Great research starts with great data.

Learn More
More >
Patent Analysis of

A Swirler for use in a burner of a gas turbine engine

Updated Time 15 March 2019

Patent Registration Data

Publication Number

GB2453114B

Application Number

GB2007018672

Application Date

25 September 2007

Publication Date

26 August 2009

Current Assignee

SIEMENS AKTIENGESELLSCHAFT

Original Assignee (Applicant)

SIEMENS AKTIENGESELLSCHAFT

International Classification

F23R3/14,F02C9/28

Cooperative Classification

F23C2900/07001,F23R3/14,F02C9/28

Inventor

NIGEL ANTHONY WILBRAHAM

Abstract

A swirler 2, for use in a burner of a gas turbine engine, has a series of vanes 9 arranged in a circle, and with flow slots 15 defined between adjacent vanes in the circle. The flow slots have inlet ends 12 and an outlet ends 14, and in use air flows along the slots from inlet to outlet ends and liquid fuel is supplied from at least one fuel injection port 10, such that a swirling mix of air and fuel is provided at the outlet ends of the flow slots. At least one flow slot also has a bleed hole 51 and an associated control unit 4, whereby air/fuel can be bled from the slot in dependence on the load on the gas turbine engine. The control unit may be arranged to open the bleed hole during part-load operation, and close the bleed hole as full load operation is approached. Each flow slot may also have additional bleed holes (63, 65 fig 5), and the fuel injection port may be located adjacent the outlet end of the at least one flow slot. The invention assists in achieving a more uniform distribution of fuel droplets, such as at part-load engine conditions.

Read more

Claims

-10 -Claims: 1. A swirler for use in a burner of a gas turbine engine, the swirler comprising a series of vanes arranged in a circle, flow slots being defined between adjacent vanes in the circle, each flow slot having an inlet end and an outlet end, in use of the swirler air flowing along each flow slot from its inlet to its outlet ends and fuel being supplied to the flow slots such that the swirler provides a swirling mix of air and fuel at the outlet ends of the flow slots, at least one flow slot including in a side thereof an injection port whereby liquid fuel can be injected into the flow slot, the at least one flow slot also including a bleed hole whereby air/fuel can be bled from the flow slot, wherein the swirler includes a control unit arranged to control the bleeding of air/fuel via the bleed hole in dependence on the load on the gas turbine engine.

2. A swirler according to claim 1 wherein the control unit is arranged to open the bleed hole during part load operation of the gas turbine engine, and close the bleed hole as full load operation is approached.

3. A swirler according to claim 1 or claim 2 wherein the bleed hole is located in a side of the at least one flow slot that terminates at the inlet end of the flow slot in an edge about which air turns to enter the flow slot.

4. A swirler according to claim 3 wherein the bleed hole is located adjacent the edge.

5. A swirler according to any one of the preceding claims wherein each flow slot has a bottom side, a top side, and -11 -first and second further sides, all sides extending along the slot from its inlet to its outlet ends, the bottom and top sides also extending between the two adjacent vanes defining the slot, the first and second further sides extending between the top and bottom sides, the first further side comprising a side of one of the two adjacent vanes, the second further side comprising a side of the other of the two adjacent vanes, wherein the injection port is located in the bottom side of the at least one flow slot, and the bleed hole is located in the top side of the at least one flow slot.

6. A swirler according to claim 5 wherein the injection port is located adjacent the outlet end of the at least one flow slot.

7. A swirler according to claim 5 or claim 6 further comprising first and second further bleed holes, the first further bleed hole being located in the first further side of the at least one flow slot, the second further bleed hole being located in the second further side of the at least one flow slot, wherein the first and second further sides of the at least one flow slot terminate at its inlet end in edges about which air turns to enter the flow slot.

8. A swirler according to claim 7 wherein the first further bleed hole is located adjacent the edge of the first further side, and the second further bleed hole is located adjacent the edge of the second further side.

9. A swirler according to any one of the preceding claims wherein each vane is wedge shaped, and the wedge shaped vanes are arranged in the circle such that the thin ends of the -12 -wedge shaped vanes are directed generally radially inwardly, the opposite broad ends of the wedge shaped vanes face generally radially outwardly, and the flow slots defined between adjacent vanes are directed generally radially inwardly.

Read more

Claim Tree

  • 1
    1. A swirler for use in a burner of a gas turbine engine, the swirler comprising
    • a series of vanes arranged in a circle, flow slots being defined between adjacent vanes in the circle, each flow slot having an inlet end and an outlet end, in use of the swirler air flowing along each flow slot from its inlet to its outlet ends and fuel being supplied to the flow slots such that the swirler provides a swirling mix of air and fuel at the outlet ends of the flow slots, at least one flow slot including in a side thereof an injection port whereby liquid fuel can be injected into the flow slot, the at least one flow slot also including a bleed hole whereby air/fuel can be bled from the flow slot, wherein the swirler includes a control unit arranged to control the bleeding of air/fuel via the bleed hole in dependence on the load on the gas turbine engine.
    • 2. A swirler according to claim 1 wherein
      • the control unit is arranged to open the bleed hole during part load operation of the gas turbine engine, and close the bleed hole as full load operation is approached.
    • 3. A swirler according to claim 1 or claim 2 wherein
      • the bleed hole is located in a side of the at least one flow slot that terminates at the inlet end of the flow slot in an edge about which air turns to enter the flow slot.
    • 5. A swirler according to any one of the preceding claims wherein
      • each flow slot has a bottom side, a top side, and -11 -first and second further sides, all sides extending along the slot from its inlet to its outlet ends, the bottom and top sides also extending between the two adjacent vanes defining the slot, the first and second further sides extending between the top and bottom sides, the first further side comprising
    • 9. A swirler according to any one of the preceding claims wherein
      • each vane is wedge shaped, and the wedge shaped vanes are arranged in the circle such that the thin ends of the -12 -wedge shaped vanes are directed generally radially inwardly, the opposite broad ends of the wedge shaped vanes face generally radially outwardly, and the flow slots defined between adjacent vanes are directed generally radially inwardly.
See all 1 independent claims

Description

-1-2453114 A swirler for use in a burner of a gas turbine engine The present invention relates to a swirler for use in a burner of a gas turbine engine.

More particularly the present invention relates to such a swirler comprising a series of vanes arranged in a circle, flow slots being defined between adjacent vanes in the circle, each flow slot having an inlet end and an outlet end, in use of the swirler air flowing along each flow slot from its inlet to its outlet ends and fuel being supplied to the flow slots such that the swirler provides a swirling mix of air and fuel at the outlet ends of the flow slots, at least one flow slot including in a side thereof an injection port whereby liquid fuel can be injected into the flow slot, the at least one flow slot also including a bleed hole whereby air/fuel can be bled from the flow slot.

It is desired to improve the mixing of air and fuel that takes place in the flow slots thereby to improve the mix of air and fuel in the swirling mix provided by the swirler.

According to the present invention there is provided a swirler for use in a burner of a gas turbine engine, the swirler comprising a series of vanes arranged in a circle, flow slots being defined between adjacent vanes in the circle, each flow slot having an inlet end and an outlet end, in use of the swirler air flowing along each flow slot from its inlet to its outlet ends and fuel being supplied to the flow slots such that the swirler provides a swirling mix of air and fuel at the outlet ends of the flow slots, at least one flow slot including in a side thereof an injection port whereby liquid fuel can be injected into the flow slot, the at least one flow slot also including a bleed hole whereby air/fuel can be bled from the flow slot, wherein the swirler includes a control unit arranged to control the bleeding of air/fuel via the bleed hole in dependence on the load on the gas turbine engine.

In a swirler according to the preceding paragraph, it is preferable that the control unit is arranged to open the bleed hole during part load operation of the gas turbine engine, and close the bleed hole as full load operation is approached.

In a swirler according to either of the preceding two paragraphs, it is preferable that the bleed hole is located in a side of the at least one flow slot that terminates at the inlet end of the flow slot in an edge about which air turns to enter the flow slot.

In a swirler according to the preceding paragraph, it is preferable that the bleed hole is located adjacent the edge.

In a swirler according to any one of the preceding four paragraphs, it is preferable that each flow slot has a bottom side, a top side, and first and second further sides, all sides extending along the slot from its inlet to its outlet ends, the bottom and top sides also extending between the two adjacent vanes defining the slot, the first and second further sides extending between the top and bottom sides, the first further side comprising a side of one of the two adjacent vanes, the second further side comprising a side of the other of the two adjacent vanes, wherein the injection port is located in the bottom side of the at least one flow slot, and the bleed hole is located in the top side of the at least one flow slot.

In a swirler according to the preceding paragraph, it is preferable that the injection port is located adjacent the outlet end of the at least one flow slot.

In a swirler according to either of the preceding two paragraphs, it is preferable that the swirler further comprises first and second further bleed holes, the first further bleed hole being located in the first further side of the at least one flow slot, the second further bleed hole being located in the second further side of the at least one flow slot, wherein the first and second further sides of the at least one flow slot terminate at its inlet end in edges about which air turns to enter the flow slot.

In a swirler according to the preceding paragraph, it is preferable that the first further bleed hole is located adjacent the edge of the first further side, and the second further bleed hole is located adjacent the edge of the second further side.

In a swirler according to any one of the eight preceding paragraphs, it is preferable that each vane is wedge shaped, and the wedge shaped vanes are arranged in the circle such that the thin ends of the wedge shaped vanes are directed generally radially inwardly, the opposite broad ends of the wedge shaped vanes face generally radially outwardly, and the flow slots defined between adjacent vanes are directed generally radially inwardly.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig 1 is a schematic section through a burner for a gas turbine engine, which burner includes a swirler in accordance with the present invention; Fig 2 is a perspective view of the swirler of Fig 1; Fig 3 shows a pair of adjacent wedge shaped vanes of the swirler of Fig 1; Fig 4 illustrates operation of the swirler of Fig 1; and Fig 5 illustrates a modification to the swirler of Fig 1.

Referring to Fig 1, the burner comprises an outer casing 1, a swirler 3, a pre-chamber 5, and a combustion chamber 7.

Swirler 3 comprises a radial swirler 2 and associated control unit 4.

Referring also to Fig 2, radial swirler 2 comprises a series of wedge shaped vanes 9 arranged in a circle. The thin ends 11 of the wedge shaped vanes are directed generally radially inwardly. The opposite broad ends 13 of the wedge shaped vanes face generally radially outwardly. Generally radially inwardly directed straight flow slots 15 are defined between adjacent wedge shaped vanes 9 in the circle. Each flow slot has a bottom side 42 and a top side 44 spaced apart in a direction perpendicular to the plane of the circle in which the wedge shaped vanes 9 are arranged. Each flow slot also has first and second sides 46, 48 defined by sides of the adjacent wedge shaped vanes 9 between which the slot is formed. Each flow slot further has a radially outer inlet end 12 and a radially inner outlet end 14.

Compressed air travels in the direction of arrows 17 in Fig 1 between outer casing 1 and combustion chamber 7/pre-chamber 5. As indicated by arrows 16, the air then turns through 90 degrees so as to enter the flow slots 15 at their inlet ends 12. The air then travels generally radially inwardly along flow slots 15 to their outlet ends 14. Liquid fuel is supplied to flow slots 15 by way of injection ports 10 in the bottom sides 42 of the slots adjacent the outlet ends 14 of the slots. Further, gaseous fuel is supplied to flow slots 15 by way of injection ports 18 in the sides 48 of the wedge shaped vanes 9. The air/fuel mix enters the central space 21 within the circle of wedge shaped vanes 9 generally in the direction as indicated by arrows 23, thereby to form a swirling air/fuel mix 25 in central space 21. As indicated by arrows 27, the swirling air/fuel mix 25 travels along pre-chamber 5 to combustion chamber 7 where it combusts.

Fig 3 shows a single flow slot 15 between a pair of adjacent wedge shaped vanes 9. Fig 3 shows more clearly the slot's bottom side 42, top side 44, first side 46, second side 48, inlet end 12, and outlet end 14. Liquid fuel injection port 10 is located in the bottom side 42 of the slot adjacent the outlet end 14 of the slot. A bleed hole 51 is located in the opposite top side 44 of the slot adjacent the inlet end 12 of the slot.

The purpose of bleed hole 51 will now be explained. Figs 4(1) to 4(iv) are schematic sections of the slot of Fig 3, each section being taken in a plane parallel to the first and second sides 46, 48 of the slot, the plane being midway between the sides 46, 48. In Figs 4(i) and 4(u) the bleed hole 51 is removed. This is to show operation without the bleed hole.

Fig 4(i) shows the distribution of liquid fuel droplets emanating from injection port 10 when the gas turbine engine is operating at full load. It can be seen that the liquid fuel spray 53 extends over most of the height 55 of the flow slot. This is desirable as it leads to more thorough mixing of the liquid fuel 53 with the air 57 travelling along the slot.

Fig 4(u) shows the distribution of liquid fuel droplets emanating from injection port 10 when the gas turbine engine is operating at part load. It can be seen that the liquid fuel spray 53 only extends over an uppermost portion of the height 55 of the flow slot. This is not desirable as it results in less thorough mixing of the liquid fuel 53 with the air 57 travelling along the slot.

The reason for the behaviour of the fuel spray as shown in Fig 4(u) is threefold. Firstly, at part load, there is less pressure in the fuel supply to injection port 10, resulting in larger liquid fuel droplets emanating from port 10. These larger droplets have higher momentum and hence travel further up the flow slot, resulting in a concentration of droplets at the top of the slot. Secondly, at part load, the speed of the air flow 57 along the slot is often less (due to bleeding off of air upstream of the swirler), resulting in greater penetration of the slot by the droplets emanating from injection port 10. Thirdly, turbulent flow present at the top of the slot tends to trap fuel in this region. Thus, fuel droplets that have reached the top of the slot have difficulty escaping to lower regions of the slot. It is to be noted that there is turbulent flow present at the top of each flow slot 15 due to action of the edge at the top of the slot at its inlet end 12. This edge is referenced 59 in Fig 4, and acts as a trip to the air flow 16 as it turns through 90 degrees as it travels around the edge. Reference is also to be made to Fig 1 and the arrows 16 for this turning of the air through 90 degrees.

The flow slot of Fig 4(iii) includes the bleed hole 51. Fig 4(iii) shows the distribution of liquid fuel droplets emanating from injection port 10 when the gas turbine engine is operating at full load. When the engine is operating at full load, the control unit 4 (see Fig 1) associated with the radial swirler 2 closes bleed hole 51. Thus, the distribution of liquid fuel droplets in the slot is the same as if there was no bleed hole present, i.e. is the same as shown in Fig 4 (i) This is desirable because, as in Fig 4 (i), the liquid fuel spray 53 extends over most of the height 55 of the flow slot.

The flow slot of Fig 4(iv) also includes the bleed hole 51.

Fig 4(iv) shows the distribution of liquid fuel droplets emanating from injection port 10 when the gas turbine engine is operating at part load. When the engine is operating at part load, the control unit 4 opens bleed hole 51. This has the effect of bleeding away the turbulent flow normally present at the top of the flow slot, with the result that fuel droplets reaching the top of the slot no longer tend to be trapped there by the turbulent flow. This assists in achieving a more uniform distribution of the droplets. As shown in Fig 4(iv), opening bleed hole 51 at part load operation achieves a liquid fuel spray 53 that extends over most of the height 55 of the flow slot. This is comparable to the extent of fuel spray achieved at full load operation.

Referring to Fig 5, edges 61, 63 also present at the inlet end 12 of each flow slot, also act as trips to the air flow 16 as it turns through 90 degrees as it travels around the edges 61, 63. This produces turbulent flow regions over the faces of the first and second sides 46, 48 of the flow slot.

Again, these turbulent flow regions tend to trap fuel droplets hindering their uniform distribution. Accordingly, the flow slot of Fig 5 is provided with a further two bleed holes 65, 67 in sides 46, 48 adjacent edges 61, 63. As with bleed hole 51, bleed holes 65, 67 are opened at part load operation of the gas turbine engine to bleed away the turbulent regions over the first and second sides 46, 48.

In the above described swirler, bleed hole 51 is located adjacent edge 59 in side 44. It is to be understood that bleed hole 51 could be located adjacent edge 59 in the other side of edge 59, i.e. the side of edge 59 that forms the 90 degrees turn with side 44. The same desired effect of bleeding away the turbulent region over side 44 would be achieved. The same applies to bleed holes 65, 67 located adjacent edges 61, 63 in sides 46, 48.

In the above described swirler, all flow slots 15 are provided with a liquid fuel injection port 10. This need not be the case -only selected flow slots may be provided with a liquid fuel injection port. For best operation, one or more bleed holes, as 51, 65, 67, are provided in respect of all flow slots that have a liquid fuel injection port. However, the present invention extends to where not all flow slots that have a liquid fuel injection port also have a bleed hole.

The above description relates to a radial swirler. It is to be appreciated that the present invention also extends to axial swirlers. Axial swirlers also comprise a series of vanes arranged in a circle, flow slots being defined between adjacent vanes in the circle, each flow slot having an inlet end and an outlet end, in use of the swirler air flowing along each flow slot from its inlet to its outlet ends and fuel being supplied to the flow slots such that the swirler provides a swirling mix of air arid fuel at the outlet ends of the flow slots. Use of the present invention in an axial swirler would require a flow slot to include in a side thereof an injection port whereby liquid fuel can be injected into the flow slot, that the flow slot also include a bleed hole whereby air/fuel can be bled from the flow slot, and that the swirler include a control unit arranged to control the bleeding of air/fuel via the bleed hole in dependence on the load on the gas turbine engine.

Read more
PatSnap Solutions

Great research starts with great data.

Use the most comprehensive innovation intelligence platform to maximise ROI on research.

Learn More

Citation

Title Current Assignee Application Date Publication Date
Staged gas turbine combustion chamber with counter swirling arrays of radial vanes having interjacent fuel injection ROLLS-ROYCE PLC 13 April 1993 14 June 1994
Dry low emission combustor for gas turbine engines ROLLS-ROYCE CORPORATION 28 March 1997 18 August 1998
Swirler assembly GENERAL ELECTRIC COMPANY 07 December 2006 28 January 2009
Swirler assembly GENERAL ELECTRIC COMPANY 07 December 2006 13 June 2007
Title Current Assignee Application Date Publication Date
TURBINE ENGINE CONTROL SYSTEM SIEMENS AKTIENGESELLSCHAFT 27 June 2014 30 January 2019
See full citation

PatSnap Solutions

PatSnap solutions are used by R&D teams, legal and IP professionals, those in business intelligence and strategic planning roles and by research staff at academic institutions globally.

PatSnap Solutions
Search & Analyze
The widest range of IP search tools makes getting the right answers—and asking the right questions—easier than ever. One click analysis extracts meaningful information on competitors and technology trends from IP data.
Business Intelligence
Gain powerful insights into future technology changes, market shifts and competitor strategies.
Workflow
Manage IP-related processes across multiple teams and departments with integrated collaboration and workflow tools.
Contact Sales