TURBINE AND OPERATING METHOD OF THE SAME

• US 20140023478A1
• Filed: 03/07/2013
• Published: 01/23/2014
• Est. Priority Date: 07/20/2012
• Status: Active Grant

• Current Assignee: Toshiba Energy Systems & Solutions Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Tashima, Tsuguhisa, Iwai, Shogo, Tsuruta, Kazutaka, MAEDA, Hideyuki, Okizono, Nobuhiro, Sato, Iwataro, Okamura, Naoyuki
• Granted Patent: US 9,488,051 B2
• Time in Patent Office: Days
• US Class Current: 415/1
• CPC Class Codes: F01D 11/04 using sealing fluid, e.g. steam
• CPC Class Codes: F01D 25/168 for axial load mainly
• CPC Class Codes: F01D 25/26 Double casings; Measures against temperature strain in casings
• CPC Class Codes: F01D 3/04 axial thrust being compensated by thrust-balancing dummy piston or the like
• CPC Class Codes: F02C 1/08 Semi-closed cycles
• CPC Class Codes: F02C 3/34 with recycling of part of the working fluid, i.e. semi-closed cycles with combustion products in the closed part of the cycle
• CPC Class Codes: F05D 2260/61 Removal of CO2 removal of CO2 from waste gases B01D53/62

Abstract

According to one embodiment, there is provided a single-flow turbine using CO₂ as a working fluid. The turbine includes a balance piston portion configured to optimize an axial load of a rotor on a bearing with a fluid having a temperature lower than a temperature of the working fluid introduced into the turbine, wherein a flow path in which at least a part of the fluid passing through the balance piston portion is extracted from a middle part of the passing, and in which at least a part of the extracted fluid is urged to flow to a middle part of a passage where the working fluid passes and where rotor blades at a plurality of stages are provided, is formed at the turbine.

Claims

1. A single-flow turbine using CO₂ as a working fluid, comprising:

a balance piston portion configured to optimize an axial load of a rotor on a bearing with a fluid having a temperature lower than a temperature of the working fluid introduced into the turbine,

wherein a flow path in which at least a part of the fluid passing through the balance piston portion is extracted from a middle part of the passing, and in which at least a part of the extracted fluid is urged to flow to a middle part of a passage where the working fluid passes and where rotor blades at a plurality of stages are provided, is formed at the turbine.

2. The turbine according to claim 1, further comprising:

a first casing surrounding the rotor; and

a second casing surrounding the first casing,

wherein at least the part of the extracted fluid flows to the middle part of the passage where the working fluid passes and where rotor blades at the plurality of stages are provided, after passing between the first casing and the second casing.

3. The turbine according to claim 2, wherein at least the part of the extracted fluid flows to a sealing portion configured to prevent the working fluid from leaking from a gap between the rotor and a stationary portion, after passing between the first casing and the second casing.

4. A turbine operating method for use in a single-flow turbine using CO₂ as a working fluid, the method comprising:

optimizing an axial load of a rotor on a bearing with a fluid having a temperature lower than a temperature of the working fluid introduced into the turbine, by a balance piston portion; and

extracting at least a part of a fluid passing through the balance piston portion from a middle part of the passing, and urging at least a part of the extracted fluid to flow to a middle part of a passage of the working fluid where rotor blades at a plurality of stages are provided.