Patent Description:
Accordingly, it is desirable to provide a float wall liner that is more robust to minimize thermal mechanical fatigue cracking of the coating.

According to the present invention, a wall panel assembly is as recited in claim <NUM> is provided.

Optionally, an overall thickness of a combination the first coating and the second coating may vary axially based on a ramp function.

Optionally, the overall thickness may vary axially based on a sinusoidal function.

The subject matter which is regarded as the present invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the present invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:.

Referring now to the Figures, where the present invention will be described with reference to specific embodiments, by way of example only. It is to be understood that the disclosed embodiments are merely illustrative and may be embodied in various and alternative forms. The Figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present disclosure.

Referring to <FIG>, a partial sectional view of a portion of gas turbine engine <NUM> is shown. The portion of the gas turbine engine <NUM> includes at least a portion of a combustor section <NUM> and a vane <NUM> of the combustor section <NUM> or a turbine section that is disposed downstream of the combustor section <NUM>.

The combustor section <NUM> includes an annular shell <NUM> and a wall panel assembly <NUM>. The annular shell <NUM> extends axially and circumferentially between a fuel nozzle assembly <NUM> and the vane <NUM>. The fuel nozzle assembly <NUM> is configured to mix and ignite compressed air that is delivered to the combustor section <NUM> with fuel to generate a flame and/or hot combustion gases <NUM> that are contained within the annular shell <NUM> and pass through the vane <NUM> and into the turbine section.

The annular shell <NUM> may be formed of the plurality of axially and/or circumferentially arranged shell sections that are contiguous or joined together. The annular shell <NUM> includes an annular shell inner surface <NUM> and an annular shell outer surface <NUM> that is disposed opposite the annular shell inner surface <NUM>. The annular shell inner surface <NUM> and the outer annular shell surface <NUM> each extend axially and circumferentially between the fuel nozzle assembly <NUM> and the vane <NUM>.

The annular shell <NUM> defines at least one mounting hole <NUM> and at least one cooling hole <NUM>. The at least one mounting hole <NUM> extends from the annular shell outer surface <NUM> to the annular shell inner surface <NUM>. The at least one cooling hole <NUM> is spaced apart from the at least one mounting hole <NUM>. The at least one cooling hole <NUM> is disposed substantially parallel to the at least one mounting hole <NUM>, as shown in <FIG>. In at least one embodiment, a plurality of cooling holes may be provided in the annular shell <NUM>. The plurality of cooling holes are disposed about and are axially and circumferentially spaced apart from the at least one mounting hole <NUM>.

The wall panel assembly <NUM> is operatively connected to the annular shell <NUM>. The wall panel assembly <NUM> is configured to provide thermal protection for the annular shell <NUM> from the combustion gases that are contained within the annular shell <NUM>. The wall panel assembly <NUM> includes a first liner panel <NUM>, a grommet <NUM> (see <FIG>), a stud <NUM>, a coating <NUM> (see <FIG>), and a second liner panel <NUM>.

The first liner panel <NUM> includes a first liner panel inner surface <NUM>, a first liner panel outer surface <NUM>, a first liner panel first side <NUM>, and a first liner panel second side <NUM>. The first liner panel inner surface <NUM> is disposed opposite and is radially spaced apart from the first liner panel outer surface <NUM>. The first liner panel inner surface <NUM> and the first liner panel outer surface <NUM> are each disposed substantially parallel to the annular shell inner surface <NUM>. The first liner panel inner surface <NUM> and the first liner panel outer surface <NUM> each axially extend between a first liner panel first end <NUM> and a first liner panel second end <NUM> that is disposed opposite the first liner panel first end <NUM>. The first liner panel inner surface <NUM> and the first liner panel outer surface <NUM> each circumferentially extend between the first liner panel first side <NUM> and the first liner panel second side <NUM>.

Cooling air may enter through the at least one cooling hole <NUM> and impinge on the first liner panel outer surface <NUM>. The cooling air may be fed from a region external to the combustor section <NUM> having a temperature less than the temperature of the combustion gases contained within the combustor section <NUM> to cool the first liner panel <NUM>. Referring to <FIG> and <FIG>, a plurality of cooling pins <NUM> are disposed on the first liner panel outer surface <NUM>. The plurality of cooling pins <NUM> extend from the first liner panel outer surface <NUM> towards the annular shell inner surface <NUM>. The plurality of cooling pins <NUM> are configured to increase the surface area of the first liner panel <NUM> to improve heat transfer from the first liner panel <NUM>. The plurality of cooling pins <NUM> are spaced apart from and do not engage the annular shell inner surface <NUM> by the grommet <NUM>.

The grommet <NUM> is disposed on the first liner panel outer surface <NUM>. The grommet <NUM> is configured to space the plurality of cooling pins <NUM> apart from the annular shell inner surface <NUM>. The grommet <NUM> may engage the first liner panel outer surface <NUM> and the annular shell inner surface <NUM>. The grommet <NUM> sets a spacing or distance between the first liner panel <NUM> and the first liner panel outer surface <NUM> and the annular shell inner surface <NUM>.

The stud <NUM> is configured to operatively connect the first liner panel <NUM> to the annular shell <NUM>. The stud <NUM> extends from the first liner panel outer surface <NUM> and is received in the at least one mounting hole <NUM> of the annular shell <NUM> such that the stud <NUM> extends completely through the annular shell inner surface <NUM> and the annular shell outer surface <NUM>. The stud <NUM> may be a fastener, a pin, or the like that is secured to the annular shell by a nut or the like that is disposed on the annular shell outer surface <NUM>.

Referring to <FIG> and <FIG>, the first liner panel <NUM> is provided with a plurality of liner panel cooling holes <NUM>. The plurality of liner panel cooling holes <NUM> extend from the first liner panel outer surface <NUM> towards the first liner panel inner surface <NUM>. The plurality of liner panel cooling holes <NUM> are configured to receive the cooling air that enters through the at least one cooling hole <NUM> to aid in cooling the first liner panel <NUM>. At least one liner panel cooling hole of the plurality of liner panel cooling holes <NUM> is proximately aligned with the at least one cooling hole <NUM> such that an outlet of the at least one cooling hole <NUM> directly flows into an inlet of at least one liner panel cooling hole of the plurality of liner panel cooling holes <NUM>. The plurality of liner panel cooling holes <NUM> are disposed at an angle relative to the at least one cooling hole <NUM> of the annular shell <NUM>. The plurality of liner panel cooling holes <NUM> are disposed in a non-parallel relationship relative to the at least one cooling hole <NUM> of the annular shell <NUM>. The plurality of liner panel cooling holes <NUM> may be provided in conjunction with the plurality of cooling pins <NUM> or may be provided as an alternative to the plurality of cooling pins <NUM>.

With continued reference to <FIG> and <FIG>, the first liner panel <NUM> includes a first arm <NUM> and a second arm <NUM>. The first arm <NUM> is disposed proximate the first liner panel first end <NUM> and extends towards the annular shell inner surface <NUM>. The first arm <NUM> is spaced apart from the annular shell inner surface <NUM>. The second arm <NUM> is disposed proximate the first liner panel second end <NUM> and extends towards the annular shell inner surface <NUM>. The second arm <NUM> is spaced apart from the annular shell inner surface <NUM>. The grommet <NUM> may be provided and aids in spacing the first arm <NUM> and the second arm <NUM> from the shell inner surface <NUM>.

Referring to <FIG>, the coating <NUM> is applied to the first liner panel <NUM>. The coating <NUM> is disposed on the first liner panel inner surface <NUM>, and may optionally be disposed on the first liner panel outer surface <NUM>. In at least one embodiment, the coating <NUM> is applied to the first liner panel inner surface <NUM> and the first liner panel outer surface <NUM> such that the first liner panel inner surface <NUM> and the first liner panel outer surface <NUM> is coated by the coating <NUM>. In at least one embodiment, the coating <NUM> is applied to the first liner panel inner surface <NUM> such that the first liner panel inner surface <NUM> is coated by the coating <NUM> and the first liner panel outer surface <NUM> is uncoated or not coated by the coating <NUM>. The coating <NUM> is a thermal barrier coating that is configured to provide thermal protection to the first liner panel <NUM>. The combination of the coating <NUM> and the cooling air that enters through the at least one cooling hole <NUM> and impinges or flows through the first liner panel <NUM> controls the temperature of the first liner panel <NUM> and ultimately the annular shell <NUM>. The constraining of the first liner panel <NUM> with the annular shell <NUM> by the stud <NUM> and temperature differences due to the cooling air that impinges or flows through the first liner panel <NUM> may result in high thermal stresses that may lead to thermal mechanical fatigue cracking of at least one of the coating <NUM> and the first liner panel <NUM>. For example, the first liner panel first end <NUM> may be cooler as compared to the first liner panel second end <NUM> due to the cooling air provided through the at least one cooling hole <NUM> impinging closer to the first liner panel first end <NUM> than the first liner panel second end <NUM>.

The coating <NUM> is applied to the first liner panel inner surface <NUM>, and may optionally be applied to the first liner panel outer surface <NUM>, such that it has a varying or variable overall thickness in the circumferential direction, and optionally the axial direction, of the first liner panel <NUM> to control the temperature of the first liner panel <NUM>.

The overall thickness of the coating <NUM> may be thinner proximate areas of the first liner panel <NUM> that are disposed proximate the at least one cooling hole <NUM> of the annular shell <NUM> and may be thicker proximate areas of the first liner panel <NUM> that are spaced apart from the at least one cooling hole <NUM> of the annular shell <NUM>. Additionally, the overall thickness of the coating <NUM> may be thicker proximate areas of the first liner panel <NUM> that are disposed closer to the flame or hot combustion gases and may be thinner proximate areas of the first liner panel <NUM> that are disposed further from the flame or hot combustion gases.

The coating <NUM> may have a variable nominal overall thickness distribution to reduce thermal gradients and results in a more isothermal design of the first liner panel <NUM>. Ultimately, the coating <NUM> having a variable nominal overall thickness distribution improves service life of the combustor section <NUM> and the overall gas turbine engine. The coating <NUM> may also reduce overhaul and repair costs for the gas turbine engine <NUM>.

The coating <NUM> includes a first coating <NUM> and a second coating <NUM>. The first coating <NUM> is disposed on the first liner panel inner surface <NUM>, and optionally on the first liner panel outer surface <NUM>. The first coating <NUM> may be a metallic bond coating to aid in bonding the second coating <NUM> to at least one of the first coating <NUM> and the first liner panel inner surface <NUM> and/or the first liner panel outer surface <NUM>. The second coating <NUM> is disposed on the first coating <NUM> and may be an applied ceramic-based coating, a thermal barrier coating, a flame sprayed ceramic, or the like. A combination of the first coating <NUM> and the second coating <NUM> defines the overall thickness of the coating <NUM>. The thickness of at least one of the first coating <NUM> and the second coating <NUM> is varied circumferentially, and may optionally be varied axially, over the first liner panel inner surface <NUM> to vary the overall thickness of the coating <NUM> circumferentially, and optionally axially, over the first liner panel inner surface <NUM>. The thickness of at least one of the first coating <NUM> and the second coating <NUM> may be varied axially and/or circumferentially over the first liner panel outer surface <NUM> to vary the overall thickness of the coating <NUM> axially and/or circumferentially over the first liner panel outer surface <NUM>.

The coating <NUM> defines a first overall thickness, t<NUM>, that is disposed proximate the first liner panel first end <NUM>, a second overall thickness, t<NUM>, that is disposed proximate the first liner panel second end <NUM>, and an overall thickness, t<NUM>, that extends or is disposed between the first liner panel first end <NUM> and the first liner panel second end <NUM>. The first overall thickness, t<NUM>, is different from the second overall thickness, t<NUM>.

As shown in <FIG>, the first overall thickness, t<NUM>, varies circumferentially in a direction that extends between the first liner panel first side <NUM> and the first liner panel second side <NUM>.

The second overall thickness, t2, may be substantially constant circumferentially in a direction that extends between the first liner panel first side <NUM> and the first liner panel second side <NUM>. As shown in <FIG>, the second overall thickness, t<NUM>, may vary circumferentially in a direction that extends between the first liner panel first side <NUM> and the first liner panel second side <NUM>.

As shown in <FIG>, the overall thickness, t<NUM>, of the coating <NUM> varies between the first liner panel first end <NUM> and the first liner panel second end <NUM> according to a ramp function. The ramp function increases the overall thickness, t<NUM>, of the coating <NUM> in the axial direction from the first liner panel first end <NUM> and the first liner panel second end <NUM> such that the second overall thickness, t<NUM>, is greater than the first overall thickness, t<NUM>. In at least one embodiment, the ramp function increases the overall thickness, t<NUM>, of the coating <NUM> in the circumferential direction from the first liner panel first side <NUM> and the first liner panel second side <NUM>.

As shown in <FIG>, the overall thickness, t<NUM>, of the coating <NUM> varies between the first liner panel first end <NUM> and the first liner panel second end <NUM> according to a sinusoidal or pseudo-sinusoidal function. The sinusoidal or pseudo-sinusoidal function increases and decreases the overall thickness, t<NUM>, of the coating <NUM> in the axial direction from the first liner panel first end <NUM> and the first liner panel second end <NUM> based on a sine or cosine between coating thickness and axial position. In at least one embodiment, the sinusoidal or pseudo-sinusoidal function increases and decreases the overall thickness, t<NUM>, of the coating <NUM> in the circumferential direction from the first liner panel first side <NUM> and the first liner panel second side <NUM> based on a sine or cosine relationship between coating thickness and circumferential position.

As shown in <FIG>, the overall thickness, t<NUM>, of the coating <NUM> varies between the first liner panel first end <NUM> and the first liner panel second end <NUM> according to an arbitrary or random function. The arbitrary or random function increases and/or decreases the overall thickness, t<NUM>, of the coating <NUM> in the axial direction from the first liner panel first end <NUM> and the first liner panel second end <NUM>. In at least one embodiment, the arbitrary or random function increases and/or decreases the overall thickness, t<NUM>, of the coating <NUM> in the circumferential direction from the first liner panel first side <NUM> and the first liner panel second side <NUM>.

Referring to <FIG>, the second liner panel <NUM> is operatively connected to the annular shell <NUM>. The second liner panel <NUM> is disposed proximate the first liner panel <NUM>. The second liner panel <NUM> includes a second liner panel inner surface <NUM>, a second liner panel outer surface <NUM>, a second liner panel first side <NUM>, and a second liner panel second side <NUM>. The second liner panel inner surface <NUM> is disposed opposite and is radially spaced apart from the second liner panel outer surface <NUM>. The second liner panel inner surface <NUM> and the second liner panel outer surface <NUM> are each disposed substantially parallel to the annular shell inner surface <NUM>. The second liner panel inner surface <NUM> and the second liner panel outer surface <NUM> each axially extend between a second liner panel first end <NUM> and a second liner panel second end <NUM> that is disposed opposite the second liner panel first end <NUM>. The second liner panel inner surface <NUM> and the second liner panel outer surface <NUM> each circumferentially extend between the second liner panel first side <NUM> and the second liner panel second side <NUM>. The second liner panel <NUM> has a substantially similar configuration to the first liner panel <NUM> and may also include the coating <NUM> that is disposed on the second liner panel inner surface <NUM>.

As shown in <FIG> and <FIG>, the second liner panel second end <NUM> axially overlaps the first liner panel first end <NUM>. The second liner panel second end <NUM> is radially spaced apart from the first liner panel first end <NUM> and defines a gap <NUM> therebetween. The cooling air that enters through the at least one cooling hole <NUM> may flow through the gap <NUM> and cool at least one of the second liner panel second end <NUM> and the first liner panel first end <NUM>.

As shown in <FIG> and <FIG>, the second liner panel <NUM> includes a first arm <NUM> and a second arm <NUM>. The first arm <NUM> is disposed proximate the second liner panel first end <NUM> and extends towards the annular shell inner surface <NUM>. The first arm <NUM> is configured to engage the annular shell inner surface <NUM>. The second arm <NUM> is disposed proximate the second liner panel second end <NUM> and extends towards the annular shell inner surface <NUM>. The second arm <NUM> is configured to engage the annular shell inner surface <NUM>. The second liner panel second end <NUM> abuts the first liner panel first end <NUM> such that the second arm <NUM> of the second liner panel <NUM> abuts the first arm <NUM> of the first liner panel <NUM>.

Throughout this specification, the term "attach," "attachment," "connected", "coupled," "coupling," "mount," or "mounting" shall be interpreted to mean that a structural component or element is in some manner connected to or contacts another element, either directly or indirectly through at least one intervening structural element, or is integrally formed with the other structural element.

Claim 1:
A wall panel assembly (<NUM>) comprising:
a first liner panel (<NUM>) operatively connected to an annular shell (<NUM>), the first liner panel (<NUM>) having a first liner panel inner surface (<NUM>) and a first liner panel outer surface (<NUM>), the first liner panel inner surface (<NUM>) extending between a first liner panel first end (<NUM>) and a first liner panel second end (<NUM>), the first liner panel outer surface (<NUM>) being disposed opposite the first liner panel inner surface (<NUM>) and extending between the first liner panel first end (<NUM>) and the first liner panel second end (<NUM>),
a first coating (<NUM>) disposed on the first liner panel inner surface (<NUM>);
a second coating (<NUM>) disposed on the first coating (<NUM>), wherein a combination of the first coating (<NUM>) and the second coating (<NUM>) has a first overall thickness (t<NUM>) that is disposed proximate the first liner panel first end (<NUM>) and a second overall thickness (t<NUM>) that is disposed proximate the first liner panel second end (<NUM>), and wherein the first thickness (t<NUM>) is different from the second thickness (t<NUM>); and
a second liner panel (<NUM>) that is operatively connected to the annular shell (<NUM>), the second liner panel (<NUM>) having a second liner panel inner surface (<NUM>) extending between a second liner panel first end (<NUM>) and a second liner panel second end (<NUM>), and a second liner panel outer surface (<NUM>) disposed opposite the second liner panel inner surface (<NUM>) and extending between the second liner panel first end (<NUM>) and the second liner panel second end (<NUM>), wherein the second liner panel second end (<NUM>) axially overlaps the first liner panel first end (<NUM>) and is radially spaced apart from the first liner panel first end (<NUM>),
wherein the first liner panel (<NUM>) has a first liner panel first side (<NUM>) that extends between the first liner panel first end (<NUM>) and the first liner panel second end (<NUM>) and a first liner panel second side (<NUM>) that extends between the first liner panel first end (<NUM>) and the first liner panel second end (<NUM>), and
wherein the first overall thickness (t<NUM>) varies circumferentially between the first liner panel first side (<NUM>) and the first liner panel second side (<NUM>).