Abstract:
Embodiments of the present invention provide a system for regulating a cooling fluid within a turbomachine. The system may include a plurality of bypass chambers, wherein each of the plurality of bypass chambers allows for the cooling fluid to pass from the compressor section to a wheelspace area. The system includes a plurality of angular passages that aid in the mixing of a cooling fluid with a working fluid in the wheelspace area.

Description:
[0001]    This is a continuation-in-part application claiming priority to commonly-assigned U.S. patent application Ser. No. 11/799,162 [GE Docket 208397-1], entitled “System For Regulating A Cooling Fluid Within A Turbomachine”, filed May 1, 2007; which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present application relates generally to a cooling system on a turbomachine; and more particularly to, a system for regulating a cooling fluid within a wheelspace area of a turbomachine. 
         [0003]    In some turbomachines, such as gas turbines, a portion of the air compressed by the compressor is typically diverted from combustion to cool various stationary and rotating components or to purge cavities within a gas turbine. The diverted airflow (hereinafter “cooling fluid”,) consumes a considerable amount of the total airflow compressed by the compressor. The diverted cooling fluid is not combusted, reducing the performance of the gas turbine. Regulating and controlling the cooling fluid can dramatically increase the performance of the turbine. 
         [0004]    Typically, the cooling fluid is extracted from the compressor, bypasses the combustion system, and flows through a cooling circuit. The cooling circuit is typically located near various turbine components including the rotor compressor-turbine joint (hereinafter “marriage joint”), and various wheelspace areas. The cooling circuit is typically integrated with a seal system. Relatively tight clearances may exist between the seal system components and the gas turbine rotor. 
         [0005]    The seal system may include labyrinth seals located between rotating and stationary components. The typical leakages that may occur through the labyrinth seal clearances are commonly used for cooling or purging areas downstream of the seals. For example, a high-pressure packing seal system (HPPS) may include a labyrinth and brush seal arrangement, wherein the leakage flow past the HPPS cools the downstream components including the wheelspace areas. The effectiveness of the cooling circuit is highly dependent on the performance of the HPPS. 
         [0006]    The configuration of the cooling circuit determines whether or not adequate cooling fluid flows to the aforementioned turbine components. The cooling circuit may include a chamber that directs the cooling fluid flow to a specific wheelspace area. 
         [0007]    There may be a few issues with the currently known seal systems. Wear may enlarge the seal system clearances. Seals may wear during a “trip” (an emergency shutdown of the turbomachine). Also, seals gradually wear over time from gas turbine operation. Wear allows excessive cooling fluid to flow downstream of the seals; reducing the overall efficiency of the gas turbine. The unpredictable nature of the seal system wear occurrence does not allow for a deterministic flow of the cooling fluid through the cooling circuit. Furthermore, known seal systems do not compensate for seal system wear. Therefore, the known seal systems do not provide a way to adjust the amount of cooling fluid flowing to the wheelspace areas. 
         [0008]    For the foregoing reasons, there is a desire for a system that allows regulating the cooling fluid passing into the wheelspace areas of the gas turbine. The system should adequately cool while improving the gas turbine efficiency. The system should also provide for a deterministic flow through the cooling circuit. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0009]    Certain embodiments commensurate in scope with the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather these embodiments are intended only to provide a brief summary of possible forms of the invention. Indeed, the invention may encompass a variety of forms that may be similar to or different from the embodiments set forth below. 
         [0010]    In an embodiment of the present invention, a system for regulating a cooling fluid, the system comprising: a turbomachine comprising: a compressor section comprising an inner barrel casing; a compressor discharge casing; and bypass chambers that allow a cooling fluid to pass from the inner barrel casing to the compressor discharge casing; a turbine section comprising rotating components; stationary components; and wheelspace areas, wherein each wheelspace area comprises a rotating component and a stationary component and each bypass chamber allows for the cooling fluid to pass from the compressor section to the wheelspace area; and a nozzle cooling circuit comprising a primary passage and a header, which are both substantially located within each stationary component, wherein a first end of the primary passage receives the cooling fluid and a second end of the primary passage is connected to header such that the cooling fluid flows from the primary passage to the header; wherein the header comprises an upstream port and a downstream port that allows the cooling fluid to discharge from the header. 
         [0011]    In an alternate embodiment of the present invention, a system for regulating a cooling fluid, the system comprising: a gas turbine comprising: a combustion system that generates a working fluid; a compressor section comprising an inner barrel casing; a compressor discharge casing; and bypass chambers; wherein the cooling fluid flows through the inner barrel casing to the compressor discharge casing; a turbine section comprising rotating blades; diaphragms; nozzles; and wheelspace areas, wherein each wheelspace area comprises a series of rotating blades, a diaphragm, and a nozzle, and each bypass chamber allows the cooling fluid to flow from the compressor discharge casing to the wheelspace areas; and a nozzle cooling circuit substantially located within each stationary component, wherein the nozzle cooling circuit comprises a primary passage and a header; wherein a first end of the primary passage receives the cooling fluid and a second end of the primary passage is connected to header and the cooling fluid flows from the primary passage to the header; wherein the header comprises an upstream port and a downstream port that allows the cooling fluid to discharge from the header and mixing with the working fluid. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0012]    These and other features, aspects, and advantages of the present invention may become better understood when the following detailed description is read with reference to the accompanying figures (FIGS) in which like characters represent like elements/parts throughout the FIGS. 
           [0013]      FIG. 1  is a schematic view, in cross-section, of a gas turbine, illustrating the environment in which an embodiment of the present invention operates. 
           [0014]      FIG. 2  is an enlarged view of a portion of the gas turbine illustrated in  FIG. 1 . 
           [0015]      FIG. 3  illustrates a schematic view of a stationary component of  FIG. 2  having a known nozzle cooling circuit. 
           [0016]      FIG. 4  illustrates a schematic view of a stationary component of  FIG. 2  having a nozzle cooling circuit, in accordance with an embodiment of the present invention. 
           [0017]      FIG. 5  illustrates an exploded schematic view of the stationary. component of  FIG. 4 , in accordance with an embodiment of the present invention. 
           [0018]      FIG. 6  illustrates a schematic view of the stationary component of  FIG. 4  in use, in accordance with an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in an engineering or design project, numerous implementation-specific decisions are made to achieve the specific goals, such as compliance with system-related and/or business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
         [0020]    Detailed example embodiments are disclosed herein. However, specific structural and functional details disclosed herein are merely representative for purposes of describing example embodiments. Embodiments of the present invention may, however, be embodied in many alternate forms, and should not be construed as limited to only the embodiments set forth herein. 
         [0021]    Accordingly, while example embodiments are capable of various modifications and alternative forms, embodiments thereof are illustrated by way of example in the figures and will herein be described in detail. It should be understood, however, that there is no intent to limit example embodiments to the particular forms disclosed, but to the contrary, example embodiments are to cover all modifications, equivalents, and alternatives falling within the scope of the present invention. 
         [0022]    The terminology used herein is for describing particular embodiments only and is not intended to be limiting of example embodiments. 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. The terms “comprises”, “comprising”, “includes” and/or “including”, when used herein, 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. 
         [0023]    Although the terms first, second, etc may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any, and all, combinations of one or more of the associated listed items. 
         [0024]    Certain terminology may be used herein for the convenience of the reader only and is not to be taken as a limitation on the scope of the invention. For example, words such as “upper”, “lower”, “left”, “right”, “front”, “rear”, “top”, “bottom”, “horizontal”, “vertical”, “upstream”, “downstream”, “fore”, “aft”, and the like; merely describe the configuration shown in the FIGS. Indeed, the element or elements of an embodiment of the present invention may be oriented in any direction and the terminology, therefore, should be understood as encompassing such variations unless specified otherwise. 
         [0025]    The present invention may be applied to a variety of air-ingesting turbomachines. This may include, but is not limiting to, heavy-duty gas turbines, aero-derivatives, or the like. Although the following discussion relates to the gas turbine illustrated in  FIG. 1 , embodiments of the present invention may be applied to a gas turbine with a different configuration. For example, but not limiting of, the present invention may apply to a gas turbine with different, or additional, components than those illustrated in  FIG. 1 . 
         [0026]    Referring now to the FIGS, where the various numbers represent like components throughout the several views,  FIG. 1  is a schematic view, in cross-section, of a portion of a gas turbine, illustrating the environment in which an embodiment of the present invention operates. In  FIG. 1 , a gas turbine  100  includes: a compressor section  105 ; a combustion section  150 ; and a turbine section  180 . 
         [0027]    Generally, the compressor section  105  includes a plurality of rotating blades  110  and stationary vanes  115  structured to compress a fluid. The compressor section  105  may also include an extraction port  120 , an inner barrel  125 , a compressor discharge casing  130 , a marriage joint  135 , and a marriage joint bolt  137 . 
         [0028]    The combustion section  150  generally includes a plurality of combustion cans  155 , a plurality of fuel nozzles  160 , and a plurality of transition sections  165 . The plurality of combustion cans  155  may be coupled to a fuel source. Within each combustion can  155 , compressed air is received from the compressor section  105  and mixed with fuel received from the fuel source. The air and fuel mixture is ignited and creates a working fluid. The working fluid generally proceeds from the aft end of the plurality of fuel nozzles  160  downstream through the transition section  165  into the turbine section  180 . 
         [0029]    The turbine section  180  may include a plurality of rotating components  185 ; a plurality of stationary components  190 , which include nozzles and diaphragms; and a plurality of wheelspace areas  195 . The turbine section  180  converts the working fluid to a mechanical torque. 
         [0030]    Typically, during the operation of the gas turbine  100 , a plurality of components experience high temperatures and may require cooling or purging. These components may include a portion of the compressor section  105 , the marriage joint  135 , and the plurality of wheelspace areas  195 . 
         [0031]    The extraction port  120  draws cooling fluid from the compressor section  105 . The cooling fluid bypasses the combustion section  150 , and flows through a cooling circuit  200  (illustrated in  FIG. 2 ), for cooling or purging various components, including the marriage joint  135 , and a plurality of wheelspace areas  195 . 
         [0032]    Referring now to  FIG. 2 , which is a close-up view of the gas turbine illustrated in  FIG. 1 .  FIG. 2  illustrates a non-limiting example of an embodiment of the cooling circuit  200 . The flow path of the cooling circuit  200  may start at the extraction port  120  (illustrated in  FIG. 1 ), flow through a portion of the compressor discharge casing  130 , the inner barrel casing  125 , and then a cavity at the aft end of the compressor section  105 . Next, the cooling circuit  200  may reverse direction, flowing past the marriage joint  135 , the seal system components  140 , and to the wheelspace area  195 . 
         [0033]      FIG. 3  illustrates a schematic view of the stationary component  190  of  FIG. 2  having a known nozzle cooling circuit. The stationary component  190  comprises a nozzle cooling circuit  300  that is located internally. The nozzle cooling circuit  300  allows the cooling fluid to cool the stationary component  190  from within. The nozzle cooling circuit  300  receives the cooling fluid, illustrated in the FIGS by the arrows. The currently known circuit  300  includes a path that may direct the cooling fluid to discharge on an upstream side of the stationary component  190 . After exiting the stationary component  190 , the cooling fluid may flow downstream through the seal system components  140  and then engage a downstream side of the stationary component  190 . 
         [0034]      FIG. 4  illustrates a schematic view of a stationary component of  FIG. 2  having a nozzle cooling circuit, in accordance with an embodiment of the present invention. The stationary component  190  comprises a nozzle cooling circuit  400  that is located internally. The nozzle cooling circuit  400  allows the cooling fluid to cool the stationary component  190  in a more controlled and efficient way. The nozzle cooling circuit  400  receives the cooling fluid which is illustrated in the FIGS by the arrows. By comparing  FIG. 3  and  FIG. 4 , the benefits of embodiments of the present invention are shown. Here, the cooling fluid flows from a primary passage  405  to a header  410 ; which allows the cooling fluid to discharge from the stationary component  190  in both upstream and downstream directions. This allows for a more efficient cooling of the downstream end of the stationary component  190 . 
         [0035]      FIG. 5  illustrates an exploded schematic view of the stationary component of  FIG. 4 , in accordance with an embodiment of the present invention. An embodiment of the nozzle cooling circuit  400  may comprise a primary passage  405 , a header  410 , a port  415 , and a tuning plug  420 . 
         [0036]    An embodiment of the primary passage  405  may comprise a first end and a second end. The first end may be positioned to receive the cooling fluid. The second end located at an opposite end of the primary passage  405 . The second end may be connected to the header  410  in a manner that allows the cooling fluid to enter. In an embodiment of the present invention the nozzle cooling circuit  400  may comprise one primary passage  405 . In an alternate embodiment of the present invention, the nozzle cooling circuit  400  may comprise multiple primary passages  405 . Here, each primary passage  405  may comprise a dedicated header  410 . 
         [0037]    An embodiment of the header  410  may have the form of a through-hole, or the like. Each end of the header  410  may be enclosed via a cap  425 , as illustrated, for example, in  FIG. 5 . The cap  425  may be connected to the header  410 , via welding, threaded connections, or other connection means. 
         [0038]    Located upstream of the end of the header  410  are an upstream port  415  and a downstream port  415 , as illustrated in  FIG. 6 . The ports  415  may be considered an angled passage. The ports  415  are angularly positioned relative to the header  410 . This angle  430  may induce a pre-swirl on the cooling fluid exiting each port  415  and entering the wheelspace area  195 . In an embodiment of the present invention, the angle  430  may comprise a range of from about 0 degrees to about 100 degrees, depending on the physical constraints associated with the associated components. The pre-swirl allows the cooling fluid to flow in nearly the same direction and orientation as the rotating components  185  and the working fluid. This may improve the mixing of the cooling fluid with the working fluid, increasing the cooling efficiency. 
         [0039]    The upstream ports  415  allows the cooling fluid to discharge the near an upstream end of the stationary component  190 . The downstream port  415  allows the cooling fluid to discharge near a downstream end of the stationary component  190 . The tuning plug  420  allows a user to control the flow of the cooling fluid exiting a designated port  415 . The tuning plug  420  comprises a through hole, or the like, which allows the cooling fluid to flow from the header  410  and discharge via a port  415 . The tuning plug  420  may assist the port  415  with directing the cooling fluid toward an outer surface of the stationary component  190 . The tuning plug  420  may adjust the mechanical properties of the cooling fluid exiting the nozzle cooling circuit  400 . These properties may include, but are not limited to: velocity, flowrate, and pressure. 
         [0040]    An embodiment of the tuning plug  420  may comprise a threaded connection that allows mating with the portion of the port  415 . An alternate embodiment of the tuning plug  420  may be press fit into the port  415 . Another alternate embodiment of the tuning plug  420  may comprise a variable internal diameter through which the cooling fluid discharges from the header  410 , providing more control over the aforementioned properties. 
         [0041]      FIG. 6  illustrates a schematic view of the stationary component  190  of  FIG. 4  in use, in accordance with an embodiment of the present invention. In use, an embodiment of the present invention may function as follows. The nozzle cooling circuit  400  receives the cooling fluid, represented in  FIG. 4  by the arrows. Next, the cooling fluid may flow through the primary passage  405 . Next the cooling fluid may enter the header  410 . Here, the flow of the cooling fluid may diverge. A portion may flow towards the upstream port  415 , discharging via the connected tuning plug  420 . The remaining portion may flow towards the downstream port  415 , discharging via the connected tuning plug  420 . 
         [0042]    Although specific embodiments have been illustrated and described herein, those of ordinary skill in the art appreciate that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiments shown and that the invention has other applications in other environments. This application is intended to cover any adaptations or variations of the present invention. The following claims are in no way intended to limit the scope of the invention to the specific embodiments described herein. 
         [0043]    As one of ordinary skill in the art will appreciate, the many varying features and configurations described above in relation to the several embodiments may be further selectively applied to form other possible embodiments of the present invention. Those in the art will further understand that all possible iterations of the present invention are not provided or discussed in detail, even though all combinations and possible embodiments embraced by the several claims below or otherwise are intended to be part of the instant application. In addition, from the above description of several embodiments of the invention, those skilled in the art will perceive improvements, changes, and modifications. Such improvements, changes, and modifications within the skill of the art are also intended to be covered by the appended claims. Further, it should be apparent that the foregoing relates only to the described embodiments of the present application and that numerous changes and modifications may be made herein without departing from the spirit and scope of the application as defined by the following claims and the equivalents thereof.