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DE-102024133092-A1 - Combustion chamber for a gas turbine and engine

DE102024133092A1DE 102024133092 A1DE102024133092 A1DE 102024133092A1DE-102024133092-A1

Abstract

The invention relates to a combustion chamber (10) for a gas turbine, in particular an aircraft engine, which is in particular designed as an annular circumferential chamber, with an outer wall (6) and an inner wall (7) which are arranged with respect to a longitudinal axis (M) extending between them, and with a front plate (4) extending on the inlet side between the outer wall (6) and the inner wall (7), in particular orthogonally to the longitudinal axis (M), wherein the outer wall (6), the inner wall (7) and the front plate (4) define a combustion chamber (1), in particular an annular circumferential chamber, wherein the combustion chamber (1) extends over a length (L) of the combustion chamber (10), from an injector-side inlet side (13) with an inlet-side height (h1) to a downstream outlet opening (14) with an outlet-side height (h2). An optimized emission characteristic during operation can be achieved by ensuring that, in a longitudinal section through the combustion chamber (10), the outer wall (6) and/or the inner wall (7) have a course that continuously and strictly monotonically approximates the longitudinal axis (M) in the direction of flow, with the approximation being more pronounced at the inlet side (13) than at the outlet side.

Inventors

  • Carsten Clemen
  • Ruud EGGELS
  • Miklos Gerendas

Assignees

  • ROLLS-ROYCE DEUTSCHLAND LTD & CO KG

Dates

Publication Date
20260513
Application Date
20241112

Claims (9)

  1. Combustion chamber (10) for a gas turbine, in particular an aircraft engine, which is in particular designed as an annular circumferential structure, comprising an outer wall (6) and an inner wall (7) arranged with respect to a longitudinal axis (M) extending between them, and a front plate (4) extending on the inlet side between the outer wall (6) and the inner wall (7), in particular orthogonally to the longitudinal axis (M), wherein the outer wall (6), the inner wall (7) and the front plate (4) define a combustion chamber (1), in particular annular in shape, wherein the combustion chamber (1) extends over a length (L) of the combustion chamber (10), from an injector-side inlet side (13) with an inlet-side height (h1) to a downstream outlet opening (14) with an outlet-side height (h2), characterized in that in a longitudinal section through the combustion chamber (10) the outer wall (6) and/or the The inner wall (7) has a course that approaches the longitudinal axis (M) continuously and strictly monotonically in the direction of flow, with the approach being more pronounced at the inlet side (13) than at the outlet side.
  2. combustion chamber (10) after Claim 1 , characterized in that the course of the outer wall (6) and/or the inner wall (7) in longitudinal section is elliptical arc-shaped and/or circular arc-shaped on a circular arc (K).
  3. combustion chamber (10) after Claim 2 , characterized in that, in the case of a circular arc, the circular arc (K) has a radius between 3.5 times and 10 times the length (L), in particular between 5 times and 8 times the length (L), and in the case of an elliptical arc, a first radius is between 80% and 100% and a second radius is between 100% and 120% of the circular radius.
  4. combustion chamber (10) after Claim 3 , characterized in that the outer wall (6) and the inner wall (7) have the same radius of circle and/or the same first radius and second radius, and in particular are arranged in a mirror-symmetrical manner with respect to the longitudinal axis (M).
  5. Combustion chamber (10) according to one of the preceding claims, characterized in that the ratio of the inlet-side height (h1) to the outlet-side height (h2) is between 1.4 and 1.6, preferably 1.5.
  6. Combustion chamber (10) according to one of the preceding claims, characterized in that an angle (α) between the front plate (4) and the outer wall (6) and/or the inner wall (7) is between 45° and 90°, in particular between 60° and 90°.
  7. Combustion chamber (10) according to one of the preceding claims, characterized in that the length (L) between the inlet-side height (h1) and the outlet-side height (h2) is designed according to the specification 1 ≤ L/h1 ≤ 3, in particular 1.6 ≤ L/h1 ≤ 2.3 or 1 ≤ L/h1 ≤ 2.3.
  8. Combustion chamber (10) according to one of the preceding claims, characterized in that the combustion chamber (10) is designed to be mounted at the end.
  9. Engine with a combustion chamber arrangement (100) comprising at least one injector (2) and a combustion chamber (10) according to one of the preceding claims.

Description

The invention relates to a combustion chamber for a gas turbine, in particular an aircraft engine, which is preferably designed as an annular chamber, comprising an outer wall and an inner wall arranged with respect to a longitudinal axis extending between them, and a front plate extending on the inlet side between the outer wall and the inner wall, preferably orthogonal to the longitudinal axis, wherein the outer wall, the inner wall, and the front plate define a combustion chamber, preferably annular in shape, the combustion chamber extending over a length of the combustion chamber, from an injector-side inlet with an inlet-side height to a downstream outlet with an outlet-side height. The invention further relates to an engine. Such a combustion chamber is in the EP 1 522 792 B1 specified, which shows an RQL (Rich Quech Lean) combustion chamber. Additional combustion chambers for an aircraft engine are located in the EP 1 775 516 A2 and the EP 3 321 584 A1 specified. The invention is based on the objective of providing a combustion chamber of the type mentioned above and an engine with optimized emission characteristics in operation. The invention is solved for the combustion chamber with the features of claim 1 and for the engine with the features of claim 9. The combustion chamber is designed so that, in a longitudinal section through the combustion chamber, the outer wall and/or the inner wall have a course that approaches the longitudinal axis in the (main) flow direction (or axial direction with respect to the longitudinal axis) continuously (without kinks and/or jumps) and strictly monotonically (continuously), with the approach being more pronounced at the inlet side than at the outlet side (with the outlet opening). The approach can be interpreted mathematically as a slope or gradient relative to the longitudinal axis. If the longitudinal axis in the longitudinal section were to form an abscissa of a Cartesian coordinate system (with, for example, an ordinate positioned at the inlet side), the cut edges of the outer and/or inner walls would correspond to strictly monotonically sloping, continuous curves, with a continuously decreasing slope from the inlet side towards the outlet opening; that is, the gradient is greatest at the inlet side. The longitudinal axis runs, in particular, centrally through the front plate, which is arranged, in particular, orthogonally to it. Preferably, an injector main body of at least one injector of the combustion chamber arrangement, to which the combustion chamber is assigned, is also arranged along and/or symmetrically on and/or with respect to the longitudinal axis. The inlet height is measured at the axial position of the front plate (on its side facing the combustion chamber) from the outer wall to the inner wall, perpendicular to the longitudinal axis. The outlet height is measured at the axial position of the outlet opening from the outer wall to the inner wall, perpendicular to the longitudinal axis. By definition, the exhaust opening is located in an exhaust plane oriented orthogonally to the longitudinal axis and between the combustion chamber walls. The exhaust opening extends from the downstream end of the outer wall to the downstream end of the inner wall. If the downstream ends are located at different axial positions, the exhaust opening extends from the downstream end of the combustion chamber wall that terminates further upstream (outer or inner wall) to the other combustion chamber wall (inner or outer wall), meaning that one of the combustion chamber walls can project axially beyond the exhaust opening. The front panel can have heat protection on the combustion chamber side and can be single-walled and/or double-walled. The outer wall and/or the inner wall can be single-walled or double-walled. In a combustion chamber with an annular circumference, the longitudinal section is particularly parallel to a central longitudinal axis around which the combustion chamber is arranged. Preferably, the combustion chamber is rotationally symmetrical, with the inventive design of the outer wall and/or the inner wall being present over the entire direction of rotation. The longitudinal axis forms a longitudinal surface around the circumference, which in particular (with respect to the central longitudinal axis) runs radially centrally and/or orthogonally to the front plate. The shaping of the combustion chamber walls (the outer wall and/or the inner wall) according to the invention results in an advantageous Flow control is achieved by avoiding backflow regions induced by abrupt changes in the combustion chamber wall design, which are associated with increased flow residence time and thus nitrogen oxide formation. In this way, the proposed combustion chamber wall design contributes to low nitrogen oxide emissions during operation. Particularly preferred is the longitudinal profile of the outer wall and/or the inner wall in an elliptical arc shape and/or a circ