Method for operating a combustion device including injecting a fluid together with diluent fuel to address combustion pulsations

1. Method for operating a combustion device comprising:

supplying a fuel and an oxidizer into the combustion device and burning them;

supplying, during at least a part of a transient operation, an additional fluid together with the fuel, the transient operation including one of a start-up of the combustion device, a switch-off of the combustion device or a fuel switch-over of the combustion device; and

regulating the amount of the additional fluid to counteract combustion pulsations, wherein the additional fluid is an inert fluid, and the additional fluid is at least partly mixed with the fuel prior to injection.

2. The method according to claim 1 , comprising choosing a first parameter indicative of a fuel feed and supplying the additional fluid only when the fuel feed reaches a predetermined value of the first parameter.

3. The method according to claim 2 , wherein the first parameter is the fuel mass flow (M).

4. The method according to claim 3 , comprising:

supplying the additional fluid only when the fuel mass flow is below a critical value at which pulsations start to generate.

5. The method according to claim 2 , wherein the first parameter is a differential pressure (ΔP) between a fuel supply and the inside of the combustion device.

6. The method according to claim 2 , comprising choosing a second parameter indicative of the fuel and additional fluid feed, the regulating including maintaining the second parameter above or below a second predetermined value or maintaining the second parameter within a prefixed range (R).

7. The method according to claim 6 , wherein the second parameter range (R) corresponds to the second predetermined value of the second parameter ±10% or to the second predetermined value of the second parameter ±1% or to the second predetermined value of the second parameter.

8. The method according to claim 6 , wherein a bottom or a top of the range (R) correspond to the second predetermined value (SPc) of the second parameter (SP).

9. The method according to claim 6 , wherein the second parameter is the fuel and additional fluid mass flow (M).

10. The method according to claim 6 , wherein the second parameter is the differential pressure (ΔP) between a fuel and additional fluid supply and the inside of the combustion device.

11. The method according to claim 2 , wherein the predetermined value is a value at which pulsations start to generate.

12. The method according to claim 1 , wherein the fuel is supplied into the combustion device via a fuel supply, wherein the additional fluid is supplied into this fuel supply.

13. The method according to claim 1 , wherein the fuel is a liquid fuel and the additional fluid is also liquid.

14. The method according to claim 1 , wherein the fuel is a gaseous fuel and the additional fluid is also gaseous.

15. The method according to claim 1 , comprising:

supplying the additional fluid together with the fuel to create a combined flow of fluid and fuel, and the combined flow is then mixed with an oxidiser during at least a part of the transient operation.

16. The method according to claim 1 , comprising:

counteracting the combustion pulsations by minimising the formation of combustion pulsations.

17. Method for operating a combustion device comprising:

supplying a fuel and an oxidizer into the combustion device and burning them;

supplying, during at least a part of a transient operation, an additional fluid together with the fuel;

regulating the amount of the additional fluid to counteract combustion pulsations; and

choosing a first parameter indicative of a fuel feed and supplying the additional fluid only when the fuel feed reaches a predetermined value of the first parameter, wherein the first parameter is a differential pressure (ΔP) between a fuel supply and the inside of the combustion device.

18. Method for operating a combustion device comprising:

supplying a fuel and an oxidizer into the combustion device and burning them;

supplying, during at least a part of a transient operation, an additional fluid together with the fuel;

regulating the amount of the additional fluid to counteract combustion pulsations;

choosing a first parameter indicative of a fuel feed and supplying the additional fluid only when the fuel feed reaches a predetermined value of the first parameter;

choosing a second parameter indicative of the fuel and additional fluid feed, the regulating including maintaining the second parameter above or below a second predetermined value or maintaining the second parameter within a prefixed range (R); and

wherein the second parameter prefixed range (R) corresponds to the second predetermined value of the second parameter ±10% or to the second predetermined value of the second parameter ±1% or to the second predetermined value of the second parameter.