Patent GB-954896-A (GB)
Title: Improvements in or relating to turbine mechanisms
IPC: F01D1/34
Filed: 1960-05-03
Abstract: 954,896. Turbines; gas turbine plant; jet propulsion plant. L. L. POHL. May 3, 1960 [May 5, 1959], No. 15543/60. Headings FIG, F1J and FIT. A turbine device comprises a casing having inlet and outlet passages for flow therethrough of a stream of fluid medium, a single blade being rotatably mounted in a chamber within the casing about a longitudinal axis passing through the centre of gravity of the profile section, the axis of rotation being transverse to the direction of flow of the fluid medium and the chamber having diamatrically opposite portions which are formed as arcs of a common circle. The inlet passage is constricted in the direction of flow and the blade is caused to rotate by reason of the aerodynamic lift, the dynamic and the static pressure forces acting successively on the blade. The blade may be of thin double-convex shape or of flattened S-shape or thin rhombic shape. The basis of the invention is illustrated in Figs. 5, 6, and 7 in which the symmetical blade is shown rotatably mounted within a casing C having an offset inlet passage at the right and a discharge passage at the left. Rotation of the blade between positions 1-1 and 2-2 shown in Fig. 4 is caused by reason of the aerodynamic effect of the fluid stream acting on the blade, the lower surface of the blade being subjected to an increase in pressure and the upper surface to a reduction in pressure. Between the positions 2-2 and 4-4 the rotational effect on the blade is produced by the dynamic effect of the pressure fluid impinging on the blade. Between the positions 4-4 and 5-5 the rotational effect on the blade is produced by the difference in the static pressure on the upper and lower surfaces of the blade. Similar effects are produced during rotation of the blade from the 180 to 360 degrees positions. The blade may be twisted along its length; also the two edges of the blade may be curved so that the blade is of elongated S-section. The fluid flow passage is substantially closed when the blade is in the position indicated at 3-3. In the embodiment shown in Fig. 10 the inlet and outlet passages 10, 15 merge smoothly with the blade chamber 14 which is formed between two arcuate surfaces. In this embodiment, the fluid passage is substantially closed during movement of the blade from position 6-6 to position 7-7. In Fig. 15 a two-stage arrangement is shown, the outlet duct from the first stage forming the inlet duct to the second stage and being so disposed that the second stage blade rotates in the opposite direction to the first stage blade. The two blades in this arrangement are in phase, that is each blade is simultaneously in line with either the lower or the upper surfaces of the inlet and outlet passages. In the two-stage arrangement shown in Fig. 16 the two blades are out of phase, the second stage blade B 2  lagging 30 degrees behind the first stage blade B 1 . Turning moment diagrams for one and two stage turbines are given, those for the latter being both for turbines with and without phase difference. In the three stage turbine shown in Fig. 19 the casing is made hollow to permit the flow of cooling fluid which is finally discharged into the exhaust stream issuing from the final turbine stage. The blade may also be made hollow to permit flow of cooling fluid therethrough, for example, in Fig. 21 cooling fluid is supplied through the hollow trunnions by which the blade is rotatably mounted, the hollow space within the blade being divided into two parts by a partition W. The cooling fluid finally discharges through outlets or where it may produce a rotational effect. Other arrangements are shown for example a two stage turbine in which the blades rotate in the same direction, a flat four stage turbine, and a four stage turbine in which the blade axes are disposed on a circular pitch. A complete engine is shown in Fig. 29, the compressor Cr being driven by the turbine assembly Te (shown in end view in Fig. 30) and supplying air to the combustion equipment Bn, gases from the latter being divided into two streams each of which flows through three turbines Te 1 , Te 2 , Te 3  or Te<SP>1</SP> 1 , Te<SP>1</SP> 2 , Te<SP>1</SP> 3  disposed on a semicircular pitch. An arrangement is described in which exhaust gas from the turbine assembly passes through a heat exchanger for pre-heating air discharged from the compressor. In the gas turbine jet propulsion engine shown in Fig. 39, the compressor C R  is driven by an assembly of four turbines disposed in X-form. In the gas turbine propeller engine shown in Fig. 40, the turbines are again disposed in X-form, two oppositely disposed turbines being interconnected to drive the air compressor C R  and the other two being interconnected to drive the airscrew P R . Fig. 43 shows a two-stage turbine Te suitable for driving an automobile, exhaust gases from the turbine passing through a heat exchanger Rg to preheat the air being supplied to the combustion equipment Bn.