Turbine engine seal for turbine engine

Abstract

A turbine engine seal configured for use between a turbine engine rotor and a turbine engine static component of a turbine engine may include a sealing structure having a negative thermal expansion (NTE) layer on one or both of the turbine engine rotor and the turbine engine static component. The NTE layer may include an NTE reactive feature that includes a material having a negative coefficient of thermal expansion. When the turbine engine rotor rubs against the turbine engine static component, heat is generated, and the NTE reactive component experiences a temperature rise from a first temperature to a second temperature. The increase in temperature results in a reduction in size of the NTE-reactive component, thereby forming a hydrodynamic pouch that can be used to generate a lift that propels the separation between the turbine engine rotor and the turbine engine static component. The sealing structure may include a lattice compliant layer.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to seal assemblies for rotary machines, and more particularly, to seals for rotary machines, such as turbine engines, and methods of manufacturing seal assemblies and facilitating separation between a turbine engine rotor and a turbine engine static component. BACKGROUND

[0002] Rotary machines, such as gas turbine engines, have seals between a rotating component (e.g., a rotor) and a corresponding stationary component (e.g., a stator). These seals help reduce fluid leakage between the rotor and the stator. Transient operating conditions and / or abnormal movement of the rotor can cause leakage of the seals. Excessive leakage of the seals in a rotary machine can significantly reduce the operating efficiency of the rotary machine. Transient operating conditions and / or abnormal movement of the rotor can also cause increased friction and / or contact between the seals and the rotor. This friction and / or contact between the seals and the rotor can cause premature wear and / or reduced operating efficiency of the rotary machine. Accordingly, it would be desirable to provide improved seal assemblies for rotary machines, such as turbine engines, and improved methods of sealing an interface between a rotor and a stator of a rotary machine. BRIEF DESCRIPTION OF DRAWINGS

[0003] A complete and enabling disclosure is set forth in the specification of this patent document, including the best mode for carrying out the application, of which the following examples are representative, in which:

[0004] Figure 1 A schematic cross-sectional view of an exemplary turbine engine is shown;

[0005] Figure 2 A schematic view of an exemplary seal assembly disposed between a turbine engine rotor and a turbine engine static component is shown;

[0006] Figure 3A A schematic view of an exemplary seal structure of a seal assembly at a first temperature is shown;

[0007] Figure 3B A schematic view of an exemplary seal structure of a seal assembly at a first temperature is shown;

[0008] Figure 4A And Figure 4B A schematic view of an exemplary seal structure of a seal assembly at a second temperature is shown;

[0009] Figure 4B A schematic view of an exemplary seal structure of a seal assembly at a second temperature is shown;

[0010] Figure 5 A schematic view of another exemplary seal structure at a first temperature is shown;

[0011] Figure 6 a schematic diagram showing another exemplary seal structure having a lattice compliant layer; Figure 6 a schematic diagram showing another exemplary seal structure having a lattice compliant layer;

[0012] Figure 7 a schematic diagram showing another exemplary seal structure having a lattice compliant layer;

[0013] Figure 8 a schematic diagram showing another exemplary seal structure having a lattice compliant layer;

[0014] Figure 9 a schematic diagram showing an annular arrangement of multiple segments of an exemplary seal structure;

[0015] Figure 10 a method of operating a turbine engine having a seal structure; and

[0016] Figure 11 a method of fabricating a seal structure having a lattice compliant layer.

[0017] Reference numbers repeated in the description and drawings are intended to denote the same or similar features or elements in the present disclosure. DETAILED DESCRIPTION

[0018] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the present disclosure and is not meant as a limitation of the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the present disclosure. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield still a further embodiment. Thus, it is intended that the present disclosure cover all such modifications and variations of this disclosure.

[0019] The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations. Furthermore, unless otherwise indicated, all embodiments described herein are to be considered exemplary.

[0020] As used herein, the terms “first,” “second,” and “third” can be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.

[0021] The terms “upper,” “lower,” “right,” “left,” “vertical,” “horizontal,” “top,” “bottom,” “lateral,” “longitudinal,” and the like shall relate to the present disclosure as it is oriented in the drawings. However, it is to be understood that the present disclosure can assume various alternative orientations, unless explicitly stated otherwise. It is also to be understood that the specific devices illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the present disclosure. Hence, specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered as limiting.

[0022] The terms “forward” and “aft” refer to relative positions within a turbine engine, with forward referring to a position closer to the engine inlet and aft referring to a position closer to the engine nozzle or exhaust.

[0023] The terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid path. For example, “upstream” refers to the direction from which fluid flows, and “downstream” refers to the direction to which fluid flows.

[0024] The singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.

[0025] The terms “coupled,” “fixed,” “attached to” and the like, mean either a direct coupling, fixation, or attachment, or an indirect coupling, fixation or attachment through one or more intermediary devices or features, unless specifically stated otherwise herein.

[0026] Approximating language as used herein throughout the description and claims is applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is directed. Accordingly, a value modified by a term or terms, such as “about,” “approximately,” and “substantially,” are not limited to the precise value specified. In at least some instances, an approximation language can correspond to the precision of an instrument for measuring the value or the precision of the method or machine for constructing or manufacturing the component and / or system. For example, an approximation language can refer to within 1%, 2%, 4%, 10%, 15%, or 20% margin of error.

[0027] Herein and throughout the specification and claims, range limitations are combined and interchanged, such ranges are identified and include all the sub-ranges included therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.

[0028] Additionally, unless otherwise noted, the terms "low," "high," or their respective comparative forms (e.g., lower, higher, if applicable) all refer to relative speeds within the engine. For example, a "low pressure turbine" operates at a pressure that is generally lower than a "high pressure turbine." Alternatively, unless otherwise noted, the aforementioned terms can be interpreted in their superlative form. For example, a "low pressure turbine" can refer to the lowest maximum pressure turbine within the turbine section 126, while a "high pressure turbine" can refer to the highest maximum pressure turbine within the turbine section 126.

[0029] The term "turbomachine" or "turbomachinery" refers to a machine that includes one or more compressors, a heat generating section (e.g., a combustor section), and one or more turbines that together generate a torque output.

[0030] As used herein, the term "turbine engine" refers to an engine that includes a turbomachine as all or a portion of its power source. Example turbine engines include gas turbine engines, as well as hybrid electric turbomachines, such as turbofan engines, turboprop engines, turbojet engines, turboshaft engines, and the like.

[0031] As used herein, the term "rotor" refers to any component of a rotating machine (such as a turbine engine) that rotates about an axis of rotation. As an example, a rotor can include a shaft or spool of a rotating machine (such as a turbine engine).

[0032] As used herein, the term "stator" refers to any component of a rotating machine (such as a turbine engine) that has a coaxial construction and arrangement with a rotor of the rotating machine. A stator can be stationary, or can rotate about an axis of rotation. A stator can be disposed radially inward or radially outward relative to a rotor along a radial axis.

[0033] One or more components of the turbomachine engines described below can be manufactured or formed using any suitable process, such as an additive manufacturing process (e.g., a 3D printing process). Using such processes can allow such components to be integrally formed as a single monolithic component, or any suitable number of sub-components. In particular, additive manufacturing processes can allow such components to be integrally formed and include various features that would not be achievable using existing manufacturing methods. For example, the additive manufacturing methods described herein can allow for the manufacture of passages, conduits, cavities, openings, housings, manifolds, double walls, heat exchangers, or other components, or particular positioning and integration of these components, that have unique features, constructions, thicknesses, materials, densities, fluid pathways, headers, and mounting structures that can not be achievable or practical using existing manufacturing methods. Some of these features are described herein.

[0034] Suitable additive manufacturing techniques in accordance with the present disclosure include, for example, selective laser melting (SLM), direct metal laser melting (DMLM), fused deposition modeling (FDM), selective laser sintering (SLS), 3D printing such as by inkjet, laserjet, and binderjet, stereolithography (SLA), direct selective laser sintering (DSLS), electron beam sintering (EBS), electron beam melting (EBM), laser engineered net shaping (LENS), laser net shape manufacturing (LNSM), direct metal deposition (DMD), digital light processing (DLP), direct selective laser melting (DSLM), and other known processes.

[0035] Suitable powder materials for manufacturing the structures provided herein as unitary, single structures include metal alloys, polymeric, or ceramic powders. Exemplary metal powder materials are stainless steel alloys, cobalt-chrome alloys, aluminum alloys, titanium alloys, nickel-based superalloys, and cobalt-based superalloys. Additionally, suitable alloys can include those engineered to have good oxidation resistance, known as "superalloys" having acceptable strength at elevated operating temperatures in turbine engines, for example, Hastelloy, Inconel (e.g., IN 738, IN 792, IN 939), Rene alloys (e.g., Rene N4, Rene N5, Rene 80, Rene 142, Rene 195), Haynes alloys, Mar M, CM 247, CM 247LC, C263, 718, X-850, ECY768, 282, X45, PWA 1483, and CMSX (e.g., CMSX-4) single crystal alloys. Manufactured objects of the present disclosure can be formed from one or more selected crystal microstructures, such as directionally solidified ("DS") or single crystal ("SX").

[0036] As used herein, the terms "unitary," "single," or "monolithic" to describe a structure means that the structure is formed integrally from a continuous material or group of materials, without seams, connecting joints, or the like. The unitary single structures described herein can be formed by additive manufacturing to have the described structure, or alternatively formed by a casting process or the like.

[0037] The present disclosure generally provides a seal assembly for a rotary machine. The presently disclosed seal assembly can be used in any rotary machine. Exemplary embodiments can be particularly suitable for use in a turbomachine, such as a turbine engine or the like. The presently disclosed seal assembly includes a film riding seal that provides a thin film of fluid between a face of the seal and a face of the rotor. The seal assembly can be located at an interface between a turbine engine rotor and a turbine engine static component. The seal assembly can include a seal structure.

[0038] The presently disclosed seal assembly is generally considered to be a non-contact seal in that the fluid bearing inhibits contact between the seal face and the rotor face. Additionally, the presently disclosed seal assembly includes a seal structure configured to float or actuate along a motion axis in response to a motive force caused by a transient operating condition of the rotating machine and / or an abnormal movement of the rotor. The structure includes features described herein that provide improved response to the transient operating condition and / or the abnormal movement of the rotor. The presently disclosed seal structure can accommodate a wider range of operating conditions and / or can provide improved operating performance, including improved seal assembly performance and / or improved rotating machine performance. Additionally or alternatively, the presently disclosed seal assembly can provide a lower likelihood of continuous contact between the turbine engine rotor and the turbine engine static components during transient conditions, thereby improving the durability and / or service life of the seal assembly, the turbine engine rotor, the turbine engine static components, and / or related components of the rotating machine.

[0039] Example embodiments of the present disclosure will now be described in greater detail. Reference will be made to Figure 1 An example turbine engine 100 will be described. In some embodiments, the presently disclosed seal assembly can be included in a rotating machine, such as the turbine engine 100. The example turbine engine 100 can be mounted to an aircraft, such as in a wing under configuration or a tail mounted configuration. It will be understood that Figure 1 The turbine engine 100 shown in FIG. 1 is provided by way of example and not limitation, and the subject matter of the present disclosure can be implemented with other types of turbine engines as well as other types of rotating machines.

[0040] Generally, the turbine engine 100 can include a fan section 102 and a core engine 104 disposed downstream of the fan section 102. The fan section 102 can include a fan 106 having any suitable configuration, such as a single stage configuration with variable pitch. The fan 106 can include a plurality of fan blades 108 coupled to a fan disk 110 in a spaced apart manner. The fan blades 108 can extend outwardly from the fan disk 110 generally along a radial direction. The core engine 104 can be directly or indirectly coupled to the fan section 102 to provide torque for driving the fan section 102.

[0041] The core engine 104 may include an engine housing 114 that surrounds one or more portions of the core engine 104, including a compressor section 122, a combustor section 124, and a turbine section 126. The engine housing 114 may define a core engine inlet 116, an exhaust nozzle 118, and a core airflow path 120 between them. The core airflow path 120 may pass through the compressor section 122, combustor section 124, and turbine section 126 in a series flow relationship. The compressor section 122 may include a first turbocharger or low-pressure (LP) compressor 128 and a second high-pressure (HP) compressor 130. The turbine section 126 may include a first high-pressure (HP) turbine 132 and a second low-pressure (LP) turbine 134. The compressor section 122, combustor section 124, turbine section 126, and exhaust nozzle 118 may be arranged in a series flow relationship and may each define a portion of the core airflow path 120 through the core engine 104.

[0042] The core motor 104 and fan section 102 can be coupled to a shaft driven by the core motor 104. As an example, such as... Figure 1 As shown, the core engine 104 may include a high-pressure (HP) shaft 136 and a low-pressure (LP) shaft 138. The HP shaft 136 can drive the HP turbine 132 to the HP compressor 130. The LP shaft 138 can drive the LP turbine 134 to the LP compressor 128. In other embodiments, such as in the case of a turbine engine 100 including an intermediate-pressure turbine, the turbine engine 100 may have three shafts. The shafts of the core engine 104, together with the rotating portions of the core engine 104, may sometimes be referred to as "spools". The HP shaft 136, the rotating portion of the HP compressor 130 coupled to the HP shaft 136, and the rotating portion of the HP turbine 132 coupled to the HP shaft 136 may be collectively referred to as the high-pressure (HP) spool 140. The LP shaft 138, the rotating portion of the LP compressor 128 coupled to the LP shaft 138, and the rotating portion of the LP turbine 134 coupled to the LP shaft 138 may be collectively referred to as the low-pressure (LP) spool 142.

[0043] In some embodiments, fan section 102 may be directly coupled to the shaft of core engine 104, such as directly coupled to LP shaft 138. Alternatively, as Figure 1 As shown, fan section 102 and core engine 104 can be connected to each other via a power gearbox 144 (such as a planetary reduction gearbox, a rotary gearbox, etc.). For example, power gearbox 144 can connect LP shaft 138 to fan 106, such as fan disc 110 connected to fan section 102. Power gearbox 144 may include multiple gears for reducing the rotational speed of LP shaft 138 to a more efficient rotational speed for fan section 102.

[0044] Still referring to Figure 1 The fan section 102 of the turbine engine 100 can include a fan case 146 at least partially surrounding the fan 106 and / or a plurality of fan blades 108. The fan case 146 can be supported by the core engine 104, for example, by a plurality of outlet guide vanes 148 circumferentially spaced apart and extending substantially radially therebetween. The turbine engine 100 can include a nacelle 150. The nacelle 150 can be fixed to the fan case 146. The nacelle 150 can include one or more sections at least partially surrounding the fan section 102, the fan case 146, and / or the core engine 104. For example, the nacelle 150 can include a nose cowl, a fan cowl, an engine cowl, a thrust reverser, etc. An inner portion of the fan case 146 and / or the nacelle 150 can circumferentially surround an outer portion of the core engine 104. The inner portion of the fan case 146 and / or the nacelle 150 can define a bypass passage 152. The bypass passage 152 can be annularly disposed between the outer portion of the core engine 104 and the inner portion of the fan case 146 and / or the nacelle 150 surrounding the outer portion of the core engine 104.

[0045] During operation of the turbine engine 100, an inlet airflow 154 enters the turbine engine 100 through an inlet 156 defined by the nacelle 150, such as a nose cowl of the nacelle 150. The inlet airflow 154 passes through the fan blades 108. The inlet airflow 154 is split into a core airflow 158 that flows into and through the core air flowpath 120 of the core engine 104 and a bypass airflow 160 that flows through the bypass passage 152. The core airflow 158 is compressed by the compressor section 122. Pressurized air from the compressor section 122 flows downstream to the combustor section 124, where fuel is introduced to generate combustion gases, represented by arrows 162. The combustion gases exit the combustor section 124 and flow through the turbine section 126, generating torque that rotates the compressor section 122 to support combustion, while also rotating the fan section 102. Rotation of the fan section 102 causes the bypass airflow 160 to flow through the bypass passage 152, generating propulsive thrust. The core airflow exiting the exhaust nozzle 118 generates additional thrust.

[0046] In some example embodiments, the turbine engine 100 can be a relatively large power class turbine engine 100 that can generate a relatively large amount of thrust. For example, the turbine engine 100 can be configured to generate a thrust of about 300 kiloNewtons (kN) to a thrust of about 700 kN, such as a thrust of about 300 kN to about 500 kN, such as a thrust of about 500 kN to about 600 kN, or such as a thrust of about 600 kN to about 700 kN. However, it will be understood that reference to a turbine engine 100 generating a thrust of about 300 kN to about 700 kN is not intended to be limiting. Figure 1The various features and attributes of the turbine engine 100 described are provided by way of example only and are not construed to be limiting. Indeed, the present disclosure can be implemented with respect to any desired turbine engine, including those having attributes or features that differ in one or more respects from the turbine engine 100 described herein.

[0047] Still referring to Figure 1 The turbine engine 100 includes sealing assemblies at a plurality of locations throughout the turbine engine 100, any one or more of which can be constructed in accordance with the present disclosure. The presently disclosed sealing assemblies can be provided in the turbine engine 100 at any location, including interfaces with rotating portions of the turbine engine 100, such as interfaces with rotating portions or spools of the core engine 104. For example, a sealing assembly can be included at an interface with a portion of the LP spool 142 and / or at an interface with the HP spool 140. In some embodiments, a sealing assembly can be included at an interface between a spool of the core engine 104, such as the LP spool 142 or the HP spool 140, and a stationary portion. Additionally or alternatively, a sealing assembly can be included at an interface between the LP spool 142 and the HP spool 140. Additionally or alternatively, a sealing assembly can be included at an interface between a stationary portion of the core engine 104 and the LP shaft 138 or the HP shaft 136, and / or at an interface between the LP shaft 138 and the HP shaft 136.

[0048] By way of example, Figure 1Some example locations of seal assemblies are shown. As one example, a seal assembly can be located at or near bearing chamber 164. A seal assembly located at or near bearing chamber 164 can sometimes be referred to as a bearing chamber seal. Such a bearing chamber seal can be configured to inhibit the ingress of an air flow, such as core airflow 158, into a bearing chamber of turbine engine 100, such as a bearing chamber located at an interface between LP shaft 138 and HP shaft 136. As another example, a seal assembly can be located at or near compressor section 122 of turbine engine 100. In some embodiments, a seal assembly can be located at or near a compressor discharge 166 of, for example, HP compressor 130. A seal assembly located at or near compressor discharge 166 can sometimes be referred to as a compressor discharge pressure seal. Such a compressor discharge pressure seal can be configured to maintain a pressure downstream of compressor section 122 and / or to provide bearing thrust balancing. Additionally or alternatively, a seal assembly can be located between adjacent compressor stages 168 of compressor section 122. A seal assembly located between adjacent compressor stages 168 can sometimes be referred to as an inter-compressor stage seal. Such an inter-compressor stage seal can be configured to limit air recirculation within compressor section 122. As another example, a seal assembly can be located at or near turbine section 126 of turbine engine 100. In some embodiments, a seal assembly can be located at or near a turbine inlet 170 of, for example, HP turbine 132 or LP turbine 134. A seal assembly located at or near turbine inlet 170 can sometimes be referred to as a front turbine seal. Such a front turbine seal can be configured to accommodate high pressure cooling air for HP turbine 132 and / or LP turbine 134, such as for turbine disks and turbine blades thereof. Additionally or alternatively, a seal assembly can be located at or near one or more turbine disk rims 172. A seal assembly located at or near turbine disk rim 172 can sometimes be referred to as a turbine disk rim seal. Such a turbine disk rim seal can be configured to inhibit hot gas ingestion into a disk rim region. Additionally or alternatively, a seal assembly can be located between adjacent turbine stages 174 of turbine section 126. A seal assembly located between adjacent turbine stages 174 can sometimes be referred to as an inter-turbine stage seal. Such an inter-turbine stage seal can be configured to limit air recirculation within turbine section 126.

[0049] A seal assembly at any one or more of these locations or other locations of turbine engine 100 can be configured in accordance with the present disclosure. Additionally or alternatively, turbine engine 100 can include a presently disclosed seal assembly at one or more other locations of turbine engine 100. It will also be appreciated that the presently disclosed seal assemblies can also be used in other rotary machines, and reference to turbine engine 100 is made for illustrative purposes only. Figure 1 Turbine engine 100 described is provided as an example and is not to be construed as limiting.

[0050] Reference will now be made to Figure 2 , further describing example sealing assemblies. As shown in Figure 2 , a rotating machine 200, such as a turbine engine 100, can include a sealing assembly 202 configured to provide a sealed interface between a turbine engine rotor 204 and a turbine engine static component 205 of the rotating machine 200. The sealing assembly 202 can be integrated into any rotating machine 200, such as the turbine engine 100 described with reference to Figure 1 . As shown in Figure 2 , the sealing assembly 202 can separate an inlet plenum 206 from an outlet plenum 208. The inlet plenum 206 can define a region of the rotating machine 200 that includes a relatively high pressure fluid volume (p_high). The inlet plenum 206 can be located at a distal position relative to a rotational axis 210 of the rotor 204. The outlet plenum 208 can define a region of the rotating machine 200 that includes a relatively low pressure fluid volume (p_low). The outlet plenum 208 can be located at a proximal position relative to the rotational axis 210 of the rotor 204. The rotational axis 210 can coincide with and / or can extend parallel to a longitudinal axis of the rotating machine 200, such as the turbine engine 100. The sealing assembly 202 can be configured to provide a film riding seal of a non-contacting sealed interface that inhibits contact between the turbine engine static component 205 and the turbine engine rotor 204, such as a fluid bearing, a gas bearing, etc. located at an interface of the turbine engine static component 205 and the turbine engine rotor 204.

[0051] With the above-discussed variety of locations in mind that can be suitable for use with the sealing assembly 202, either or both of the turbine engine static component 205 and the turbine engine rotor 204 that can be used with the sealing assembly 202 can take a variety of forms. In one embodiment, the turbine engine static component 205 can take the form of a turbine engine casing (e.g., a compressor casing, a turbine casing, etc.). In alternative and / or additional embodiments, the turbine engine rotor 204 can take the form of a turbine rotor and / or a compressor rotor. In the illustrated embodiment, the sealing assembly 202 is located on each of the turbine engine static component 205 and the turbine engine rotor 204. In some embodiments, the sealing assembly 202 can be included with only one of the turbine engine static component 205 and the turbine engine rotor 204. Further, in additional and / or alternative embodiments, either or both of the turbine engine static component 205 and the turbine engine rotor 204 can include a plurality of sealing assemblies 202 positioned at different locations.

[0052] The seal assembly 202 includes a seal structure 212 integrated with a turbine engine rotor 204 and a turbine engine static component 205. As noted above, in some forms, the seal structure 212 can be included with only one of the turbine engine rotor 204 and the turbine engine static component 205. Thus, one or more seal structures 212 can be located at an interface 207 between the turbine engine rotor 204 and the turbine engine static component 205, where it will be understood that the "interface" can include the coupling of the one or more seal structures 212 with either or both of the turbine engine rotor 204 and the turbine engine static component 205.

[0053] Turning now to Figure 3A and Figure 3B one embodiment of a seal structure 212 that can be included in the seal assembly 202 is shown. Figure 3A A side view of the seal structure 212 is shown extending in a circumferential direction C and having a thickness in a radial direction R. As will be understood, the circumferential direction C extends circumferentially about the annular shape of the turbine engine 100, while the radial direction R extends perpendicular to the axis of rotation 210 (shown in FIG. 1). The seal structure 212 includes a seal body 214 having a thickness extending in the radial direction between a first seal side 216 and a second seal side 218. Generally, the first seal side 216 of the seal structure 212 is coupled with either the turbine engine rotor 204 or the turbine engine static component 205, depending on any given application. Figure 2

[0054] The seal body 214 also includes a negative thermal expansion (NTE) layer 220 having an NTE base 222 extending in the radial direction between a first base side 224 and a second base side 226. The NTE base 222 can be integral with the seal body 214 (e.g., it can be a monolithic material that is cast or additively printed), or can be integrated with the seal body 214 by any suitable mechanism, including metallurgical bonding, chemical bonding, etc.

[0055] The NTE layer 220 includes an NTE reactive component 228 disposed in a channel 230 of the NTE base 222, the channel 230 defined between a first sidewall 232 and a second sidewall 234. The channel 230 can also include a sidewall bridge 240 extending between the first sidewall 232 and the second sidewall 234. Although the channel 230 is depicted as rectilinear in shape in the cross-sectional shape defined by the first sidewall 232, the second sidewall 234, and the sidewall bridge 240, other embodiments can include different cross-sectional shapes.

[0056] ​The NTE-reactive component 228 is composed of a material having a negative coefficient of thermal expansion such that the size of the NTE-reactive component 228 is inversely proportional to temperature. For example, as the temperature of the NTE-reactive component 228 increases from a first temperature to a second temperature, the NTE-reactive component 228 will decrease in size from a first size to a second size. The NTE-reactive component 228 can include a form of zirconium oxide. For example, the NTE-reactive component 228 can include a zirconium oxide alloy. The NTE-reactive component 228 can be partially stabilized zirconium oxide. In one non-limiting embodiment, the NTE-reactive component 228 can be ZrV207. In some forms, the NTE-reactive component 228 has a negative coefficient of thermal expansion of -10 microns / Kelvin. In additional and / or alternative forms, the negative coefficient of thermal expansion can be any negative coefficient of thermal expansion that is less than zero. For example, the negative coefficient of thermal expansion can be in a range of -7 microns / Kelvin to -11 microns / Kelvin.

[0057] Although Figure 3A and Figure 3B embodiments show a plurality of channels 230, it will be understood that in some forms a single channel 230 can be provided in the NTE layer 220.

[0058] Figure 3B A view of the seal structure 212 is shown in the radial direction R with channels 230 depicted as adjacent channels 230 that are axially separated relative to adjacent channels 230. The channels 230 extend in the circumferential direction, Figure 3B only a portion thereof is depicted in Figure 3B The channels 230 can take the form of a herringbone shape or a V-shape. In the illustrated embodiment, the channels 230 each include legs 236 that together form a segmented linear shape in the circumferential direction. The shape of the channels 230 as viewed in the radial direction (e.g., as shown in Figure 3B The shape of the channels 230 as viewed in the radial direction (e.g., as shown in

[0059] Figure 3A The embodiment of the NTE layer 220 depicted in Figure 3B is shown relative to a first temperature of the NTE-reactive component 228 and the NTE base 222. The NTE-reactive component 228 and the NTE base 222 are also shown in Figure 4A and Figure 4B at a second temperature that is higher than the first temperature in Figure 3A and Figure 3B The NTE-reactive component 228 and the NTE base 222 are also shown in Figure 3A and Figure 3B at the second temperature. The NTE-reactive component 228 and the NTE base 222 are shown in Figure 4A and Figure 4BThe temperature rise from the first temperature in Figure 3A and Figure 3B to the second temperature in Figure 4A and Figure 4B causes the NTE layer 220 to change shape, in particular, causes the NTE reactive component 228 to change shape.

[0060] When compared to the depiction in Figure 3A , Figure 4A illustrates the effect of the temperature rise of the NTE reactive component 228, where the NTE reactive component 228 experiences a reduction in the size of the NTE reactive component 228, in particular, a reduction in depth in the illustrated embodiment, as it relates to the radial depth of the channel 230. In one form, the NTE base 222 has a positive coefficient of thermal expansion, which contributes to a significant reduction in the depth of the NTE reactive component 228. The reduction in depth of the NTE reactive component 228 can form a fluid dynamic pocket 238 defined between the NTE reactive component 228 and the first and second side walls 232, 234 of the channel 230. The size of the fluid dynamic pocket 238 depends on the temperature of the NTE reactive component 228 and the NTE layer 220 at any given moment.

[0061] The formation of the fluid dynamic pocket 238 caused by the temperature rise resulting from the friction between the turbine engine rotor 204 and the turbine engine static component 205 can contribute to the generation of a local fluid dynamic lift force. The adjustment of the fluid dynamic lift force caused by the growth and / or formation of the fluid dynamic pocket 238 can be used to balance the rotor to a balanced position, thereby reducing and / or eliminating the friction between the turbine engine rotor 204 and the turbine engine static component 205. As used in relation to the fluid dynamic pocket, the term “growth” refers to an increase in the volume of the fluid dynamic pocket.

[0062] Turning now to Figure 5 and Figure 6 , the NTE layer 220 can take a different cross-sectional form than that depicted in Figure 3A and Figure 4A . Figure 3A and Figure 4A The embodiments of the channel 230 and the NTE reactive component 228 depicted in Figure 5 andFigure 6 The NTE reactive component 228 of FIG. 1 depicts the NTE reactive component 228 having a profile of a shape of a channel 230. This profile shape of the NTE reactive component 228 can result in a generally constant thickness of the NTE reactive component 228 along the first sidewall 232 and the second sidewall 234 and the sidewall bridge 240 between the first sidewall 232 and the second sidewall 234. In other forms, the profile can not be constant thickness, but still provide the fluid dynamic pocket 238.

[0063] The profile characteristics of the NTE reactive component 228 result in the formation of the fluid dynamic pocket 238 that can be defined by a groove 242. The groove 242 is defined by a first groove sidewall 244 of the NTE reactive component 228, a second groove sidewall 246 of the NTE reactive component 228, and a groove bridge 248 extending between the first groove sidewall 244 and the second groove sidewall 246. When the NTE reactive component 228 is reduced in size as shown in FIG. 1 due to an increase in temperature from a first temperature to a second temperature, the fluid dynamic pocket 238 can also be further defined by the first sidewall 232 and the second sidewall 234. Figure 6

[0064] Figure 5 The NTE layer 220 as shown in FIGS. 1-3 can include any of the axial and circumferential variations of the NTE layer 220 depicted in FIGS. 4-6 (e.g., a herringbone shape pattern repeated along a circumferential direction of the seal structure 212). Figure 6 The NTE layer 220 as shown in FIGS. 1-3 can include any of the axial and circumferential variations of the NTE layer 220 depicted in FIGS. 4-6 (e.g., a herringbone shape pattern repeated along a circumferential direction of the seal structure 212). Figure 3B The NTE layer 220 as shown in FIGS. 1-3 can include any of the axial and circumferential variations of the NTE layer 220 depicted in FIGS. 4-6 (e.g., a herringbone shape pattern repeated along a circumferential direction of the seal structure 212). Figure 4B The NTE layer 220 as shown in FIGS. 1-3 can include any of the axial and circumferential variations of the NTE layer 220 depicted in FIGS. 4-6 (e.g., a herringbone shape pattern repeated along a circumferential direction of the seal structure 212).

[0065] Figure 5 The embodiments of FIGS. 1-3 also depict the fluid dynamic pocket 238 that can be formed prior to the increase in temperature. Figure 6 The relative size of the fluid dynamic pocket 238 at the first temperature of the NTE reactive component 228 is depicted in FIG. 1, while the fluid dynamic pocket 238 at the second temperature of the NTE reactive component 228 is depicted in FIG. 2. Figure 5 The relative size of the fluid dynamic pocket 238 at the first temperature of the NTE reactive component 228 is depicted in FIG. 1, while the fluid dynamic pocket 238 at the second temperature of the NTE reactive component 228 is depicted in FIG. 2. Figure 6 The relative size of the fluid dynamic pocket 238 at the first temperature of the NTE reactive component 228 is depicted in FIG. 1, while the fluid dynamic pocket 238 at the second temperature of the NTE reactive component 228 is depicted in FIG. 2. Figure 5 The first temperature depicted in FIG. 1 can correspond to a standard day temperature similar to ambient temperature conditions prior to operating the turbine engine 100. Figure 6 The second temperature depicted in FIG. 2 can correspond to an operating temperature of the turbine engine 100. Further, Figure 6 The second temperature depicted in FIG. 2 can correspond to a temperature generated by friction of the turbine engine rotor 204 against the turbine engine static component 205. Due to the negative coefficient of thermal expansion of the NTE reactive component 228, Figure 5 The fluid dynamic pocket 238 shown at the first temperature in FIG. 1 is larger than the fluid dynamic pocket 238 shown at the second temperature in FIG. 2. Figure 6 ​The fluid dynamics bag 238 is shown at a higher second temperature. As the temperature of the NTE reactive component 228 increases from... Figure 5 The first temperature in the middle rises to Figure 6 At the second temperature, the size of the NTE reactive component 228 (e.g., the thickness measured relative to the first sidewall 232) decreases from the first size to the second size. As described above, the size of the fluid dynamics bag 238 depends on the temperature of the NTE reactive component 228 and the NTE layer 220 at any given time.

[0066] The growth of the hydrodynamic pocket 238 caused by the temperature rise due to friction between the turbine rotor 204 and the turbine static component 205 can help generate increased local hydrodynamic lift. Adjustment of the hydrodynamic lift caused by the growth of the hydrodynamic pocket 238 can be used to balance the rotor to an equilibrium position, thereby reducing and / or eliminating friction between the turbine rotor 204 and the turbine static component 205.

[0067] Now go to Figure 7 Another embodiment of the sealing structure 212 is depicted, which further includes a wear-resistant base layer 250 connecting the first sealing side 216 and the NTE layer 220. The wear-resistant base layer 250 may be made of a material that resists wear caused by contact with relatively moving parts. For example, if Figure 7 The sealing structure depicted is coupled to the turbine engine rotor 204, and the wear-resistant base layer 250 may include a material that resists wear when the sealing structure rubs against the turbine engine static component 205. The wear-resistant base layer 250 may be composed of materials such as chromium nitride or titanium nitride. In some embodiments, the wear-resistant base layer 250 may be integral with the NTE base 222. For example, the wear-resistant base layer 250 may be made of the same material as the NTE base 222 and may be formed simultaneously with the NTE base 222. In other embodiments, the wear-resistant base layer 250 may be integrated with the NTE base 222, such as through any suitable bonding operation (e.g., metallurgical bonding, chemical bonding, mechanical fastening, etc.). In some embodiments, the wear-resistant base layer 250 may serve as a bonding coating and manage thermal mismatch between the NTE layer 220 and the seal 214. Figure 7 The NTE layer 220 may include any variation of the NTE layer 220 discussed above, including those related to Figures 3A-6 Variations of the discussion.

[0068] What will be understood is... Figure 7 The sealing body 214 depicted may include, according to the above, the seal 214. Figures 3A-6 The channel 230 and NTE reactive component 228 formed in any of the depicted embodiments.

[0069] It is worth noting that,Figure 7 The embodiments also include a lattice compliant layer 252 disposed between the first seal 214a and the second seal 214b (collectively referred to as "seal 214"). In the illustrated embodiment, the radial thickness of the first seal 214a may be greater than the radial thickness of the second seal 214b. Other embodiments may include the first seal 214a and the second seal 214b having the same radial thickness, or may include a second seal 214b with a radial thickness greater than that of the first seal 214a.

[0070] The lattice compliance layer 252 extends radially between the first compliance layer side 262 and the second compliance layer side 264. The lattice compliance layer 252 is configured to provide additional structural compliance to the seal 214 relative to a monolithic seal 214 or seal 214 lacking the lattice compliance layer 252 in any other manner. When the turbine rotor 204 and the turbine stationary component 205 come into contact, the additional compliance present in the seal 214, including the lattice compliance layer 252, improves the durability and performance of the seal structure 212 by providing flexibility to the seal structure 212. This contact can be circumferential friction as described above, but can also include axial contact, such as that caused by thrust along the axial direction A during operation of the turbine engine 100. The lattice compliance layer 252 can provide axially related compliance. For example, in some forms, the lattice compliance layer 252 can provide axial compliance, radial compliance, and circumferential compliance that differ from each other. The lattice compliant layer 252 can be integrally formed with the first seal 214a and the second seal 214b, for example, by additive manufacturing.

[0071] Now go to Figure 8 And continue to refer to Figure 7 An embodiment of a lattice compliant layer 252 is shown. The lattice compliant layer 252 includes a plurality of lattice ligaments 254 that together define a plurality of cavities 256, such as... Figure 8 The straight lines depicted in the diagram. Lattice ligament 254 can be... Figure 8 The nodes 257 are depicted as points extending between each other. Although the lattice ligaments 254 and nodes 257 are depicted as lines and points, it will be understood that this depiction is for ease of reference and is not intended to imply that only these constructions exist. For example, the lattice ligaments 254 may exhibit curved and / or discontinuous shapes. Furthermore, a node 257 may simply be a combination between intersecting lattice ligaments 254, or a combination between an intersecting lattice ligament 254 and one or the other of the first compliant layer side 262 and the second compliant layer side 264, regardless of whether such combination forms a point shape as depicted.

[0072] Depending on the application, the lattice compliant layer 252, and especially the cavity 256, can be oriented in any particular direction. Figure 8The depiction in FIG. 26 shows cavities 256 bounded on the axial forward side and the axial aft side by adjacent, non-intersecting ligaments 254. The cavities 256 can also be bounded radially by the ligaments 254 located between the first lattice layer 258 and the second lattice layer 260 or by one or the other of the first compliant layer side 262 and the second compliant layer side 264. It will be appreciated that in the illustrated embodiment, the cavities 256 can extend in the circumferential direction. In other embodiments, the cavities 256 can be oriented to extend in the radial direction, while in further embodiments, the cavities 256 can be oriented to extend in the axial direction.

[0073] Figure 8 The cavities 256 depicted in FIG. 26 are arranged in the first lattice layer 258, radially offset from the second lattice layer 260. The first lattice layer 258 includes a plurality of cavities 256 defined by the ligaments 254 and the first compliant layer side 262 in a trapezoidal shape (e.g., trapezoidal shape), while the second lattice layer 260 includes a plurality of cavities 256 defined by the ligaments 254 and the second compliant layer side 264 in a triangular shape (e.g., triangular shape). The difference in the arrangement of the ligaments in the first lattice layer 258, and thus the shape of the cavities 256, compared to the arrangement of the ligaments in the second lattice layer 260 can provide a difference in compliance between the first lattice layer 258 and the second lattice layer 260. Accordingly, the compliance of the lattice compliant layer 252 can be tuned to provide a variable compliance over the thickness of the lattice compliant layer 252 between the first seal 214a and the second seal 214b. In one form, the compliance of the first lattice layer 258 is greater than the compliance of the second lattice layer 260 to provide greater deflection under loading of the first lattice layer 258.

[0074] Turning now to Figure 9 , a circumferential arrangement of a plurality of segments 266 of the seal structure 212 is depicted. Figure 8 The arrangement in FIG. 26 is viewed along the axial direction. In general, a total of twelve different segments 266 are depicted, with each segment 266 defining an arc 267 that extends in the circumferential direction. Accordingly, features within the seal structure 212 can also be defined by the arcs 267. For example, the cavities 256 can be arranged to extend circumferentially along the segments 266. When assembled together, the entire circumferential arc forms an annular shape.

[0075] Referring now to Figure 10 , an example method of operating a turbine engine seal is described. In some embodiments, the seal structure 212 can be coupled with either or both of the turbine engine rotor 204 and the turbine engine static component 205. As Figure 10As shown in FIG. 27, an example method 268 of operating a turbine engine seal can include, at step 270, operating a turbine engine 100 having a seal structure 212 at an interface 207 between a turbine engine rotor 204 and a turbine engine static component 205, the turbine engine seal structure 212 having an NTE layer 220 including an NTE reactive component 228. The NTE reactive component 228 can be located in a channel 230 formed in the NTE layer 220, where the channel 230 can extend circumferentially. The method of operating can include, at step 272, raising a temperature of the NTE layer 220 as a result of rubbing the turbine engine rotor 204 against the turbine engine static component 205. The rubbing can be a result of an unbalance condition of the turbine engine rotor 204 and / or a shift in an axis of rotation of the turbine engine rotor 204. At step 274, the method can also include reducing a size of the NTE reactive component 228 as the temperature of the seal structure 212 is raised. The method of operating can also include, at step 276, forming a fluid dynamic pocket 238 as the size of the NTE reactive component 228 is reduced. This formation of the fluid dynamic pocket 238 can be a creation of the fluid dynamic pocket 238 if the original configuration at a first temperature does not provide the fluid dynamic pocket 238, or a growth of the existing fluid dynamic pocket 238 if the original configuration at a second temperature already provides the fluid dynamic pocket 238. At step 278, the method can also include generating a fluid dynamic force from the fluid dynamic pocket 238 to resist contact of the turbine engine rotor 204 with the turbine engine static component 205. The forming of the fluid dynamic pocket 238 can include forming the fluid dynamic pocket to extend circumferentially along the NTE layer 220. The forming at step 272 can also include increasing a volume of the fluid dynamic pocket 238 from a first pocket size to a second pocket size as the temperature of the NTE layer is raised from a first temperature to a second temperature.

[0076] Referring now to Figure 11 , example methods of manufacturing a turbine engine seal are described. In some embodiments, one or more portions of the turbine engine seal can be manufactured using additive manufacturing techniques. Additionally or alternatively, one or more portions of the turbine engine seal can be manufactured using other techniques, such as casting, forging, machining, extruding, etc. As Figure 11As shown in FIG. 2, the exemplary method 280 of manufacturing a turbine engine seal can include, at block 282, printing, via additive manufacturing, a lattice compliant layer 252 of a seal structure 212 configured to be used at an interface 207 between a turbine engine rotor 204 and a turbine engine static component 205. At step 284, the method 280 further includes forming the lattice compliant layer 252 between a first seal side 216 of the seal body 214 and a second seal side 218 of the seal body 214 as a result of the printing. The lattice compliant layer 252 can have a structural compliance that varies with a thickness of the lattice compliant layer 252 between the first seal side 216 and the second seal side 218. The method 280 can further include, at step 286, coupling a negative thermal expansion (NTE) layer 220 to the second seal side 218 of the seal body 214. The NTE layer 220 can include an NTE reactive component 228 composed of a material having a negative coefficient of thermal expansion. The NTE reactive component 228 can decrease in size from a first size to a second size as a temperature increases from a first temperature to a second temperature. The method 280 can further include forming a plurality of ligaments 254 of the lattice compliant layer 252. The ligaments 254 can form a plurality of cavities 256 in combination with either of the first compliant layer side 262 and the second compliant layer side 264.

[0077] Further aspects of the presently disclosed subject matter are provided by the following clauses:

[0078] A turbine engine seal, comprising: a seal structure configured to be positioned between a turbine engine rotor and a turbine engine static component, the seal structure comprising: a seal body having a thickness extending in a radial direction between a first seal side and a second seal side; and a negative thermal expansion (NTE) layer disposed at the second seal side, the NTE layer configured to react to a change in temperature, the NTE layer comprising an NTE reactive component comprising a material having a negative coefficient of thermal expansion.

[0079] The turbine engine seal according to the preceding clause, wherein the NTE layer further comprises an NTE base extending in the radial direction between a first base side and a second base side, the NTE base comprising a material having a different coefficient of thermal expansion than the NTE reactive component, the NTE base having a channel, and wherein the NTE reactive component is disposed in the channel.

[0080] The turbine engine seal according to any of the preceding clauses, wherein the channel of the NTE base comprises a plurality of channels, wherein the NTE reactive component comprises a plurality of NTE reactive components, and wherein each channel of the plurality of channels comprises a respective NTE reactive component of the plurality of NTE reactive components, and wherein the plurality of channels are dispersed circumferentially along the arc of the NTE base.

[0081] The turbine engine seal according to any of the preceding clauses, wherein the channel extends in a segmented linear configuration along the arc of the NTE base.

[0082] The turbine engine seal according to any of the preceding clauses, wherein the channel extends in a repeating herringbone shape along the arc of the NTE base.

[0083] The turbine engine seal according to any of the preceding clauses, wherein the channel comprises a first sidewall and a second sidewall, the first sidewall being opposite the second sidewall.

[0084] The turbine engine seal according to any of the preceding clauses, wherein during operation of the seal structure, an increase in temperature of the NTE reactive component causes a decrease in size of the NTE reactive component from a first size to a second size, wherein the decrease in size of the NTE reactive component increases a size of a fluid dynamics pocket formed between the first sidewall and the second sidewall.

[0085] The turbine engine seal according to any of the preceding clauses, wherein the NTE layer defines a groove having a first groove sidewall and a second groove sidewall, and wherein a fluid dynamics pocket is formed between the first groove sidewall and the second groove sidewall.

[0086] The turbine engine seal according to any of the preceding clauses, wherein the fluid dynamics pocket extends circumferentially along the arc of the NTE base.

[0087] The turbine engine seal according to any of the preceding clauses, wherein the fluid dynamics pocket extends circumferentially in a herringbone shape.

[0088] The turbine engine seal according to any of the preceding clauses, further comprising a wear resistant base layer coupled between the first seal side and the NTE layer.

[0089] A rotary machine comprising: a turbine engine rotor of a turbine engine having a negative thermal expansion (NTE) layer configured to undergo a dimensional reaction upon the NTE layer experiencing a temperature increase from a first temperature to a second temperature, the NTE layer defining at least a portion of a fluid dynamics pocket formed at the second temperature of the NTE layer.

[0090] The rotary machine according to any of the preceding clauses, wherein the NTE layer further comprises an NTE base having a thickness extending in a radial direction between a first base side and a second base side, the NTE base having a channel, and wherein the channel extends partially into the thickness of the NTE layer.

[0091] The rotary machine according to any of the preceding clauses, wherein the channel comprises a first sidewall, a second sidewall, and a sidewall bridge extending between the first sidewall and the second sidewall, wherein the first sidewall is positioned opposite the second sidewall, and wherein an NTE reactive component is disposed in the channel.

[0092] The rotary machine according to any of the preceding clauses, wherein the NTE reactive component is profiled along the first sidewall, the second sidewall, and the sidewall bridge.

[0093] The rotary machine according to any of the preceding clauses, wherein the NTE reactive component is disposed as a constant thickness along each of the first sidewall, the second sidewall, and the sidewall bridge.

[0094] The rotary machine according to any of the preceding clauses, wherein the seal further comprises a lattice compliant layer disposed within the seal between a first seal side and a second seal side.

[0095] The rotary machine according to any of the preceding clauses, wherein the lattice compliant layer comprises a plurality of lattice ligaments each extending between adjacent nodes of a plurality of nodes.

[0096] The rotary machine according to any of the preceding clauses, wherein the lattice compliant layer comprises a plurality of cavities defined by the plurality of lattice ligaments.

[0097] The rotary machine according to any of the preceding clauses, wherein the plurality of cavities comprises a first lattice layer and a second lattice layer, the first lattice layer positioned radially offset from the second lattice layer.

[0098] The rotary machine according to any of the preceding clauses, wherein the first lattice layer comprises a plurality of cavities having a trapezoidal shape.

[0099] The rotating machine according to any of the preceding clauses, wherein the first lattice layer includes a plurality of cavities having a triangular shape.

[0100] The rotating machine according to any of the preceding clauses, wherein the lattice compliant layer has a first compliance along an axial direction at the first seal body side of the seal body and a second compliance along the axial direction at the second seal body side of the seal body.

[0101] The rotating machine according to any of the preceding clauses, wherein the seal body includes a plurality of layers including the lattice compliant layer.

[0102] The rotating machine according to any of the preceding clauses, the plurality of layers including a first seal body and a second seal body, wherein the lattice compliant layer is positioned between the first seal body and the second seal body.

[0103] The rotating machine according to any of the preceding clauses, wherein a radial thickness of the first seal body is greater than a radial thickness of the second seal body.

[0104] The rotating machine according to any of the preceding clauses, wherein the lattice compliant layer is a unitary component including an overall structure between a first compliant layer side and a second compliant layer side.

[0105] The rotating machine according to any of the preceding clauses, further comprising a wear base layer coupled to the second seal body side of the seal body, wherein the wear base layer has a thickness extending in the radial direction from a first wear side coupled to the second seal body side of the seal body to a second wear side, and wherein the second wear side includes a plurality of channels extending partially into the thickness of the wear base layer.

[0106] The rotating machine according to any of the preceding clauses, wherein the plurality of channels each include a first channel sidewall and a second channel sidewall, the first channel sidewall opposite the second channel sidewall, and further comprising a negative thermal expansion (NTE) reactive component disposed in the plurality of channels and secured to each of the first channel sidewall and the second channel sidewall.

[0107] The rotating machine according to any of the preceding clauses, wherein the NTE reactive component is composed of a material having a negative coefficient of thermal expansion.

[0108] The rotating machine according to any of the preceding clauses, wherein the NTE reactive component defines a groove having a first groove sidewall and a second groove sidewall, and wherein a fluid dynamics pocket is formed between the first groove sidewall and the second groove sidewall.

[0109] The rotating machine according to any of the preceding clauses, wherein the fluid dynamics pocket extends circumferentially along an arc of the wear-resistant base layer.

[0110] The rotating machine according to any of the preceding clauses, wherein the fluid dynamics pocket extends circumferentially in a chevron shape.

[0111] A method of operating a turbine engine seal, comprising: operating a turbine engine having a seal structure at an interface between a turbine engine rotor and a turbine engine static component, the seal structure having a negative thermal expansion (NTE) layer, the NTE layer comprising an NTE reactive component; increasing a temperature of the NTE layer from a first temperature to a second temperature due to friction of the turbine engine rotor against the turbine engine static component; decreasing a size of the NTE reactive component as the temperature of the seal structure increases; forming a fluid dynamics pocket as the NTE reactive component decreases the size; and generating a fluid dynamic force from the fluid dynamics pocket to resist contact of the turbine engine rotor with the turbine engine static component.

[0112] The method according to the preceding clause, wherein forming the fluid dynamics pocket further comprises forming the fluid dynamics pocket extending circumferentially along the NTE layer.

[0113] The method according to any of the preceding clauses, wherein the NTE reactive component comprises a plurality of NTE reactive components.

[0114] The method according to any of the preceding clauses, wherein the forming further comprises increasing a volume of the fluid dynamics pocket from a first pocket size to a second pocket size as the NTE layer increases from the first temperature to the second temperature.

[0115] This written description uses examples to describe the presently disclosed subject matter, including the best mode, and also to enable any person skilled in the art to practice the subject matter, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the presently disclosed subject matter is defined by the claims, and can include other examples that occur to those skilled in the art. Such other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

1. A turbine engine seal, characterized in that, include: A sealing structure configured to be positioned between a turbine engine rotor and static components of the turbine engine, the sealing structure comprising: A sealing body having a thickness extending in the radial direction between a first sealing side and a second sealing side; as well as A negative thermal expansion (NTE) layer is disposed on the second sealing side. The NTE layer is configured to respond to temperature changes and includes NTE reactive components comprising a material having a negative coefficient of thermal expansion.

2. The turbine engine seal according to claim 1, characterized in that, The NTE layer further includes an NTE base extending in the radial direction between a first base side and a second base side, the NTE base comprising a material having a different coefficient of thermal expansion than the NTE reactive component, the NTE base having channels in which the NTE reactive component is disposed.

3. The turbine engine seal according to claim 2, characterized in that, in, The channel of the NTE base includes a plurality of channels, wherein the NTE reactive component includes a plurality of NTE reactive components, and wherein each of the plurality of channels includes a corresponding NTE reactive component among the plurality of NTE reactive components, and wherein the plurality of channels are circumferentially dispersed along the NTE base.

4. The turbine engine seal according to claim 2, characterized in that, in, The channel extends along the arc of the NTE base in a piecewise linear configuration.

5. The turbine engine seal according to claim 2, characterized in that, in, The channel extends along the arc of the NTE base in a repeating herringbone shape.

6. The turbine engine seal according to claim 2, characterized in that, in, The channel includes a first sidewall and a second sidewall, with the first sidewall and the second sidewall facing each other.

7. The turbine engine seal according to claim 6, characterized in that, in, During operation of the sealing structure, the temperature rise of the NTE reactive component causes the size of the NTE reactive component to decrease from a first size to a second size, wherein the decrease in size of the NTE reactive component increases the size of the fluid dynamics bag formed between the first sidewall and the second sidewall.

8. The turbine engine seal according to claim 1, characterized in that, in, The NTE layer defines a groove having a first groove sidewall and a second groove sidewall, wherein a fluid dynamics bag is formed between the first groove sidewall and the second groove sidewall.

9. The turbine engine seal according to claim 8, characterized in that, in, The fluid dynamics bag extends circumferentially along the base of the NTE.

10. The turbine engine seal according to claim 8, characterized in that, in, The fluid dynamics bag extends circumferentially in a herringbone shape.

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