitted, for the same purpose. The reheat combustion chamber 118 may be omitted. The arrangement according to Fig. 12 may be used as a gas generator to supply driving gas to the engine shown in Fig. 6. In the embodiment shown in Figs. 16 and 17, an endless belt 147 passes over pulleys at opposite sides of a flow duct which is of generally rectangular cross-section in planes parallel to the belt. Driving fluid is supplied to transverse channels 143, 144 and passes through inclined slots 153 in the belt as propulsive jets which drive the belt and form pseudo blades which impel secondary fluid along the flow duct from an inlet 140. The belt may be driven by an electric motor. In the jet-propulsion engine shown in Figs. 20 and 21, driving fluid from a pipe 166 passes through a Venturi 161. The Venturi is surrounded by an annular space divided into compartments by curved partitions 164a. The pressure drop occurring in the vicinity of the throat of the Venturi is communicated through ports 162 to the interiors of the compartments and transferred through ports 163 to points near the outlet of the Venturi which are angularly displaced relative to the corresponding ports 162. The suction exerted at the ports 163 causes a corresponding angular displacement of the stream of driving fluid. The resultant rotating pseudo blades induce flow of the surrounding air at 170.