Patent Application
20120128472
The subject matter disclosed herein relates to the art of turbomachines and, more particularly, to a turbomachine nozzle segment having an integrated diaphragm.
In general, gas turbomachines combust a fuel/air mixture that releases heat energy to form a high temperature gas stream. The high temperature gas stream is channeled to a turbine section via a hot gas path. In the turbine, the high temperature gas stream passes through a plurality of stages. Each stage includes a plurality of nozzles arranged upstream from a plurality of turbine blades. The high temperature gas stream passes over the nozzles, then acts upon or rotates the turbine blades. The plurality of nozzles are mounted to a housing of the turbine section and a diaphragm is mounted to each of the plurality of nozzles. A discourager seal is provided at an interface between each of the plurality of nozzles and the associated diaphragm. The discourager seals on each of the plurality of nozzles interact one with the other to reduce loss of the high temperature gases or working fluid from the corresponding one of the plurality of stages of the turbine section. The turbine blades convert thermal energy from the high temperature gas stream to mechanical energy that rotates a turbine shaft. The turbine may be used in a variety of applications such as providing power to a pump or an electrical generator.
According to one aspect of the invention, a turbomachine nozzle segment includes a vane having a first end extending to a second end through an airfoil portion. An outer member is positioned at the first end of the vane. The outer member includes a mounting element configured and disposed to secure the turbomachine nozzle segment to a turbomachine. An inner member is positioned at the second end of the vane. The inner member includes an upstream section and a downstream section. An upstream diaphragm member extends substantially radially outwardly from the inner member at the upstream section, and a downstream diaphragm member extends substantially radially outwardly from the inner member at the downstream section. Each of the upstream diaphragm member and down stream member includes an outer surface and an inner surface. One of the outer surface and inner surface of each of the upstream diaphragm member and downstream diaphragm member includes a cartridge mounting member.
According to another aspect of the invention, a turbomachine nozzle cartridge includes a main body having an outer surface and an inner surface that extend between an upstream end and a downstream end. The nozzle cartridge is configured and disposed to be mounted between an upstream diaphragm member and a downstream diaphragm member of a turbomachine nozzle.
According to yet another aspect of the invention, a turbomachine includes a compressor section, a turbine section operatively connected to the compressor section, and a turbine nozzle positioned within the turbine section. The turbine nozzle includes a vane having a first end extending to a second end through an airfoil portion. An outer member is positioned at the first end of the vane. The outer member includes a mounting element configured and disposed to secure the turbomachine nozzle to a turbomachine. An inner member is positioned at the second end of the vane. The inner member includes an upstream section and a downstream section. An upstream diaphragm member extends substantially radially outwardly from the inner member at the upstream section, and a downstream diaphragm member extends substantially radially outwardly from the inner member at the downstream section. Each of the upstream diaphragm member and down stream member includes an outer surface and an inner surface. One of the outer surface and inner surface of each of the upstream diaphragm member and downstream diaphragm member includes a cartridge mounting member. A cooling passage extends from the outer member through the airfoil portion to the inner member. A nozzle cartridge includes a main body having an outer surface and an inner surface that extend between an upstream end and a downstream end. The nozzle cartridge is mounted between the upstream diaphragm member and the downstream diaphragm member of a turbomachine nozzle.
These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
Referring to
Reference will now be made to
Nozzle segment 30 also includes an inner member 60 integrally formed at second end 35 of airfoils 18, 18a, and 18b. Inner member 60 includes a main body 64 having an upstream section 67 and a downstream section 69. Main body 64 also includes a first circumferential edge 72 and a second, opposing, circumferential edge 73 that establish a circumferential profile 75 for inner member 60. In a manner similar to that described above, in the exemplary embodiment shown, circumferential profile 75 is about 22.5° of an overall circumference of second stage 17. Each circumferential edge 72 and 73 includes a corresponding angled or dogleg section 79 and 80. Each circumferential edge 72 and 73 is also provided with a seal slot or groove 81 and 82 respectively. At this point it should be understood that the term “inner” refers to a portion of nozzle segment 30 that is positioned near a centerline of turbomachine 2. The term “outer” refers to a portion of nozzle segment 30 that is positioned away from the centerline in a direction of a casing of turbomachines 2.
In accordance with the exemplary embodiment, inner member 60 includes an upstream diaphragm member 84 and a downstream diaphragm member 86. Upstream diaphragm member 84 is integrally formed with inner member 60 and extends generally radially outwardly from upstream section 67 between first and second circumferential edges 72 and 73. Similarly, downstream diaphragm member 86 is integrally formed with inner member 60 and extends generally radially outwardly from downstream section 69 between first and second circumferential edges 72 and 73. Upstream diaphragm member 84 includes a first end 90 that extends from upstream section 67 to a second end 91. Second end 91 includes a generally curvilinear circumferential profile (not separately labeled). Upstream diaphragm member 84 also includes an outer surface 93 and an inner surface 94 (
Upstream diaphragm member 84 and downstream diaphragm member 86 are also shown to include discourager seals 104 and 105 provided on outer surfaces 93 and 100 respectively. Discourager seals 104 and 105 can either be integrally formed on corresponding ones of outer surfaces 93 and 100 or may be mounted in grooves or other structure (not shown) provided on corresponding ones of outer surfaces 93 and 100. In addition, upstream diaphragm member 84 and downstream diaphragm member 86 are also shown to include cartridge mounting members 110 and 112 provided on corresponding ones of inner surfaces 94 and 101. As will be discussed more fully below, cartridge mounting members 110 and 112 provide an interface for additional sealing structure for nozzle segment 30. Nozzle segment 30 is also shown to include a plurality of passages 118-120 that deliver cooling fluid flow, in the form of compressor discharge air, through airfoils 18, 18a, and 18b respectively. Passages 118-120 lead though airfoils 18, 18a, and 18b into a region 121 that extends between upstream diaphragm member 84 and downstream diaphragm member 86. Region 121 receives extraction air through a plurality of cooling passages 118-120 that extend through airfoils 18, 18a, and 18b, and is pushed out through openings 122-124 that are formed in upstream diaphragm member 84. At this point it should be understood that various other cooling scheme, including the use of cooling tubes or conduits that extend from upstream diaphragm member 84, through airfoils 18, 18a, and 18b, and to a casing of turbomachine 2 could also be employed
In further accordance with the exemplary embodiment, nozzle segment 30 includes a nozzle cartridge 136 (
As best shown in
Reference will now be made to
An upstream diaphragm member 205 is integrally formed with inner member 190 and extends generally radially outwardly from upstream section 195. Similarly, a downstream diaphragm member 207 is also integrally formed with inner member 190 and extends generally radially outwardly from downstream section. Upstream diaphragm member 205 includes a first end 211 that extends from upstream section 195 to a second end 212. Second end 212 includes a generally curvilinear circumferential profile (not shown). Upstream diaphragm member 205 also includes an outer surface 214 and an inner surface 215 that extend between first and second ends 211 and 212. Similarly, downstream diaphragm member 207 includes a first end 219 that extends from downstream section 196 to a second end 220. Second end 220 includes a generally curvilinear circumferential profile (not shown). Downstream diaphragm member 207 also includes an outer surface 222 and an inner surface 223 that extend between first and second ends 219 and 220. A first discourager seal 225 is provided on outer surface 214 of upstream diaphragm member 205 and a second discourager seal 226 is provided on outer surface 222 of downstream diaphragm member 207. Inner member 190 is also shown to include a first cartridge mounting member 228 that is provided on outer surface 214 of upstream diaphragm member 205 and a second cartridge mounting member 230 provided on outer surface 222 of downstream diaphragm member 207.
In further accordance with the exemplary aspect depicted in
At this point it should be appreciated that the exemplary embodiments provide a nozzle segment having an integrated diaphragm that reduces leakage points and simplifies construction by reducing or even eliminating numerous welded joints. In addition the particular construction of the nozzle segment eliminates load sharing with adjacent nozzle segments. The integrated diaphragm eliminates numerous diaphragm machining operations saving time/labor/costs associated with forming and installing nozzles in a turbomachine. The exemplary embodiments are further shown to reduce both known and unknown leakages thereby enhancing turbomachine efficiency. Finally, it should be understood that the particular nozzle segment shown is exemplary, the number of vanes as well as the materials used may vary.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
