GB935268A - Improvements in and relating to power plants employing internal-combustion engine gas-generators - Google Patents

Abstract

935,268. Gas turbine plant. ALAN MUNTZ & CO. Ltd. Dec. 29, 1961 [Jan. 25, 1961], No. 2974/61. Class 110 (3). [Also in Group XXIX] A power plant employing one or more internalcombustion engine gas-generators of turbine or free piston type, supplying power to a prime mover, such as a turbine, has in addition an auxiliary radial inward flow turbine, having a variable nozzle area, which is driven by power gas from the gas-generators derived from a pipe coupling the gas-generators to the prime mover in which the pressure changes as the load on the prime mover changes. A battery of free piston gas-generators G1, G2, G3, G4 delivers gas to a common gas manifold 10. A pipe 11 feeds gas from the manifold 10 to a main turbine 12 driving a ship's propeller 13 through a reduction gear 14. Gas is also fed from the manifold 10 through a pipe 15 to the auxiliary turbine 16 driving an electrical generator 17. Gas from pipe 15 enters the turbine 16, Fig. 3, at an inlet 23 and is directed by nozzle blades 24 into a rotor 25. Each of the blades 24 is pivotally mounted upon the stator and is connected by a a lever 26 and a link 27 to a pivot pin 28 fixedto a control ring 29 which is rotatable through a small angle about the rotor axis relatively to the stator. Rotation of the ring 29 serves to increase the nozzle area, a blade rotation of 24 degrees requiring a rotation of 6 degrees of the ring 29. The control mechanism, Fig. 3, for rotating the ring 29 employs an oil relay which is controlled by two separate operating pressures, namely the control oil pressure derived from the speed governor 19 of the turbine 16 applied at 31 and the gas supply pressure at the inlet 23 which is applied through a pipe 32. The control oil pressure is fed by the pipe 31 into a cylinder 33 containing a piston 34 and a spring-loaded bellows 35. The pressure in the pipe 32 is applied to a cylinder 36 containing a piston 37 and a spring-loaded bellows 38. The pistons 34, 37 are connected by a link 39 to which is pivoted a lever 40 coupled to the ring 29 and to the rod of the main relay piston 42 operating in a cylinder 43 by a link 41. The slide valve control member 44 of the relay is pivoted to the lever 40. Oil is admitted to the relay at a port 45 and passes out at 46. Movement of the pistons 34, 37 thus rotates the ring 29. To reduce the sensitivity of the control mechanism at high gas pressures, a variable rate spring may be fitted in the gas pressure bellows 38. Alternatively, Fig. 4, the lower end of the lever 40 is coupled by a link 47 to a floating lever 48. The upper end of the lever 48 is coupled to the piston 34 and its lower end bears against a cam lever 49 having its lower end mounted on a fixed pivot 50 and its upper end coupled to the piston 37. Hence as the gas supply pressure increases the lever ratio alters and the sensitivity is reduced.