Combustion chamber with separate, valved air mixing passages for separate combustion zones

A combustion chamber assembly comprising a combustion chamber having a primary combustion zone, a secondary combustion zone, at least one primary fuel and air mixing duct, primary fuel injector means to supply fuel into the primary fuel and air mixing duct, first valve means to control the supply of air to the at least one primary fuel and air mixing duct, the primary fuel and air mixing duct being arranged to supply fuel and air into the primary combustion zone, at least one secondary fuel and air mixing duct, secondary fuel injector means to supply fuel to the secondary fuel and air mixing duct, second valve means to control the supply of air to the secondary fuel and air mixing duct, the secondary fuel and air mixing duct being arranged to supply fuel and air into the secondary combustion zone, means to supply cooling air and dilution air to the combustion chamber, means to measure the flow of air to the primary and secondary fuel and air mixing ducts, and means to control the supply of fuel to the primary and secondary fuel injector means in response to the measured flows of air to the primary and secondary fuel and air mixing ducts to minimize emissions from the combustion chamber, said combustion chamber having a tertiary combustion zone, at least one tertiary fuel and air mixing duct, tertiary fuel injector means to supply fuel to the tertiary fuel and air mixing duct, means to supply air to the tertiary fuel and air mixing duct, the tertiary fuel and air mixing duct being arranged to supply fuel and air into the tertiary combustion zone, means to measure the flow of air to the tertiary fuel and air mixing duct and means to control the supply of fuel to the primary, secondary and tertiary fuel injector means in response to the measured flows of air to the primary, secondary and tertiary fuel and air mixing ducts to minimize emissions from the combustion chamber, each tertiary fuel and air mixing duct comprising a pair of axial flow swirlers arranged coaxially to swirl the air in opposite directions, tertiary fuel injector means to supply fuel coaxially of the axial flow swirlers in the tertiary fuel and air mixing duct, said tertiary fuel and air mixing duct being arranged to inject fuel and air into the combustion chamber with a tangential component opposite to the secondary fuel and air mixing duct and a downstream flow component.

A method of operating a combustion chamber assembly comprising a combustion chamber having a primary combustion zone, a secondary combustion zone and a tertiary combustion zone, at least one primary fuel and air mixing duct, primary fuel injector means to supply fuel to the primary fuel and air mixing duct, first valve means to control the supply of air to the at least one primary fuel and air mixing duct, the primary fuel and air mixing duct being arranged to supply fuel and air into the primary combustion zone, at least one secondary fuel and air mixing duct, secondary fuel injector means to supply fuel to the secondary fuel and air mixing duct, second valve means to control the supply of air to the secondary fuel and air mixing duct, the secondary fuel and air mixing duct being arranged to supply fuel and air into the secondary combustion zone, the method comprising closing the first valve means and second valve means in a first mode of operation, opening the first valve means and maintaining the second valve means closed in a second mode of operation and opening the first valve means and the second valve means in a third mode of operation, at least one tertiary fuel and air mixing duct, tertiary fuel injector means to supply fuel to the tertiary fuel and air mixing duct, means to supply air to the tertiary fuel and air mixing duct, the tertiary fuel and air mixing duct being arranged to supply fuel and air into the tertiary combustion zone.

A method of operating a combustion chamber assembly comprising a combustion chamber having a primary combustion zone, a secondary combustion zone and a tertiary combustion zone, at least one primary fuel and air mixing duct, primary fuel injector means to supply fuel to the primary fuel and air mixing duct, first valve means to control the supply of air to the at least one primary fuel and air mixing duct, the primary fuel and air mixing duct being arranged to supply fuel and air into the primary combustion zone, at least one secondary fuel and air mixing duct, secondary fuel injector means to supply fuel to the secondary fuel and air mixing duct, second valve means to control the supply of air to the secondary fuel and air mixing duct, the secondary fuel and air mixing duct being arranged to supply fuel and air into the secondary combustion zone, a tertiary fuel and air mixing duct and the method comprising closing the first valve means and second valve means in a first mode of operation, opening the first valve means and maintaining the second valve means closed in a second mode of operation and opening the first valve means and the second valve means in a third mode of operation, supplying about 5% of the total air flow to the primary fuel and air mixing duct, supplying about 5% of the total air flow to the secondary fuel and air mixing duct, supplying about 10% of the total air flow to the tertiary fuel and air mixing duct and supplying the remainder of the air as dilution and cooling air to the combustion chamber in the first mode of operation.

A method of operating a combustion chamber assembly comprising a combustion chamber having a primary combustion zone, a secondary combustion zone and a tertiary combustion zone, at least one primary fuel and air mixing duct, primary fuel injector means to supply fuel to the primary fuel and air mixing duct, first valve means to control the supply of air to the at least one primary fuel and air mixing duct, the primary fuel and air mixing duct being arranged to supply fuel and air into the primary combustion zone, at least one secondary fuel and air mixing duct, secondary fuel injector means to supply fuel to the secondary fuel and air mixing duct, second valve means to control the supply of air to the secondary fuel and air mixing duct, the secondary fuel and air mixing duct being arranged to supply fuel and air into the secondary combustion zone, a tertiary fuel and air mixing duct and the method comprising closing the first valve means and second valve means in a first mode of operation, opening the first valve means and maintaining the second valve means closed in a second mode of operation and opening the first valve means and the second valve means in a third mode of operation, supplying about 10% of the total air flow to the primary fuel and air mixing duct, supplying about 5% of the total air flow to the secondary fuel and air mixing duct, supplying about 10% of the total air flow to the tertiary fuel and air mixing duct and supplying the remainder of the air as dilution and cooling air to the combustion chamber in the second mode of operation.

A method of operating a combustion chamber assembly comprising a combustion chamber having a primary combustion zone, a secondary combustion zone and a tertiary combustion zone, at least one primary fuel and air mixing duct, primary fuel injector means to supply fuel to the primary fuel and air mixing duct, first valve means to control the supply of air to the at least one primary fuel and air mixing duct, the primary fuel and air mixing duct being arranged to supply fuel and air into the primary combustion zone, at least one secondary fuel and air mixing duct, secondary fuel injector means to supply fuel to the secondary fuel and air mixing duct, second valve means to control the supply of air to the secondary fuel and air mixing duct, the secondary fuel and air mixing duct being arranged to supply fuel and air into the secondary combustion zone, a tertiary fuel and air mixing duct and the method comprising closing the first valve means and second valve means in a first mode of operation, opening the first valve means and maintaining the second valve means closed in a second mode of operation and opening the first valve means and the second valve means in a third mode of operation, supplying about 10% of the total air flow to the primary fuel and air mixing duct, supplying about 10% of the total air flow to the secondary fuel and air mixing duct, supplying about 10% of the total air flow to the tertiary fuel and air mixing duct and supplying the remainder of the air as dilution and cooling air to the combustion chamber in the third mode of operation.

A method of operating a combustion chamber assembly comprising a combustion chamber having a primary combustion zone, a secondary combustion zone and a tertiary combustion zone, at least one primary fuel and air mixing duct, primary fuel injector means to supply fuel to the primary fuel and air mixing duct, first valve means to control the supply of air to the at least one primary fuel and air mixing duct, the primary fuel and air mixing duct being arranged to supply fuel and air into the primary combustion zone, at least one secondary fuel and air mixing duct, secondary fuel injector means to supply fuel to the secondary fuel and air mixing duct, second valve means to control the supply of air to the secondary fuel and air mixing duct, the secondary fuel and air mixing duct being arranged to supply fuel and air into the secondary combustion zone, a tertiary fuel and air mixing duct, a tertiary fuel injector means to supply fuel to the tertiary fuel and air mixing duct and the method comprising closing the first valve means and second valve means in a first mode of operation, opening the first valve means and maintaining the second valve means closed in a second mode of operation and opening the first valve means and the second valve means in a third mode of operation, measuring the flow rate of air supplied to the primary fuel and air mixing duct, measuring the flow rate of air supplied to the secondary fuel and air mixing duct, measuring the flow rate of air supplied to the tertiary fuel and air mixing duct, adjusting the flow rate of fuel to the primary fuel injector means to maintain a first predetermined fuel to air ratio in the primary fuel and air mixing duct, adjusting the flow rate of fuel to the secondary fuel injector means to maintain a second predetermined fuel to air ratio in the secondary fuel and air mixing duct, and adjusting the flow rate of fuel to the tertiary fuel injector means to maintain a third predetermined fuel to air ratio in the tertiary fuel and air mixing duct.