Alstom Technology Limited

Ansaldo Energia Switzerland Ag

Valter Bellucci

Bruno Schuermans

Christian Oliver Paschereit

Peter Flohr

Majed Toqan

Jonas Hurter

Ken-Yves Haffner

Alexander Ni

Joerg Pross

Francois Meili

Daniele Tabacco

A combustion chamber (), in particular in a gas turbine, has at least two burners (A-H) that are connected to a fuel supply () via controllable fuel valves (' and). Each burner (A to H) is assigned at least one optical measuring device () for detecting chemiluminescent radiation, and the combustion chamber () is assigned a pressure sensor () for detecting a combustion chamber pressure. The optical measuring device () and the pressure sensor () are connected to a computing and control device, which calculates a correlation value from the incoming measured values. A high correlation value signifies that the associated burner is prone to pulsation. The computing and control device () is designed in such a way that it determines the burner or a burner group with the highest correlation and controls the associated fuel valve(s) in such a way that more fuel is fed to the respective burner or the respective burner group, and the pulsation tendency thereof is thereby reduced.

Combustion chamber

A premix burner has a swirl generator and two perforated through flow elements are arranged at a defined distance from one another in the inflow region for the combustion air. The through flow elements are preferably arranged in such a way that substantially the entire combustion airstream has to flow through the through flow elements. The degree of perforation of the through flow elements and the distance between these elements are preferably adapted to one another in such a way that a reflection free condition for combustion pulsation frequencies which may be expected is present at the exit from the burner into the combustion chamber.

Premix burner

Combustion driven pressure pulsations may limit the range of operating conditions where a modern gas turbine can operate with low emission and high efficiency performance. The control of acoustic vibrations has been consequently growing as an essential issue in gas turbine design, development and maintenance. The basic idea of the present invention is to use cooling air leakage through the gaps () of combustor liner segments () to get acoustic damping of combustion pulsations. The main component of the design is the sealing device () which covers the gap () between the two liner segments () and (). The sealing device () collects in the plenum () some of the cooling air () flowing between the outer casing () and the inner liner structure (). For this purpose the sealing device () is provided with openings () along the side walls () which allow the cooling air () to enter the plenum (). In the plenum () the cooling air () is distributed along the gap () and discharged through openings (), distributed along the top side () of the sealing device (). The jets () discharged through the openings () achieve the additional effect to dampen acoustic pulsations in the combustion chamber ().

Device for efficient usage of cooling air for acoustic damping of combustion chamber pulsations

A reheat combustion system for a gas turbine comprises a mixing tube adapted to be fed by products of a primary combustion zone of the gas turbine and by fuel injected by a lance; a combustion chamber fed by the said mixing tube; and at least one perforated acoustic screen. The or each said acoustic screen is provided inside the mixing tube or the combustion chamber, at a position where it faces, but is spaced from, a perforated wall thereof. In use, the perforated wall experiences impingement cooling as it admits air into the combustion system for onward passage through the perforations of the said acoustic screen, and the acoustic screen damps acoustic pulsations in the mixing tube and combustion chamber.

Reheat combustion system for a gas turbine

Growing community of inventors

Fislisbach, Switzerland

Valter Bellucci