Pressure atomizer nozzle

• US 5,934,555 A
• Filed: 03/04/1997
• Issued: 08/10/1999
• Est. Priority Date: 03/05/1996
• Status: Expired due to Term

• Current Assignee: Ansaldo Energia Switzerland AG (Ansaldo Energia SPA)
• Original Assignee: ABB Research Ltd. (ABB Limited)
• Inventors: Jansohn, Peter, Steinbach, Christian, Knopfel, Hans Peter, Dobbeling, Klaus
• Primary Examiner(s): Kashnikow, Andres
• Assistant Examiner(s): Ganey, Steven J.
• Application Number:
  US08/811,006
• Time in Patent Office: 889 Days
• Field of Search: 239/590, 239/590.3, 239/399, 239/403, 239/404, 239/405, 239/406, 239/461, 239/463, 239/466, 239/8, 239/423, 239/424, 239/11, 239/426, 239/491, 239/1, 239/493, 239/600
• US Class Current: 239/11
• CPC Class Codes: B05B 1/3442 the interface being a cone having the same axis as the outlet
• CPC Class Codes: B05B 1/3447 the interface being a cylinder having the same axis as the outlet
• CPC Class Codes: B05B 1/3478 the liquid flowing at least two different courses before reaching the swirl chamber
• CPC Class Codes: B05B 7/0408 with arrangements for mixing two or more liquids
• CPC Class Codes: B05B 7/10 producing a swirling discharge
• CPC Class Codes: F23C 2900/07002 Premix burners with air inlet slots obtained between offset curved wall surfaces, e.g. double cone burners
• CPC Class Codes: F23C 7/002 the air being submitted to a rotary or spinning motion cyclonic combustion chamber F23C3/006
• CPC Class Codes: F23D 11/26 with provision for varying the rate at which the fuel is sprayed
• CPC Class Codes: F23D 11/383 with swirl means

Abstract

A pressure atomizer nozzle comprises a nozzle body (30) in which is formed a turbulence and/or swirl chamber (39) and having a nozzle bore (33). At least one first feed channel (41, 41a) for the liquid (37) to be atomized connects to the chamber as a first feed stage for feeding said liquid (37) under pressure. At least one second feed channel (38) connects to the chamber as a second feed stage for feeding part of the liquid (37) to be atomized or for feeding a second liquid (37'"'"') to be atomized. The second feed channel feeds liquid into the chamber under pressure and with a swirl. The two stage pressure atomizer nozzle allows, for example, simple adaptation of the fuel spray cone angle to the respective operating conditions of a gas turbine burner.

Claims

1. A method for operating a pressure atomizer nozzle having a nozzle body enclosing a chamber for at least one of fluid tubulence and swirl, the body having a nozzle bore connecting the chamber to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl, the method comprising the steps of:

in full-load and overload operation, introducing all of a liquid to be atomized through the at least one first feed channel for a swirl-free turbulence flow to the turbulence chamber, so that a highly turbulent flow being produced in the chamber passes into the outer space through the nozzle bore, and

in part-load and low-load operation, feeding a first portion of the liquid to be atomized through the at least one first feed channel for turbulent flow into the chamber and a remaining portion through the at least one further feed channel for a flow with a high degree of swirl into the chamber, a total flow produced in the chamber passes into the, wherein a proportion of liquid fed in by the at least one further feed channel being increased as a total mass flow of liquid decreases.

2. The method as claimed in claim 1 wherein in changing between full load and part load operation, the method includes continuing feeding through the at least one first feed channel for a smooth switchover between load stages.

3. The method as claimed in claim 1 comprising the steps of feeding liquid through both the at least one first feed channel and the at least one further feed channel simultaneously and varying a throughput to each feed channel for controlling a load.

4. The method as claimed in claim 1, comprising the step of feeding liquid to one of the at least one first feed channel and at least one further feed channel.

5. The method for operating a pressure atomizer nozzle including a nozzle body enclosing a chamber for at least one of fluid turbulence and swirl, the body having a nozzle bore connecting the chamber to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure with a swirl, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure with a swirl greater than the swirl from the at least one first feed channel, the method comprising the steps of:

in full-load and overload operation, feeding all of a liquid to be atomized into the chamber through the at least one feed channel, a swirling flow being produced there which then passes into the outer space through the nozzle bore,

in part-load and low-load operation, feeding a first portion of the liquid to be atomized into the chamber through the at least one feed channel, and feeding a remaining second portion of the liquid into the chamber through the at least one further feed channel, wherein the first and second portions combine in the chamber producing there a flow with a high degree of swirl which then passes into the outer space through the nozzle bore, wherein a proportion of liquid fed in through the further swirl stage is increased as a total mass flow of liquid decreases.

6. The method as claimed in claim 5 wherein in changing between full load and part load operation, the method includes continuing feeding through the at least one first feed channel for a smooth switchover between load stages.

7. The method as claimed in claim 5 comprising the steps of feeding liquid through both the at least one first feed channel, and the at least one further feed channel simultaneously and varying a throughput to each feed channel for controlling a load.

8. The method as claimed in claim 5, comprising the step of feeding liquid to one of the at least one first feed channel and at least one further feed channel.

9. A method for burning liquid fuel in a burner without a premixing section, the burner having an interior space and a nozzle spraying a conical column of liquid fuel which spreads out in a direction of flow in the interior of the burner by atomization of the fuel, wherein the atomized fuel does not wet the walls of the interior and wherein a combustion airstream flows tangentially into the interior space to surround the fuel spray, ignition of the mixture taking place at an outlet of the burner and a flame being stabilized in a region of the burner mouth by a reverse-flow zone, wherein the nozzle is a pressure atomizer nozzle comprising a nozzle body enclosing a chamber for at least one of fluid tubulence and swirl, the body having a nozzle bore connecting the chamber to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl, the method comprising the steps of

in full-load and overload operation, introducing all of a liquid to be atomized through the at least one first feed channel for a swirl-free turbulence flow to the turbulence chamber, so that a highly turbulent flow being produced in the chamber passes into the outer space through the nozzle bore, and

in part-load and low-load operation, feeding a first portion of the liquid to be atomized through the at least one first feed channel for turbulent flow into the chamber and a remaining portion through the at least one further feed channel for a flow with a high degree of swirl into the chamber, a total flow produced in the chamber passes into the outer space through the nozzle bore, wherein a proportion of liquid fed in by the at least one further feed channel being increased as a total mass flow of liquid decreases,

and wherein 3 to 7% of the combustion airstream is guided around the nozzle as an enveloping airstream.

10. A method for burning liquid fuel in a burner with a premixing section, the burner having an interior space and a nozzle injecting a conical column of liquid fuel which spreads out in a direction of flow in the interior space by atomization of the fuel and does not wet walls of the interior and wherein a combustion airstream flows tangentially into the burner space to surround the fuel spray, a swirling flow thereby being produced which, downstream of the burner interior, passes into a mixing section extending in the direction of flow, and wherein ignition of the mixture takes place only at an outlet of the burner, the flame being stabilized in a region of the burner mouth by a reverse-flow zone, wherein the nozzle is a pressure atomizer nozzle, having a nozzle body enclosing a chamber for at least one of fluid turbulence and swirl, the body having a nozzle bore connecting the chamber to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl, the method comprising the steps of:

in full-load and overload operation, introducing all of a liquid to be atomized through the at least one first feed channel for a swirl-free turbulence flow to the turbulence chamber, so that a highly turbulent flow being produced in the chamber passes into the outer space through the nozzle bore, and

in part-load and low-load operation, feeding a first portion of the liquid to be atomized through the at least one first feed channel for turbulent flow into the chamber and a remaining portion through the at least one further feed channel for a flow with a high degree of swirl into the chamber, a total flow produced in the chamber passes into the outer space through the nozzle bore, wherein a proportion of liquid fed in by the at least one further feed channel being increased as a total mass flow of liquid decreases, and wherein 3 to 7% of the combustion airstream is guided around the nozzle as an enveloping airstream.

11. A pressure atomizer nozzle comprising a nozzle body enclosing a chamber for at least one of turbulence and swirl, the body having a nozzle bore connected to the chamber and having a smaller diameter than a diameter of the chamber to produce a spray to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure and without swirl, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl in the chamber, wherein the nozzle bore is arranged in a cap of the nozzle body, and wherein the nozzle body includes a first tube and the second tube having smaller outside diameter than the first tube and inserted in the first tube, the second tube enclosing the chamber, the second tube extending to the cap, and wherein said at least one further feed channel comprises a slot provided in a cap end of the second tube, said slot being arranged tangentially relative to the chamber for forming a swirl channel, the slot connecting an annular space between the first tube and the second tube to the chamber, and further comprising a filler piece mounted in the second tube spaced from the cap to define the chamber therebetween, and wherein the at least one first feed channel is arranged parallel to nozzle body axis in the filler piece.

12. A pressure atomizer nozzle comprising a nozzle body enclosing a chamber for at least one of turbulence and swirl, the body having a nozzle bore connected to the chamber and having a smaller diameter than a diameter of the chamber to produce a spray to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure and without swirl, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl in the chamber, wherein the nozzle bore is arranged in a cap of the nozzle body, and wherein the nozzle body includes a first tube and a second tube having a smaller outside diameter than the first tube and being inserted in the first tube, the second tube enclosing the chamber and extending to the cap, and wherein said at least one further feed channel comprises a slot provided in a cap end of the second tube, said slot being arranged tangentially relative to the chamber for forming a swirl channel, the slot connecting an annular space between the first tube and the second tube to the chamber, and further comprising a filler piece mounted in the second tube spaced from the cap, the chamber being enclosed therebetween, and wherein the first feed channel is arranged as an annular gap between the filler piece and inner walls of the second tube.

13. A pressure atomizer nozzle comprising a nozzle body enclosing a chamber for at least one of turbulence and swirl, the body having a nozzle bore connected to the chamber and having a smaller diameter than a diameter of the chamber to produce a spray to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl in the chamber, wherein the nozzle bore is arranged in a cap of the nozzle body, and wherein the nozzle body includes a first tube and a second tube having a smaller outside diameter than the first tube and being inserted in the first tube, and annular channel formed between the tubes proving a feed line for a swirl stage, and further comprising a filler piece mounted in the second tube spaced from the cap to define the chamber, wherein the at least one further channel comprises at least one tangentially arranged swirl channel arranged in the and second tube connecting the annular channel to the chamber, and wherein the at least one feed channel is arranged in the filler piece parallel to a nozzle body axis, as a turbulence channel for the liquid to be atomized.

14. A pressure atomizer nozzle comprising a nozzle body enclosing a chamber for at least one of turbulence and swirl, the body having a nozzle bore connected to the chamber and having a smaller diameter than a diameter of the chamber to produce a spray to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl in the chamber, wherein the nozzle bore is arranged in a cap of the nozzle body, and wherein the nozzle body includes a first tube and a second tube having a smaller outside diameter than the first tube and being inserted in the first tube, an annular channel formed between the tubes providing a feed line for a swirl stage and further comprising a filler piece mounted in the second tube and defining the chamber with the cap, wherein the at least one further feed channel is a tangentially directed swirl channel arranged in the second tube for connecting the annular channel to the chamber, and the at least one feed channel is arranged parallel to nozzle body axis in the filler piece to act as a turbulence channel for the liquid to be atomized.

15. A pressure atomizer nozzle comprising a nozzle body enclosing a chamber for at least one of turbulence and swirl, the body having a nozzle bore connected to the chamber and having a smaller diameter than a diameter of the chamber to produce a spray to an outer space and having at least one first feed channel for feeding a liquid to be atomized into the chamber under pressure and with swirl, the body having at least one further feed channel for feeding one of a portion of the liquid to be atomized or a second liquid to be atomized into the chamber under pressure, the at least one further feed channel being formed to generate a swirl in the chamber, wherein the nozzle bore is arranged in a cap of the nozzle body, the nozzle body including a first tube and a second tube having a smaller outside diameter than the first tube and inserted in the first tube, the second tube enclosing the chamber, the second tube extending to the cap, and the at least one further feed channel comprising at least one slot provided in a cap end of the second tube, said slot being arranged tangentially to form a swirl channel connecting annular space between the first tube and the second tube to the chamber and further comprising a filler piece mounted in the second tube spaced from the cap to define therebetween the chamber, and wherein the at least one first feed channel is formed tangentially as at least one swirl channel in the filler piece.

16. The pressure atomizer nozzle as claimed in claim 15 wherein the at least one first feed channel is formed to produce a greater swirl than the at least one further feed channel.