The subject matter disclosed herein relates to turbomachines. More particularly, the subject matter disclosed herein relates to an inner rib profile for turbine blades.
Some jet aircraft and simple or combined cycle power plant systems employ a gas turbine engine, or a so-called turbomachine, in their configuration and operation. Some of the gas turbine engines employ expansion turbines having one or more stages of turbine blades, which during operation are exposed to fluid flows at high temperatures and pressures. The turbine blades include airfoils configured to aerodynamically interact with the fluid flows and to generate energy from these fluid flows as part of power generation. For example, the airfoils may be used to create thrust, to convert kinetic energy to mechanical energy, and/or to convert thermal energy to mechanical energy. The fluid flow may include hot combustion gases, requiring internal cooling of the airfoil of the turbine blade. Cooling may be provided using, for example, channels defined by various ribs within an internal coolant passage. As a result of the physical and thermal interactions, the structures of the airfoils (e.g., the ribs within the internal coolant passage) are exposed to a variety of stresses that can negatively impact the lifespan of the turbine blades.
All aspects, examples and features mentioned below can be combined in any technically possible way.
An aspect of the disclosure includes a turbine blade comprising: an airfoil having: a suction side, a pressure side opposing the suction side, a leading edge, a trailing edge, and a first rib separating a portion of an internal space defined between the suction and pressure sides and the leading and trailing edges into at least two internal channels; and a platform connected with the airfoil along the suction and pressure sides and the leading and trailing edges, the airfoil and the platform including an origin at a junction of the leading edge of the airfoil and the platform; wherein a portion of the first rib has a shape having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in TABLE I, wherein the Cartesian coordinate values are non-dimensional values of from 0% to 100% convertible to distances from the origin by multiplying the values by a height of the airfoil expressed in units of distance, and wherein the Cartesian coordinate values of X, Y, and Z are connected by smooth continuing arcs to define the nominal profile of the portion of the first rib.
Another aspect of the disclosure includes any of the preceding aspects, and the turbine blade includes a first stage blade.
Another aspect of the disclosure includes any of the preceding aspects, and further comprising a fillet connecting a surface of the platform to the airfoil.
Another aspect of the disclosure includes any of the preceding aspects, and the portion of the first rib includes a radially outer portion of the first rib positioned radially inward of a radial outer end of the at least two internal channels.
Another aspect of the disclosure includes any of the preceding aspects, and the first rib extends from a second rib to a third rib adjacent an inner surface of a pressure sidewall of the airfoil, wherein the second rib and the third rib further separate the portion of the internal space into the at least two internal channels.
Another aspect of the disclosure includes a rotor blade section for a turbine, the rotor blade section comprising: a set of rotating blades, the set of rotating blades including at least one blade having: an airfoil having: a suction side, a pressure side opposing the suction side, a leading edge, a trailing edge, and a first rib within an internal space defined between the suction and pressure sides and the leading and trailing edges, the first rib separating the internal space into at least two internal channels; and a platform connected with the airfoil along the suction and pressure sides and the leading and trailing edges, the airfoil and the platform including an origin at a junction of the leading edge of the airfoil and the platform; wherein a portion of the first rib has a shape having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in TABLE I, wherein the Cartesian coordinate values are non-dimensional values of from 0% to 100% convertible to distances from the origin by multiplying the values by a height of the airfoil expressed in units of distance, and wherein the Cartesian coordinate values of X, Y and Z are connected by smooth continuing arcs to define the nominal profile of the portion of the first rib.
Another aspect of the disclosure includes any of the preceding aspects, and further comprising a fillet connecting a surface of the platform to the airfoil.
Another aspect of the disclosure includes any of the preceding aspects, and the rotor blade section is a first stage blade section.
Another aspect of the disclosure includes any of the preceding aspects, and the portion of the first rib includes a radially outer portion of the first rib positioned radially inward of a radial outer end of the at least two internal channels.
Another aspect of the disclosure includes any of the preceding aspects, and the first rib extends from a second rib to a third rib adjacent an inner surface of a pressure sidewall of the airfoil, wherein the second rib and the third rib further separate the portion of the internal space into the at least two internal channels.
Another aspect of the disclosure includes a turbine comprising a plurality of turbine blades in a rotor blade section, at least one of the plurality of turbine blades comprising: an airfoil having: a suction side, a pressure side opposing the suction side, a leading edge, a trailing edge, and a first rib separating a portion of an internal space defined between the suction and pressure sides and the leading and trailing edges into at least two internal channels; and a platform connected with the airfoil along the suction and pressure sides and the leading and trailing edges, the airfoil and the platform including an origin at a junction of the leading edge of the airfoil and the platform; wherein a portion of the first rib has a shape having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in TABLE I, wherein the Cartesian coordinate values are non-dimensional values of from 0% to 100% convertible to distances from the origin by multiplying the values by a height of the airfoil expressed in units of distance, and wherein the Cartesian coordinate values of X, Y and Z are connected by smooth continuing arcs to define the nominal profile of the portion of the first rib.
Another aspect of the disclosure includes any of the preceding aspects, and further comprising a fillet connecting a surface of the platform to the airfoil.
Another aspect of the disclosure includes any of the preceding aspects, and each turbine blade includes a first stage blade.
Another aspect of the disclosure includes any of the preceding aspects, and the portion of the first rib includes a radially outer portion of the first rib positioned radially inward of a radial outer end of the at least two internal channels.
Another aspect of the disclosure includes any of the preceding aspects, and the first rib extends from a second rib to a third rib adjacent an inner surface of a pressure sidewall of the airfoil, wherein the second rib and the third rib further separate the portion of the internal space into the at least two internal channels.
Two or more aspects described in this summary section may be combined to form implementations not specifically described herein.
The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects and advantages will be apparent from the description and drawings, and from the claims.
These and other features of this disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure taken in conjunction with the accompanying drawings that depict various embodiments of the disclosure, in which:
It is noted that the drawings of the disclosure are not necessarily to scale. The drawings are intended to depict only typical aspects of the disclosure and therefore should not be considered as limiting the scope of the disclosure. In the drawings, like numbering represents like elements between the drawings.
As an initial matter, in order to clearly describe the current technology, it will become necessary to select certain terminology when referring to and describing relevant machine components within a turbomachine. To the extent possible, common industry terminology will be used and employed in a manner consistent with its accepted meaning. Unless otherwise stated, such terminology should be given a broad interpretation consistent with the context of the present application and the scope of the appended claims. Those of ordinary skill in the art will appreciate that often a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single part may include and be referenced in another context as consisting of multiple components. Alternatively, what may be described herein as including multiple components may be referred to elsewhere as a single part.
In addition, several descriptive terms may be used regularly herein, and it should prove helpful to define these terms at the onset of this section. These terms and their definitions, unless stated otherwise, are as follows. As used herein, “downstream” and “upstream” are terms that indicate a direction relative to the flow of a fluid, such as the working fluid through the turbine engine or, for example, the flow of air through the combustor or coolant through one of the turbine's component systems. The term “downstream” corresponds to the direction of flow of the fluid, and the term “upstream” refers to the direction opposite to the flow. The terms “forward” and “aft,” without any further specificity, refer to directions, with “forward” referring to the front or compressor end of the engine, and “aft” referring to the rearward or turbine end of the engine.
It is often required to describe parts that are disposed at different radial positions with regard to a center axis. The term “radial” refers to movement or position perpendicular to an axis. For example, if a first component resides closer to the axis than a second component, it will be stated herein that the first component is “radially inward” or “inboard” of the second component. If, on the other hand, the first component resides further from the axis than the second component, it may be stated herein that the first component is “radially outward” or “outboard” of the second component. The term “axial” refers to movement or position parallel to an axis. Finally, the term “circumferential” refers to movement or position around an axis. It will be appreciated that such terms may be applied in relation to the center axis of the turbomachine.
In addition, several descriptive terms may be used regularly herein, as described below. The terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. “Optional” or “optionally” means that the subsequently described feature or element may or may not be present and that the description includes instances where the feature is present and instances where it is not.
Where an element or layer is referred to as being “on,” “engaged to,” “connected to” or “coupled to” another element or layer, it may be directly on, engaged to, connected to, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to” or “directly coupled to” another element or layer, no intervening elements or layers are present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
As noted herein, various aspects of the disclosure are directed toward turbine blades that rotate (hereinafter, “blade” or “turbine blade”). A turbine blade may include an airfoil having: a suction side, a pressure side opposing the suction side, a leading edge and a trailing edge. The airfoil may also include a rib separating a portion of an internal space defined between the suction and pressure sides and the leading and trailing edges into at least two internal channels. The turbine blade may also include a platform connected with the airfoil along the suction and pressure sides and the leading and trailing edges, i.e., as part of a root of the turbine blade. The airfoil and the platform include an origin at a junction of the leading edge of the airfoil and the platform. A portion of the rib has a shape having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in TABLE I. The Cartesian coordinate values are non-dimensional values of from 0% to 100% convertible to distances from the origin by multiplying the values by a height of the airfoil expressed in units of distance. The X and Y values connected by smooth continuing arcs define rib profile sections at each distance Z along the portion of the rib. The profile sections at the Z distances are joined smoothly with one another to form the nominal profile. The portion of the rib defined by the profile herein is positioned between two other ribs adjacent an inner surface of a pressure sidewall of the airfoil, at or slightly aft of the area of maximum thickness of the airfoil. The other two ribs further separate the portion of the internal space into the at least two internal channels. The rib provides discrete regions of varying thickness and optimized filleting to reduce stress near turns between channels on either side of the rib. More particularly, the rib includes a complex fillet shape along a turn thereof that separates two internal channels.
Referring to the drawings,
In one non-limiting embodiment, GT system 100 is a 7HA.03 engine, commercially available from GE Vernova, Cambridge, MA, USA. The present disclosure is not limited to any one particular GT system 100 and may be implanted in connection with other engines including, for example, the other HA, F, B, LM, GT, TM and E-class engine models of GE Vernova, and engine models of other companies. Further, the teachings of the disclosure are not necessarily applicable to only a GT system and may be applied to other types of turbomachines, e.g., steam turbines, jet engines, compressors, etc.
A set of stationary vanes or nozzles 112 cooperate with a set of rotating blades 114 to form each stage S0-S3 of turbine 108 and to define a portion of a flow path through turbine 108. Rotating blades 114 in each set are coupled to a respective rotor wheel 116 that couples them circumferentially to rotor shaft 110 (
In operation, air flows through compressor 102, and compressed air is supplied to combustor 104. Specifically, the compressed air is supplied to fuel nozzle assembly 106 that is integral to combustor 104. Fuel nozzle assembly 106 is in flow communication with combustion region 105. Fuel nozzle assembly 106 is also in flow communication with a fuel source (not shown in
With reference to
As shown, blade 200 can also include a platform 212 connected at a radial inner end 250 of airfoil 202 and a tip end 252 on an opposite end of airfoil 202. In
With reference again to
With reference to
As shown in
In the example shown, (first) rib 260 extends from a (second) rib 290 to a (third) rib 292 adjacent an inner surface 296 of pressure sidewall 298 of airfoil 202, and near-wall channels 268 are disposed along pressure side 206. The near-wall channel 268 bounded by (first) rib 260 is disposed at or slightly aft of the area of maximum thickness of airfoil 202. Rib 290 and rib 292 further separate (or help to separate) the portion of internal space 262 into other internal channel(s), e.g., 294. For example, rib 260 with rib portion 280 may have a terminal edge in contact with second rib 290 that partially defines central channel 294 and an opposite terminal edge in contact with third rib 292 that partially defines one of the near-wall cooling channels 268 along pressure side 206.
The nominal shape of rib portion 280 is configured to reduce stresses experienced by rib 260 and increase a lifespan of turbine blade 200 (
The Cartesian coordinate values are expressed in normalized or non-dimensionalized form in values of from 0% to 100% (percentages), but it should be apparent that any or all of the coordinate values could instead be expressed in distance units so long as the percentages and proportions are maintained. To convert an X, Y or Z value of TABLE I to a respective X, Y or Z coordinate value in units of distance, such as inches or centimeters, the non-dimensional X, Y or Z value given in TABLE I can be multiplied by an airfoil height H of airfoil 202 in such units of distance. “Airfoil height” H is defined as a radial distance from origin 220 to a location of tip 252 thereover. Representative heights of airfoil 202 may range from about 5.0 inches (˜12.7 centimeters (cm)) to about 12.0 inches (˜30.48 cm). In a particular embodiment of an S0 blade for a GE Vernova 7HA.03 heavy-duty gas turbine engine, the height H of airfoil 202 may be about 7.89 inches (˜20.04 cm).
By connecting the X, Y, and Z data points smoothly with one another (with lines and/or arcs), a surface profile for rib portion 280 may be formed using any now known or later developed curve fitting technique to generate a curved surface appropriate for, for example, an airfoil. Curve fitting techniques may include but are not limited to: extrapolation, interpolation, smoothing, polynomial regression, and/or other mathematical curve fitting functions. The curve fitting technique may be performed manually and/or computationally, e.g., through statistical and/or numerical-analysis software.
The values in TABLE I are non-dimensionalized percentages generated and shown to three decimal places for determining the nominal profile of rib portion 280 at ambient, non-operating, or non-hot conditions, and do not take any coatings or fillets into account, though embodiments could account for other conditions, coatings, and/or fillets. To allow for typical manufacturing tolerances and/or coating thicknesses, ±values can be added to the values listed in TABLE I, particularly to the X and Y values therein. For example, a tolerance of about 10-20 percent of a minimum thickness of rib portion 280 in a direction normal to any surface location along rib portion 280 can define rib portion 280 profile envelope for rib portion design at cold or room temperature. In other words, a distance of about 10-20 percent of a minimum thickness of rib portion 280 in a direction normal to any surface location thereof can define a range of variation between measured points on an actual rib portion 280 and ideal positions of those points, particularly at a cold or room temperature, as embodied by the disclosure. The rib portion 280 configuration, as embodied herein, is robust to this range of variation without impairment of mechanical and aerodynamic functions.
Likewise, the profile and/or configuration can be scaled up or down, such as geometrically, without impairment of operation. Such scaling can be facilitated by multiplying the normalized/non-dimensionalized percentage values by a common scaling factor, which may be a larger or smaller number of distance units than might have originally been used for rib 272 of a given height airfoil 202. For example, the non-dimensionalized percentage values in TABLE I, particularly the X and Y values, could be multiplied uniformly by a scaling factor of 2, 0.5, or any other desired scaling factor. In various embodiments, the X, Y, and Z distances are scalable as a function of the same constant or number to provide a scaled up or scaled down rib portion 280. Alternatively, the values could be multiplied by a larger or smaller desired airfoil height H. As referenced herein, origin 220 of the X, Y, Z coordinate system is the leading edge junction of airfoil 202 with surface 224 of platform 212.
Where a Z value is used that is not expressly listed in TABLE I, the corresponding X and Y values can be identified through extrapolation. For example, if a Z layer is required at 87%, then the X value at 80% plus 0.7 times (70% of) the difference between the X value at 80% and 90%, can be used. Similarly, the Y value at 80% plus 0.7 times (70% of) the difference between the Y value at 80% and 90%, can be used. Other extrapolation processes can also be employed.
The disclosed shape of rib portion 280 provides a unique profile to achieve optimized stress relief at rib 260 to meet performance targets specific to the machine in which rotating blade 200 used, and perhaps other machines.
Embodiments of the disclosure also include a rotor blade section for a turbine, e.g., a stage, including a set of rotating blades 200 including at least one blade 200 having rib 260 with rib portion 280 as described herein.
Embodiments of the disclosure also include turbine 108 including a plurality of turbine blades 200, as described herein.
Embodiments of the disclosure provide various technical and commercial advantages, examples of which are discussed herein. The rib described herein provides discrete regions of varying thickness and optimized filleting to reduce stress near turns between channels on either side of the rib. More particularly, the rib includes a complex fillet shape along a turn thereof that separates two internal channels that reduces stress in the airfoil and increases the lifespan of the turbine blade, rotor blade section and/or turbine in which used.
While the apparatus and devices of the present disclosure are contemplated for use in a heavy-duty turbomachine deployed in a power generation system, rib 260 of the present disclosure may be also used for turbine blades 200 for other systems not described herein that may benefit from the increased stress relief associated with the improved profile of rib portion 280.
Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “approximately” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged; such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. “Approximately” as applied to a particular value of a range applies to both end values and, unless otherwise dependent on the precision of the instrument measuring the value, may indicate +/−10% of the stated value(s).
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present disclosure has been presented for purposes of illustration and description but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The embodiment was chosen and described in order to best explain the principles of the disclosure and its practical application and to enable others of ordinary skill in the art to understand the disclosure such that various modifications as are suited to a particular use may be further contemplated.
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