Patent GB-1105521-A (GB)
Title: Improvements in or relating to closed-cycle gas turbine plant
IPC: F02C1/00
Filed: 1963-10-18
Abstract: 1,105,521. Gas turbine power plant; turbines. L.W. BAMFORD. Jan. 14, 1965 [Oct. 18, 1963], No.41208/63. Headings F1G, F1Q and F1T. A plant comprises a power turbine in a closed gas or vapour circuit including a compressor and a heat exchanger element, an open gas circuit including a combustion chamber and a heat exchanger element disposed after the combustion chamber to transfer heat to the heat exchanger element in the closed circuit, and means for transferring part of the heat of compression of the gas or vapour in the closed circuit to the gas in the open circuit at a point prior to its entry into the combustion chamber. A closed circuit 1, Fig. 1, having argon or other monatomic inert gas such as neon, krypton, xenon or helium as the working fluid includes turbines T 1 , T 2  driving centrifugal or other type compressors C 1  to C 4  and electric generators 19, Fig. 2. Heat and interstage reheat for the circuit 1 is supplied from an open circuit 3 across a heat exchanger 5. Circuit 3 includes a pump P 1  supplying air to a combustion chamber F 1 , the hot products passing through the heat exchanger 5 to a second combustion chamber F 2  and a turbine T 4  driving pump P 1 . Pre-heating of the air entering combustion chamber F 1  is effected by passing the air around paths, represented by a-b, in the casings of turbines T 1 , T 2  and by heat rejection from closed cycle 1 across heat exchanger 6. A second closed circuit 2 absorbs the heat of compression of compressors C 2 , C 3  in closed circuit 1 across heat exchangers 9, 10 and rejects heat to the air in open circuit 3 across heat exchanger 11 after the fluid in circuit 2 has been compressed by compressors C 5 , C 6  and expanded through a turbine T 3  driving these compressors. The working fluid of circuit 2 may be the same monatomic gas as used in closed circuit 1, or may be carbon dioxide or other gas. A second open circuit 4, including an air pump P2 driven by a turbine T 5 , also absorbs heat from closed circuit 1 across heat exchangers 7, 8, driving gases for the turbine being supplied by combustion chamber F 3 . A baffle system including banks of thermo-couples TC 1 , TC 2  is mounted downstream of turbines T 4 , T 5 , respectively, to utilize the exhaust energy. The thermo-couples charge an accumulator A which may supply energy to electric starting motors S 1 , S 2  or may be paralleled with the generators driven by the turbines T 1 , T 2 . Fig. 2 illustrates the arrangement of the components of the plant on a base 13. The turbines T 1  to T 3  are mounted on separate shafts, the shafts of turbines T 1 , T 2  each carrying a gear 17 which meshes with a gear on a common cross-shaft 18 driving generators 19. Turbine T 3  is geared to turbine T 2  by a shaft 20. Compressors C 5  and C 6  are mounted at one end of and coaxially with the turbine T 3 , and the compressors C 1 , C 2  and C 3 , C 4  are similarly disposed in relation to the turbines T 2  and T 1  respectively. The compressor casings are thermally insulated by lagging. Heat exchangers 5 and 11 are mounted in a high temperature bank (22), Fig. 3 (not shown) and the remaining heat exchangers 6 to 10 are mounted in a lower temperature bank 23. The gas passes from the high temperature bank (22) to the turbines T 1 , T 2  through thermally insulating ceramic nozzles. In modifications, open circuits 3, 4 may be combined, or closed circuit 2 may be eliminated, the heat of compression being transferred directly from closed circuit 1 to open circuit 3 across a heat exchanger. In further modifications, heat exchangers 6 to 10 are eliminated and the heat of compression of circuit 1 is absorbed and transferred to the open circuit 3 by a refrigeration circuit or a magneto-thermoelectric system. The latter system includes reversed thermo-couples and electromagnets supplied from the generators 19. A pressure sensitive diaphragm is connected through an electric relay to a supply pump associated with each of the closed circuits 1, 2 to maintain the gas pressure in the circuits.