EXHAUST DEVICE AND COMBUSTION TURBINE COMPRISING SAME

Technical Field

The present utility model relates to an exhaust device and a combustion turbine comprising the exhaust device.

Background Art

For a combined cycle power plant, the temperature and mass flow rate of gas exhausted from a combustion turbine significantly affect the efficiency and performance of the combined cycle. It can be learnt from aerodynamic analysis that a horizontal exhaust structure is conducive to

effective releasing of energy from the exhausted gas.

However, for a combustion turbine of a hot-end-drive construction, a diffuser for vertical exhaust is required, which necessarily increases the exhaust pressure drop. Many methods have been proposed to minimize such an exhaust pressure drop.

Summary of the Utility Model

The present utility model provides an exhaust device which can solve the above-mentioned and/or other technical problems and a combustion turbine comprising the exhaust device .

In one exemplary embodiment, an exhaust device

comprises: a housing, comprising an exhaust end cavity and a closed end cavity; an inner diffuser, arranged in the housing and located between the exhaust end cavity and the closed end cavity; an outer diffuser, configured to

surround the inner diffuser and to define a gas flow passage that guides gas to flow in an axial direction of the housing into the exhaust end cavity and the closed end cavity; and a centrifugal guide member, arranged at a position, corresponding to the gas flow passage of the outer diffuser, on an inner wall of the closed end cavity, such that gas is guided to flow in a direction along the inner wall of the closed end cavity when the gas flowing in a direction towards the inner wall of the closed end cavity from the gas flow passage of the outer diffuser reaches the centrifugal guide member. Therefore, gas can be guided to flow in a direction along the inner wall of the closed end cavity, and a gas flow with a uniform flow velocity can be formed in the closed end cavity.

The centrifugal guide member comprises a first wing portion and a second wing portion, the first wing portion and the second wing portion are arranged on the inner wall of the closed end cavity, one side of the first wing portion and one side of the second wing portion intersect with each other to form a ridge, the other side of the first wing portion and the other side of the second wing portion are connected to the inner wall of the closed end cavity. The first wing portion and the second wing portion are respectively in the shape of a continuous curved surface which extends from the ridge to the inner wall of the closed end cavity and is concave towards the inner wall of the closed end cavity. The first wing portion and the second wing portion are mirror-symmetrical in shape with respect to the ridge. The distance between the other side of the first wing portion and the other side of the second wing portion continuously increases as the other side of the first wing portion and the other side of the second wing portion extend in the axial direction away from the outer diffuser. The centrifugal guide member according to an exemplary embodiment can guide gas exhausted from the gas flow passage into the closed end cavity to flow in a direction along the inner wall of the closed end cavity, instead of flowing towards the inner wall of the closed end cavity and colliding with the inner wall and thus

generating a vortex.

The ridge extends in an axial direction, and has a height relative to the inner wall of the closed end cavity that increases continuously as the ridge extends in the axial direction away from the outer diffuser. Therefore, a gas flow with a uniform flow velocity can be formed in the closed end cavity.

The exhaust device comprises a plurality of

centrifugal guide members, the plurality of centrifugal guide members being arranged in a circumferential direction at positions, on an inner wall of the closed end cavity, that correspond to the gas flow passage of the outer diffuser .

According to another exemplary embodiment, a

combustion turbine comprises the exhaust device as stated above .

The exhaust device and the combustion turbine

according to the exemplary embodiments can effectively improve the flowing of gas with a simple structure as described above and at a relatively low cost; therefore, production is easy, or modifications may be made on the basis of existing combustion turbines (for example, SGT- 400), so as to obtain the exhaust device and the combustion turbine according to the exemplary embodiments.

Brief Description of the Drawings

The following drawings are only to schematically describe and explain the present utility model, and do not limit the scope of the present utility model, in which:

Fig. 1 is a perspective view showing an exhaust device according to an exemplary embodiment; Fig. 2 is a sectional view showing an exhaust device according to an exemplary embodiment;

Fig. 3 is a perspective view showing a centrifugal guide member arranged on a housing according to an

exemplary embodiment;

Fig. 4 is a sectional view showing a centrifugal guide member according to an exemplary embodiment; and

Fig. 5 is a sectional view showing a centrifugal guide member according to an exemplary embodiment.

Description of Reference Signs:

100 housing 300 inner diffuser 500 outer diffuser 700 centrifugal guide member

110 exhaust end cavity 130 closed end cavity

510 gas flow passage

710 first wing portion 730 second wing portion 750 ridge

Detailed Description of Embodiments

In order to facilitate clearer understanding of the technical features, objectives and effects of the present utility model, the particular embodiments of the present utility model now are described with reference to the drawings .

Fig. 1 is a perspective view showing an exhaust device according to an exemplary embodiment, and Fig. 2 is a sectional view showing an exhaust device according to an exemplary embodiment.

As shown in Figs. 1 and 2, the exhaust device

according to an exemplary embodiment may comprise a housing 100, an inner diffuser 300, an outer diffuser 500 and a centrifugal guide member 700. Such an exhaust device can be contained in a combustion turbine, for example, the exhaust device according to an exemplary embodiment can be used in a combustion turbine of a combined cycle power plant. The housing 100 can form an outer casing of the exhaust device. The housing 100 may define spaces,

including spaces defining an exhaust end cavity 110 and a closed end cavity 130, for example. In general, the housing 100 may be made of metal. An upstream portion of the housing 100 may be connected to a turbine cylinder and an exhaust cylinder, and a downstream portion thereof may be connected to a waste heat boiler via a pipeline.

The inner diffuser 300 may be arranged in the housing 100 and located between the exhaust end cavity 110 and the closed end cavity 130. The inner diffuser 300 can be connected to an inner exhaust flow channel of a turbine, so as to exhaust the gas from the turbine to the waste heat boiler .

The outer diffuser 500 may be configured to surround the inner diffuser 300, so as to form a gas flow passage 510 allowing gas to flow through between an inner wall of the outer diffuser 500 and an outer wall of the inner diffuser 300. The outer diffuser 500 can be connected to an outer exhaust flow channel of the turbine, so as to exhaust gas from the turbine to the waste heat boiler via the gas flow passage 510.

As shown in Fig. 2, gas flow passing through the gas flow passage 510 may be exhausted to the exhaust end cavity 110 and the closed end cavity 130. Therefore, in order to prevent gas exhausted to the closed end cavity 130 via the gas flow passage 510 from flowing towards an inner wall of the closed end cavity 130 and/or generating a vortex in the closed end cavity 130, and according to an exemplary embodiment, the centrifugal guide member 700 may be

arranged at a position, corresponding to the gas flow passage 510 of the outer diffuser 500, on an inner wall of the closed end cavity 130. Such a gas flow path can be formed by arranging the centrifugal guide member 700, namely, when gas flowing in a direction towards the inner wall of the closed end cavity 130 from the gas flow passage 510 of the outer diffuser 500 reaches the centrifugal guide member 700, the centrifugal guide member 700 can guide the gas to flow along the inner wall of the closed end cavity 130 in a direction towards the exhaust end cavity 110.

Fig. 3 is a perspective view showing a centrifugal guide member arranged on a housing according to an

exemplary embodiment, Fig. 4 is a sectional view showing a centrifugal guide member according to an exemplary

embodiment, and Fig. 5 is a sectional view showing a centrifugal guide member according to an exemplary

embodiment .

As shown in Figs. 3-5, the centrifugal guide member 700 may comprise a first wing portion 710 and a second wing portion 730. The first wing portion 710 and the second wing portion 730 may be arranged on the inner wall of the closed end cavity 130, and one side of the first wing portion 710 and one side of the second wing portion 730 intersect with each other to form a ridge 750. The other side of the first wing portion 710 and the other side of the second wing portion 730 may be connected to the inner wall of the closed end cavity 130. The centrifugal guide member 700 comprising the first wing portion 710 and the second wing portion 730 can be made of metal, and can be combined with the inner wall of the closed end cavity 130 by a combining process such as fusion welding.

In order to form the gas flow path as described above, the first wing portion 710 and the second wing portion 730 may be respectively in the shape of a continuous curved surface extending from the ridge 750 to the inner wall of the closed end cavity 130 and being concave towards the inner wall of the closed end cavity 130. As shown in Figs. 3 and 4, the first wing portion 710 and the second wing portion 730 may be symmetrical in shap with respect to the ridge 750, for example, in mirror symmetry .

As shown in Fig. 4, the distance between the other side of the first wing portion 710 and the other side of the second wing portion 730 may continuously increase as the other side of the first wing portion 710 and the other side of the second wing portion 730 extend in the axial direction away from the outer diffuser 500.

As shown in Fig. 5, the ridge 750 formed by one side of the first wing portion 710 intersecting with one side o the second wing portion 730 may extend in an axial

direction of the housing 100, and may have a height relative to the inner wall of the closed end cavity 130 increasing continuously as the ridge 750 extends in the axial direction away from the outer diffuser 500.

As shown in Figs. 3 and 4, the first wing portion 710 and the second wing portion 730 may be symmetrical in shap with respect to the ridge 750, for example, in mirror symmetry .

As shown in Fig. 4, the distance between the other side of the first wing portion 710 and the other side of the second wing portion 730 may continuously increase as the other side of the first wing portion 710 and the other side of the second wing portion 730 extend in the axial direction away from the outer diffuser 500.

Figs. 3-5 show that an exhaust device according to an exemplary embodiment may comprise one centrifugal guide member 700; however, the exemplary embodiment is not limited thereto. For example, the exhaust device may comprise a plurality of centrifugal guide members 700. In this exemplary embodiment, the plurality of centrifugal guide members 700 can be arranged in a circumferential direction at positions, on an inner wall of the closed end cavity 130, corresponding to the gas flow passage of the outer diffuser.

Thus, the centrifugal guide member 700 according to an exemplary embodiment can guide gas exhausted from the gas flow passage 510 into the closed end cavity 130 to flow in a direction along the inner wall of the closed end cavity, instead of flowing towards the inner wall of the closed end cavity 130 and colliding with the inner wall and thus generating a vortex. In addition, because of continuous increasing of the height of the ridge 750, a gas flow with a uniform flow velocity can be formed in the closed end cavity 130.

The exhaust device and the combustion turbine

according to the exemplary embodiments can effectively improve the flowing of gas with a simple structure as described above and at a relatively low cost; therefore, production is easy, or modifications may be made on the basis of existing combustion turbines (for example, SGT- 400), so as to obtain the exhaust device and the combustion turbine according to the exemplary embodiments.

It should be understood that the description is described according to the embodiments; however, it does not mean that each embodiment only comprises one

independent technical solution, and such a description manner of the description is merely for clarity. A person skilled in the art should take the description as a whole, where the technical solution in each embodiment can also be suitably combined to create other implementations which a person skilled in the art can understand.

The above description is merely schematic specific embodiments of the present utility model, rather than being intended to limit the scope of the present utility model. Equivalent variations, modifications and combinations made by anyone skilled in the art without departing from the concept and principle of the present utility model should all fall within the scope of protection of the present utility model.