JPH09280073A - Fuel supply device for gas turbine combustor - Google Patents

Abstract

(57) Abstract: A fuel supply device for reducing combustion vibration in a gas turbine combustor is provided. SOLUTION: Fuel supply pipes 131, 132, 133, 134, 135 connected to a fuel manifold 12 and a combustor.
136, 137, 138, 139, 140, 141, 1
42, 143, 144, cylindrical spaces 151, 152, 153, 154, 15 having a diameter larger than that of the fuel supply pipe.
5,156,157,158,159,160,16
1, 162, 163, 164.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine, and more particularly to a fuel supply device for a gas turbine combustor in an industrial gas turbine.

[0002]

2. Description of the Related Art Generally, in an industrial gas turbine equipped with a plurality of combustors, fuel is supplied from a fuel mother tube through an arcuate or annular fuel manifold, and the fuel is distributed in the same shape around the gas turbine. It is distributed to the combustor. An example of a fuel supply device for an industrial gas turbine is disclosed in JP-A-57-122130.

An example of a pressure pulsation suppressing device which propagates through a pipeline is disclosed in Japanese Patent Laid-Open No. 62-118188, in which the pressure pulsation is attenuated between the inlet and outlet of one pipe.

[0004]

In an industrial gas turbine provided with a plurality of combustors having the same shape, pressure pulsations generated by fluctuations in heat generation of each combustor are sent from the fuel supply device to each combustor. The fuel supply amount may fluctuate, and due to this influence, a feedback loop may be formed in which the fluctuation of heat generation in the combustor becomes larger.

Further, in the industrial gas turbine, the fuel is planned to be evenly distributed to the combustors, and the branch fuel supply pipes connected from the fuel manifold to the combustors have the same shape. It Therefore, the pressure transmission characteristics of each fuel branch pipe are the same. Furthermore, since each combustor in the gas turbine has the same shape, the pressure oscillations sent from each combustor are sent to the manifold while having almost the same characteristics. Therefore, when a standing wave is formed in the fuel manifold, the pressure oscillation from each combustor that resonates in the fuel manifold increases the pulsation of the standing wave and changes the fuel supply amount to each combustor. . For this reason,
For that reason, combustion oscillations in the combustor are increased. In addition, due to standing wave vibrations in the fuel manifold,
May cause mechanical destruction of structures.

An object of the present invention is to provide a fuel supply device which prevents resonance of pressure oscillation of each combustor in the fuel manifold and reduces combustion oscillation in each combustor.

[0007]

In order to solve the above-mentioned problems, the present invention provides a plurality of gas turbine combustors for combusting fuel and air to generate combustion gas, and a fuel manifold for supplying fuel to the combustor. In the fuel supply device for supplying the fuel gas, the fuel supply pipe connecting the plurality of gas turbine combustors from the fuel manifold is provided with a space portion having an arbitrary shape having a larger diameter than the fuel supply pipe.

According to the present invention, the pressure oscillation transmitted from each combustor to the fuel supply pipe is attenuated in pressure pulsation by the space portion provided in the fuel supply pipe, and the phase thereof is changed. This change depends on the shape of the space. Therefore, by appropriately selecting the shape of the space portion in each fuel supply pipe, it is possible to appropriately shift the phase of the pressure oscillation transmitted from each combustor and prevent resonance in the fuel manifold. Further, by damping the amplitude of the pressure vibration, it is possible to further suppress the influence of the pressure vibration transmitted from each combustor to the fuel manifold. As a result, fluctuations in the amount of fuel supplied from the fuel manifold to each combustor can be suppressed, and combustion oscillation in each combustor can be reduced.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a fuel supply device for a gas turbine combustor according to the present invention will be described with reference to FIGS. 1 to 5.

FIG. 1 is an explanatory diagram of a device of a fuel supply device for a gas turbine combustor in this embodiment. The fuel is sent from the main fuel supply pipe 10 to the annular fuel manifold 12 through the connecting point 11, and the branch fuel supply pipes 131, 132 arranged along the fuel manifold 12 at equal intervals.
133,134,135,136,137,138,1
It is sent via 39,140,141,142,143,144 to the combustor arranged annularly along the circumference of the gas turbine.

Fuel supply pipes 131, 132, 133, 13
4,135,136,137,138,139,140,
Conventionally, 141, 142, 143, and 144 are each configured by providing a cylindrical space portion 2 having a diameter larger than that of the fuel supply pipe with respect to equal diameter fuel supply pipes having the same shape. FIG. 2 shows the space parts 151, 152, 153, 15
4,155,156,157,158,159,16
0, 161, 162, 163, 164, and the fuel inlet 1 and outlet 3 in the space 2 have the same diameter. In addition, the space portion 2 may be configured as needed to correspond to the gas turbine by providing a plurality of space portions in one fuel supply pipe or providing none at all.

If the present invention is not practiced, the pressure transfer characteristics transmitted from each combustor to the fuel manifold 12 are substantially the same for reasons. Therefore, in the fuel manifold 12,
The pressure oscillation transmitted from each combustor causes resonance. This time,
The wavelength λ of the pressure oscillation of the frequency f [Hz] generated from each combustor is given by λ = Sv / f [m]. Here, Sv: sound velocity [m / s] in the fuel.

In this embodiment, the space portions 151, 152, 1
53, 154, 155, 156, 157, 158, 15
For 9, 160, 161, 162, 163 and 164, the length L [m] shown in FIG. 2 is shown in Table 1, and the length b [m] is the same.

[0014]

[Table 1]

FIG. 4 shows the pressure oscillation transmitted from each combustor to the fuel manifold 12 in this embodiment. According to this embodiment, it is possible to shift the phase of pressure vibration between the inlet 1 and the outlet 3 of the space 2 in FIG. 2 by (L / λ) * 360 °. Therefore, it is possible to prevent the pressure vibration transmitted from each combustor from resonating in the fuel manifold 12, and to suppress the fluctuation of the fuel supply amount to each combustor.

FIG. 5 shows the pressure amplitude attenuation rate with respect to the ratio of the inlet cross-sectional area of the space portion and the space cross-sectional area by the ratio of the pressure amplitude with and without the space portion. According to this embodiment, the vibration transmitted from each combustor is transmitted from the space inlet 1 to the space 2
As you enter, you can damp the amplitude of the vibration,
The influence of pressure oscillation from each combustor on the fuel manifold 12 can be reduced.

As another embodiment, the space 151,
152, 153, 154, 155, 156, 157, 1
58, 159, 160, 161, 162, 163, 16
When the shape shown in FIG. 3 is used for No. 4, the same effect can be obtained with a smaller volume as compared with the case of the shape shown in FIG. The lengths L1, L2, L of the spaces in FIG.
3 is L1 with respect to the length L when the shape of FIG. 2 is used.
It is an arbitrary L1, L2, L3 such that + L2 + L3 = L.

The present embodiment is applicable to all fuel supply systems for industrial gas turbine combustors having a plurality of combustors.

[0019]

According to the present invention, in the fuel supply device for a plurality of gas turbine combustors, it is possible to prevent the combustion vibration generated from each combustor from resonating, and suppress the vibration of the gas turbine combustor. it can.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a primary fuel supply device of a gas turbine combustor according to an embodiment of the present invention.

FIG. 2 is a sectional view of a space in a branch fuel supply pipe according to an embodiment of the present invention.

FIG. 3 is a sectional view of a space in a branch fuel supply pipe according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a pressure change transmitted from each branch pipe in the fuel manifold according to the embodiment of the present invention.

FIG. 5 is a characteristic diagram showing an amplitude attenuation rate of vibration according to a sectional area of a space according to an embodiment of the present invention.

[Explanation of symbols]

10 ... Main fuel supply pipe, 11 ... Connection point of main fuel supply pipe and annular fuel manifold, 12 ... Annular fuel manifold,
131-144 ... Branch fuel supply pipe, 151-164 ... Space.

Claims (1)

[Claims] 1. A fuel supply apparatus for supplying fuel from a fuel manifold to a plurality of gas turbine combustors for combusting fuel and air to generate combustion gas, the plurality of gas turbine combustors being provided from the fuel manifold. A fuel supply device for a gas turbine combustor, characterized in that the fuel supply pipe connected to the gas turbine combustor is provided with a space portion having a diameter larger than that of the fuel supply pipe.