Patent Publication Number: US-2017363007-A1

Title: Isothermalized cooling of gas turbine engine components

Description:
BACKGROUND 
     This disclosure relates to gas turbine engines, and more particularly to gas turbine engine components having lattice structures. The lattice structures include heat transfer devices configured to isothermally cool portions of the components. 
     Gas turbine engines typically include a compressor section, a combustor section, and a turbine section. In general, during operation, air is pressurized in the compressor section and is mixed with fuel and burned in the combustor section to generate hot combustion gases. The hot combustion gases flow through the turbine section, which extracts energy from the hot combustion gases to power the compressor section and other gas turbine engine loads. 
     Due to exposure to hot combustion gases, numerous components of the gas turbine engine include internal cooling schemes that circulate airflow to cool the component during engine operation. Thermal energy is transferred from the component to the airflow as the airflow circulates through the cooling scheme to thermally manage the component. It is desirable to provide cooling schemes that are efficient and that provide structural integrity. 
     SUMMARY 
     A component according to an exemplary aspect of the present disclosure includes, among other things, a first wall section, a second wall section spaced from the first wall section, a plurality of branches between the first wall section and the second wall section, and a heat transfer device disposed either between adjacent branches of the plurality of branches or inside at least one branch of the plurality of branches. 
     In a further non-limiting embodiment of the foregoing component, the heat transfer device includes a wick structure and a working medium. 
     In a further non-limiting embodiment of either of the foregoing components, the wick structure includes a sintered metal powder. 
     In a further non-limiting embodiment of any of the foregoing components, the heat transfer device is an enclosed structure that holds a working medium. 
     In a further non-limiting embodiment of any of the foregoing components, passages extend between the adjacent branches of the plurality of branches. 
     In a further non-limiting embodiment of any of the foregoing components, the heat transfer device is located within one of the passages. 
     In a further non-limiting embodiment of any of the foregoing components, the component is an additively manufactured component. 
     In a further non-limiting embodiment of any of the foregoing components, the heat transfer device is disposed between the adjacent branches of the plurality of branches and a second heat transfer device is disposed inside the at least one branch of the plurality of branches. 
     In a further non-limiting embodiment of any of the foregoing components, the heat transfer device includes an evaporation section and a condenser section. 
     In a further non-limiting embodiment of any of the foregoing components, a working medium of the heat transfer device moves between the evaporation section and the condenser section in response to absorbing or releasing heat. 
     In a further non-limiting embodiment of any of the foregoing components, locations of the evaporation section and the condenser section vary based on localized temperatures of the component. 
     In a further non-limiting embodiment of any of the foregoing components, the first wall section and the second wall section are part of a blade, a vane, a blade outer air seal (BOAS), a combustor panel, or a turbine exhaust case liner of a gas turbine engine. 
     In a further non-limiting embodiment of any of the foregoing components, the heat transfer device includes a first working medium and a second heat transfer device of the component includes a second working medium. 
     A component according to another exemplary aspect of the present disclosure includes, among other things, a wall and a lattice structure arranged inside the wall. The lattice structure includes a plurality of nodes, a plurality of branches that extend between the plurality of nodes, a plurality of passages extending between the plurality of nodes and the plurality of branches, and a heat transfer device adapted to transfer thermal energy within the lattice structure by selectively evaporating and condensing a working medium. 
     In a further non-limiting embodiment of the foregoing component, the lattice structure is a vascular engineered lattice structure. 
     In a further non-limiting embodiment of either of the foregoing components, the vascular engineered lattice structure is configured such that airflow is communicated through the plurality of passages and the heat transfer device is disposed inside at least one node of the plurality of nodes or inside at least one branch of the plurality of branches. 
     In a further non-limiting embodiment of any of the foregoing components, the vascular engineered lattice structure includes a hollow lattice structure in which airflow is communicated inside the plurality of nodes and the plurality of passages and the heat transfer device is disposed within at least one passage of the plurality of passages. 
     In a further non-limiting embodiment of any of the foregoing components, the working medium is at least partially carried by a wick structure of the heat transfer device. 
     In a further non-limiting embodiment of any of the foregoing components, the wick structure includes a sintered metal powder. 
     In a further non-limiting embodiment of any of the foregoing components, the heat transfer device is an enclosed structure that holds the working medium. 
     The embodiments, examples, and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible. 
     The various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic, cross-sectional view of a gas turbine engine. 
         FIG. 2  illustrates a component of a gas turbine engine. 
         FIG. 3  illustrates a lattice structure of a gas turbine engine component. 
         FIG. 4  illustrates another lattice structure. 
         FIGS. 5A and 5B  illustrate another lattice structure. 
         FIGS. 6A and 6B  illustrate yet another lattice structure. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure details a lattice structure for thermally managing gas turbine engine components. The lattice structure includes a plurality of branches, or struts, disposed inside a wall or between adjacent wall sections of the component. A heat transfer device of the lattice structure may be disposed between adjacent branches of the plurality of branches, disposed inside one or more branches of the plurality of branches, or both. The heat transfer device functions like a heat pipe to evenly and effectively cool the component without a significant net energy loss. These and other features are discussed in greater detail in the following paragraphs of this detailed description. 
       FIG. 1  schematically illustrates a gas turbine engine  20 . The exemplary gas turbine engine  20  is a two-spool turbofan engine that generally incorporates a fan section  22 , a compressor section  24 , a combustor section  26 , and a turbine section  28 . Alternative engines might include an augmenter section (not shown) among other systems for features. The fan section  22  drives air along a bypass flow path B, while the compressor section  24  drives air along a core flow path C for compression and communication into the combustor section  26 . The hot combustion gases generated in the combustor section  26  are expanded through the turbine section  28 . Although depicted as a turbofan gas turbine engine in the disclosed non-limiting embodiment, it should be understood that the concepts described herein are not limited to turbofan engines and these teachings could extend to other types of engines, including but not limited to, three-spool engine architectures. 
     The gas turbine engine  20  generally includes a low speed spool  30  and a high speed spool  32  mounted for rotation about an engine centerline longitudinal axis A. The low speed spool  30  and the high speed spool  32  may be mounted relative to an engine static structure  33  via several bearing systems  31 . It should be understood that other bearing systems  31  could alternatively or additionally be provided. 
     The low speed spool  30  generally includes an inner shaft  34  that interconnects a fan  36 , a low pressure compressor  38 , and a low pressure turbine  39 . The inner shaft  34  can be connected to the fan  36  through a geared architecture  45  to drive the fan  36  at a lower speed than the low speed spool  30 . The high speed spool  32  includes an outer shaft  35  that interconnects a high pressure compressor  37  and a high pressure turbine  40 . In this non-limiting embodiment, the inner shaft  34  and the outer shaft  35  are supported at various axial locations by bearing systems  31  positioned within the engine static structure  33 . 
     A combustor  42  is arranged between the high pressure compressor  37  and the high pressure turbine  40 . A mid-turbine frame  44  may be arranged generally between the high pressure turbine  40  and the low pressure turbine  39 . The mid-turbine frame  44  supports one or more bearing systems  31  of the turbine section  28 . The mid-turbine frame  44  may include one or more airfoils  46  that extend within the core flow path C. 
     The inner shaft  34  and the outer shaft  35  are concentric and rotate via the bearing systems  31  about the engine centerline longitudinal axis A, which is co-linear with their longitudinal axes. The core airflow is compressed by the low pressure compressor  38  and the high pressure compressor  37 , is mixed with fuel and burned in the combustor  42 , and is then expanded over the high pressure turbine  40  and the low pressure turbine  39 . The high pressure turbine  40  and the low pressure turbine  39  rotationally drive the respective high speed spool  32  and the low speed spool  30  in response to the expansion. 
     The pressure ratio of the low pressure turbine  39  can be pressure measured prior to the inlet of the low pressure turbine  39  as related to the pressure at the outlet of the low pressure turbine  39  and prior to an exhaust nozzle of the gas turbine engine  20 . In one non-limiting embodiment, the bypass ratio of the gas turbine engine  20  is greater than about ten (10:1), the fan diameter is significantly larger than that of the low pressure compressor  38 , and the low pressure turbine  39  has a pressure ratio that is greater than about five (5:1). It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present disclosure is applicable to other gas turbine engines, including direct drive turbofans. 
     In another non-limiting embodiment of the exemplary gas turbine engine  20 , a significant amount of thrust is provided by the bypass flow path B due to the high bypass ratio. The fan section  22  of the gas turbine engine  20  is designed for a particular flight condition—typically cruise at about 0.8 Mach and about 35,000 feet. This flight condition, with the gas turbine engine  20  at its best fuel consumption, is also known as bucket cruise Thrust Specific Fuel Consumption (TSFC). TSFC is an industry standard parameter of fuel consumption per unit of thrust. 
     Fan Pressure Ratio is the pressure ratio across a blade of the fan section  22  without the use of a Fan Exit Guide Vane system. The low Fan Pressure Ratio according to one non-limiting embodiment of the example gas turbine engine  20  is less than 1.45. Low Corrected Fan Tip Speed is the actual fan tip speed divided by an industry standard temperature correction of [(Tram ° R)/(518.7° R)] 0.5 . The Low Corrected Fan Tip Speed according to one non-limiting embodiment of the example gas turbine engine  20  is less than about 1150 fps (351 m/s). 
     The compressor section  24  and the turbine section  28  each include alternating rows of rotor assemblies and vane assemblies (shown schematically) that carry airfoils that extend into the core flow path C. For example, the rotor assemblies carry a plurality of rotating blades  25 , while each vane assembly carries a plurality of vanes  27  that extend into the core flow path C. The blades  25  create or extract energy (in the form of pressure) from the core airflow that is communicated through the gas turbine engine  20  along the core flow path C. The vanes  27  direct the core airflow to the blades  25  to either add or extract the energy. 
     Various components of the gas turbine engine  20 , including but not limited to the airfoils of the blades  25  and the vanes  27  of the compressor section  24  and the turbine section  28 , may be subjected to repetitive thermal cycling under widely ranging temperatures and pressures. The hardware of the turbine section  28  is particularly subjected to relatively extreme operating conditions. Therefore, some components may require cooling schemes for cooling the parts during engine operation. 
     Among other features, this disclosure relates to gas turbine engine component cooling schemes that include lattice structures inside the walls of the gas turbine engine components. The lattice structures described herein provide effective localized cooling, and is some embodiments, provide isothermalized cooling inside components subject to compressor air or hot combustion gases communicated through the core flow path C. Isothermalized cooling evenly cools the components and substantially reduces hot spots within the components while achieving a near zero net energy loss. 
       FIG. 2  illustrates a component  50  that can be incorporated into a gas turbine engine, such as the gas turbine engine  20  of  FIG. 1 . The component  50  includes a body portion  52  that axially extends between a leading edge portion  54  and a trailing edge portion  56 . The body portion  52  may further include a first (pressure) side wall  58  and a second (suction) side wall  60  that are spaced apart from one another and axially extend between the leading edge portion  54  and the trailing edge portion  56 . Although shown in cross-section, the body portion  52  would also extend radially across a span. 
     In the illustrated non-limiting embodiment, the body portion  52  is representative of an airfoil. For example, the body portion  52  could be an airfoil that extends from a platform and a tip portion (i.e., where the component is a blade), or could alternatively extend between inner and outer platforms (i.e., where the component  50  is a vane). In yet another non-limiting embodiment, the component  50  is a non-airfoil component, including but not limited to, a blade outer air seal (BOAS), a combustor liner, a turbine exhaust case liner, or any other part that requires dedicated cooling. 
     A gas path  62  is communicated axially downstream through the gas turbine engine  20  in a direction that extends from the leading edge portion  54  toward the trailing edge portion  56  of the body portion  52 . The gas path  62  represents the communication of core airflow along the core flow path C (see, e.g.,  FIG. 1 ). 
     A cooling scheme  64  is disposed inside the body portion  52  for cooling the internal and external surface areas of the component  50 . For example, the cooling scheme  64  can include one or more cavities  72  that may radially, axially, and/or circumferentially extend inside the body portion  52  to establish cooling passages for receiving an airflow  68  (or some other fluid). The airflow  68  may be communicated into one or more of the cavities  72  from an airflow source  70  that is external to the component  50  to cool the component  50 . In one non-limiting embodiment, the airflow  68  is communicated to the cooling scheme  64  through a root portion of the component  50  (e.g., where the component is a blade). 
     The airflow  68  is generally a lower temperature than the airflow of the gas path  62  that is communicated across an exterior of the body portion  52 . In one particular non-limiting embodiment, the airflow  68  is a bleed airflow that can be sourced from the compressor section  24  or any other portion of the gas turbine engine  20  that has a lower temperature than the component  50 . The airflow  68  is circulated through the cooling scheme  64  to transfer thermal energy from the component  50  to the airflow  68 , thereby cooling the component  50 . 
     In a non-limiting embodiment, the exemplary cooling scheme  64  includes a plurality of cavities  72  that extend inside of the body portion  52 . However, the cooling scheme  64  is not necessarily limited to the configuration shown, and it will be appreciated that a greater or fewer number of cavities, including only a single cavity, may be defined inside of the body portion  52 . The cavities  72  communicate the airflow  68  through the cooling scheme  64 , such as along a serpentine path or a linear path, to cool the body portion  52 . 
     Ribs  74  extend between the first side wall  58  and the second side wall  60  of the body portion  52 . The ribs  74  also radially extend over a span of the body portion  52 . 
     The exemplary cooling scheme  64  may additionally include one or more lattice structures  80  that are disposed inside sections of the body portion  52  of the component  50 . For example, discrete sections of one or more walls of the component  50  may embody a lattice structure, or the entire component  50  could be constructed of lattice structures. Exemplary lattice structures are described in further detail below. 
       FIGS. 3 and 4  illustrate a section  99  of the component  50 . The section  99  could be any portion of a gas turbine engine component. For example, with reference to the non-limiting embodiment of  FIG. 2 , the section  99  could be located near the leading edge portion  54 , the trailing edge portion  56 , the first (pressure) side wall  58 , the second (suction) side wall  60 , or any other location of the component  50  that is subject to relatively high heat loads. 
     A lattice structure  80  extends between a first wall section  82  and a second wall section  84  of the section  99 . The term “lattice structure” denotes a structure that can be heated or cooled by allowing airflow to be circulated through openings formed within the lattice structure. The first wall section  82  and the second wall section  84  could be part of a single wall or could be different walls of the component  50 . Thus, in a non-limiting embodiment, the lattice structure  80  is considered to be disposed “inside” a wall or a rib of the component  50 . 
     The first wall section  82  is spaced from the second wall section  84 . The first wall section  82  is exposed to the gas path  62 , whereas the second wall section  84  is remote from the gas path  62 . For example, the second wall section  84  could face toward or into a cooling source cavity  72  of the cooling scheme  64  (see  FIG. 2 ). The lattice structure  80  includes a thickness T extending from the first wall section  82  to the second wall section  84 . The thickness T could be any dimension. 
     In a non-limiting embodiment, the lattice structure  80  includes a plurality of branches  86  disposed between the first wall section  82  and the second wall section  84 . In a non-limiting embodiment, the branches  86  extend across the entire thickness T from the first wall section  82  to the second wall section  84 . The branches  86  may extend orthogonally or non-orthogonally relative to the first and second wall sections  82 ,  84 . In other non-limiting embodiments, a portion of the branches  86  extend orthogonally relative to the first and second wall sections  82 ,  84  while another portion of the branches  86  extend non-orthogonally relative to the first and second wall sections  82 ,  84 . In yet another non-limiting embodiment, a portion of the branches  86  extend between other branches  86 . In yet another non-limiting embodiment, a portion of the branches  86  extend between branches  86  and wall portions. A passage  88  extends between adjacent branches  86  of the lattice structure  80 . 
     The lattice structure  80  may additionally include one or more heat transfer devices  90 . Each heat transfer device  90  is a sealed or enclosed structure integrally formed as part of the lattice structure  80 . The heat transfer devices  90  include a wick structure  92 , or capillary action structure such as a porous medium, and a working medium  94  that can move within the heat transfer device  90  and the wick structure  92  to transfer thermal energy. The enclosed structure of the heat transfer device  90  holds the working medium  94 . 
     The heat transfer devices  90  additionally include a vaporization section  96  and a condenser section  98 . It should be recognized that the particular sizes, shapes, and locations of the vaporization section  96  and the condenser section  98  can vary. In fact, in a non-limiting embodiment, the sizes, shapes, and locations of these sections are defined by the local temperatures at any given time within the section  99  of the component  50 . Thus, the locations of the vaporization section  96  and the condenser section  98  could change depending on the operating environment within which the component  50  has been disposed. 
     In another non-limiting embodiment, the heat transfer devices  90  function like heat pipes that use an evaporative cooling cycle to transfer thermal energy by continuously evaporating and condensing the working medium  94 . For example, the heat transfer devices  90  may utilize an evaporative cooling cycle to transfer thermal energy from the component  50  to cooling flow such as air  68  passing through the lattice structure  80 . Thermal energy absorbed by the component  50  from hot combustion gases, such as at the first wall section  82 , heats the vaporization section  96  of one or more of the heat transfer devices  90 . This causes the working medium  94  in the vaporization section  96  to evaporate. The relatively cool air  68  communicated through the lattice structure  80  absorbs thermal energy from the condenser section  98 , thus causing the (vaporized) working medium  94  to condense back into a liquid phase. 
     The working medium  94  physically moves between the vaporization section  96  and the condenser section  98  to transfer thermal energy between the locations where the evaporation and condensation occur within the heat transfer devices  90 . The wick structures  92  primarily facilitate the movement of the liquid working medium  94 . In a non-limiting embodiment, the wick structure  92  of the heat transfer device  90  is a sintered metal powder. The sintered metal powder may be additively manufactured. Other wick or capillary action structures are also contemplated within the scope of this disclosure. 
     The composition of the working medium  94  of each heat transfer device  90  may be selected according to the particular operating conditions at which heat transfer is desired. Typically, working media conventionally used with evaporative cooling cycles are dependent upon operation within a particular range of temperature conditions (as well as pressure conditions). It is therefore necessary to select a suitable working medium based on the particular conditions under which each heat transfer device  90  is expected to operate. Temperatures in gas turbine engines can reach 1,649° C. (3,000° F.) or more, although actual engine temperatures will vary for different applications, and under different operating conditions. For example, during operation, the gas turbine engine is configured such that the average gas path temperature will generally not exceed the maximum temperature limits for the materials (e.g., metals and ceramics) used in and along the core flow path C. A non-limiting list of potential working medium is provided in Table 1, although those skilled in the art will recognize that other working medium could alternatively or additionally be utilized. In addition, it should be recognized that different working medium may be utilized within separate heat transfer devices of a given lattice structure. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                   
                   
                 Approximate 
               
               
                 Working 
                 Melting Point 
                 Boiling Point 
                 Useful Range 
               
               
                 Medium 
                 (° C.) 
                 (° C. at 101.3 kPa) 
                 (° C.) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 Helium 
                 −271 
                 −261 
                 −271 to −269  
               
               
                 Nitrogen 
                 −210 
                 −196 
                 −203 to −160  
               
               
                 Ammonia 
                 −78 
                 −33 
                 −60 to 100  
               
               
                 Acetone 
                 −95 
                 57 
                  0 to 120 
               
               
                 Methanol 
                 −98 
                 64 
                 10 to 130 
               
               
                 Flutec PP2 ™ 
                 −50 
                 76 
                 10 to 160 
               
               
                 Ethanol 
                 −112 
                 78 
                  0 to 130 
               
               
                 Water 
                 0 
                 100 
                 30 to 200 
               
               
                 Toluene 
                 −95 
                 110 
                 50 to 200 
               
               
                 Mercury 
                 −39 
                 361 
                 250 to 650  
               
               
                 Sodium 
                 98 
                 892 
                 600 to 1200 
               
               
                 Lithium 
                 179 
                 1340 
                 1000 to 1800  
               
               
                 Silver 
                 960 
                 2212 
                 1800 to 2300  
               
               
                   
               
            
           
         
       
     
     In a first non-limiting embodiment, shown in  FIG. 3 , the heat transfer devices  90  are disposed in the passages  88  that extend between adjacent branches  86  of the lattice structure  80 . Although depicted as such in this non-limiting embodiment, it is not necessary to provide a heat transfer device  90  in each and every passage  88  of the lattice structure  80 . Airflow  68  can be communicated inside the branches  86 . Although not shown, the lattice structure  80  includes an inlet and an outlet for receiving and expelling the cooling airflow  68 . 
     In a first non-limiting embodiment, the airflow  68  absorbs thermal energy from the heat transfer devices  90  as it passes through the branches  86 . In this way, the lattice structure  80  isothermally cools the component  50  with a near zero net energy loss. In this cooling embodiment, the temperature of the airflow  68  is lower than that of the component to be cooled. 
     In an alternative embodiment, the lattice structure  80  can be utilized to heat the component  50 . In such an embodiment, the airflow  68  is a heating airflow that includes a temperature that is higher than that of the component to be heated. 
     In a second non-limiting embodiment, shown in  FIG. 4 , the heat transfer devices  90  are disposed inside the branches  86  of the lattice structure  80 . The heat transfer devices  90  could be disposed in one or more of the branches  86 . Airflow  68  is communicated through the passages  88 , or hollow openings, located between adjacent branches  86 . The airflow  68  absorbs thermal energy from the branches  86 , via the heat transfer devices  90 , as it matriculates through the passages  88 . In this way, the lattice structure  80  isothermally cools the component  50  with a near zero net energy loss. In an alternative embodiment, the lattice structure  80  can be utilized to heat the component  50 . 
       FIGS. 5A and 5B  illustrate another lattice structure  180 . In this embodiment, the lattice structure  180  may be referred to as a vascular engineered lattice structure. The vascular engineered lattice structure may be incorporated into any section or sections of a gas turbine engine component. In this disclosure, the term “vascular engineered lattice structure” denotes a structure of known surface and flow areas that includes a specific structural integrity. 
     As discussed in greater detail below, the vascular engineered lattice structure  180  of  FIGS. 5A and 5B  is a hollow lattice structure. The hollow lattice structure shown in  FIGS. 5A and 5B  defines a solid material with discrete, interconnected cooling passages that are connected through common nodes to control the flow of airflow  68  throughout the hollow lattice structure. 
     The specific design and configuration of the vascular engineered lattice structure  180  of  FIGS. 5A and 5B  is not intended to be limited to the specific configuration shown. It should be appreciated that because the vascular engineered lattice structure  180  is an engineered structure, the vascular arrangement of these structures can be tailored to the specific cooling and structural needs of any given gas turbine engine component. In other words, the vascular engineered lattice structure  180  can be tailored to match external heat load and local life requirements by changing the design and density of the vascular engineered lattice structure  180 . The actual design of any given vascular engineered lattice structure may depend on geometry requirements, pressure loss, local cooling flow, cooling air heat pickup, thermal efficiency, film effectiveness, overall cooling effectiveness, aerodynamic mixing, and produceability considerations, among other gas turbine engine specific parameters. In one non-limiting embodiment, the vascular engineered lattice structure  180  is sized based on a minimum size that can be effectively manufactured and that is not susceptible to becoming plugged by dirt or other debris. 
     The exemplary vascular engineered lattice structure  180  extends between a first wall section  182  and a second wall section  184  of a component  50 . The first wall section  182  is spaced from the second wall section  184 . The first wall section  182  may be exposed to the gas path  62 , whereas the second wall section  184  is remote from the gas path  62 . For example, the second wall section  184  could face into one of the cooling source cavities  72  of the cooling scheme  64  (see, e.g.,  FIG. 2 ). The vascular engineered lattice structure  180  includes a thickness T between the first wall section  182  and the second wall section  184 . The thickness T can be any dimension. 
     Airflow  68  migrates through the vascular engineered lattice structure  180  to cool the component  50 . In this non-limiting embodiment, the vascular engineered lattice structure  180  embodies a hollow configuration in which the airflow  68  may be circulated inside of the various passages defined by the vascular engineered lattice structure  180 . For example, the hollow configuration of the vascular engineered lattice structure  180  may establish a porous flow area for the circulation of airflow  68 . Additionally, airflow  68  could be communicated over and around the vascular engineered lattice structure  180 . 
     The lattice structure  80  or the vascular engineered lattice structure  180  can be manufactured by using a variety of manufacturing techniques. For example, the lattice structure  80  or the vascular engineered lattice structure  180  may be created using an additive manufacturing process such as direct metal laser sintering (DMLS). Another additive manufacturing process that can be used to manufacture the lattice structure  80  and the vascular engineered lattice structure  180  is electron beam melting (EBM). In another non-limiting embodiment, select laser sintering (SLS) or select laser melting (SLM) processes may be utilized. 
     In yet another non-limiting embodiment, a casting process can be used to create the lattice structure  80  or the vascular engineered lattice structure  180 . For example, an additive manufacturing process can be used to first produce a molybdenum based Refractory Metal Core (RMC) that can subsequently be used to cast the lattice structure  80  or the vascular engineered lattice structure  180 . In one embodiment, the additive manufacturing process includes utilizing a powder bed technology for direct fabrication of airfoil lattice geometry features, while in another embodiment, the additive manufacturing process can be used to produce “core” geometry features which can then be integrated and utilized directly in the investment casting process using a lost wax process. 
     The exemplary vascular engineered lattice structure  180  includes a plurality of nodes  192 , a plurality of branches  194  that extend between the nodes  192 , and a plurality of hollow passages  196  spanning between the branches  194  and the nodes  192 . The number, size and distribution of nodes  192 , branches  194 , and hollow passages  196  can vary from the specific configuration shown. In other words, the configuration illustrated by  FIGS. 5A and 5B  is but one possible design. 
     The branches  194  may extend orthogonally or non-orthogonally between the nodes  192 . The nodes  192  and branches  194  can be manufactured as a single contiguous structure made of the same material. In one non-limiting embodiment, the nodes  192  and branches  194  are uniformly distributed throughout the vascular engineered lattice structure  180 . In another non-limiting embodiment, the nodes  192  and branches  194  are non-uniformly distributed throughout the vascular engineered lattice structure  180 . 
     In this “hollow lattice” structure configuration, airflow  68  can be circulated inside hollow passages  197  of the nodes  192  and the branches  194  to cool the component  50  in the spaces between the wall sections  182 ,  184 . For example, the “hollow” lattice structure may include multiple continuous hollow spoke cavity passages  197  through which the airflow  68  is passed. The airflow  68  flows from each of the hollow branches  194  and coalesces into the nodes  192 , which serve as a plenum for the airflow  68  to be redistributed to the next set of hollow branches  194  and nodes  192 . The “hollow” lattice structure forms multiple, circuitous, continuous passages in which the airflow  68  flows to maximize the internal convective cooling surface area and coolant mixing. Additionally, airflow  68  could be communicated over and around the nodes  192  and branches  194  of the vascular engineered lattice structure  180 . 
     The nodes  192  and the branches  194  additionally act as structural members that can be tailored to “tune” steady and unsteady airfoil vibration responses in order to resist and optimally manage steady and unsteady pressure forces, centrifugal bending and curling stresses, as well as provide for improved airfoil local and section average creep and untwist characteristics and capability. In a non-limiting embodiment, one or more of the nodes  192  and the branches  194  include augmentation features  195  (shown schematically in  FIG. 5B ) that augment the heat transfer effect of the airflow  68  as it is communicated through the vascular engineered lattice structure  180 . The augmentation features  195  can also be made using the additive manufacturing processes describe above. 
     In yet another non-limiting embodiment, the vascular engineered lattice structure  180  include one or more heat transfer devices  190  disposed within the hollow passages  196  that extend between the various nodes  192  and branches  194 . The heat transfer devices  190  can be integrally manufactured as part of the contiguous structure of the vascular engineered lattice structure  180 . Although shown generically in this embodiment, the heat transfer devices  190  work in the substantially the same manner as the heat transfer devices  90  described above by utilizing an evaporative cooling cycle to transfer thermal energy from the component  50  to the airflow  68  as it is circulated inside the hollow passages  197  of the nodes  192  and the branches  194  of the vascular engineered lattice structure  180 . 
     As mentioned above, the vascular arrangement of the vascular engineered lattice structure  180  can be tailored to the specific cooling and structural needs of any given gas turbine engine component. For example, a first portion of the vascular engineered lattice structure  180  can include a different combination of nodes  192 , branches  194 , hollow passages  196 , and heat transfer devices  190  compared to a second portion of the vascular engineered lattice structure  180 . In one embodiment, a first portion of the vascular engineered lattice structure  180  may include a greater amount of cooling area whereas a second portion of the vascular engineered lattice structure  180  may provide a greater amount of structural area. 
       FIGS. 6A and 6B  illustrate yet another lattice structure  280 . In this embodiment, the lattice structure  280  is a vascular engineered lattice structure in which airflow is communicated over and around the lattice structure thereby governing flow and providing structural support. The vascular engineered lattice structure  280  is disposed between a first wall section  282  and a second wall section  284  of the component  50 . 
     The vascular engineered lattice structure  280  includes a plurality of nodes  292 , a plurality of branches  294  that extend between the nodes  292 , a plurality of open passages  296  between the branches  294  and the nodes  292 , and heat transfer devices  290  disposed inside at least a portion of the nodes  292  and the branches  294 . The nodes  292 , branches  294 , open passages  296 , and heat transfer devices  290  can be manufactured as a single contiguous structure, in one non-limiting embodiment. 
     In this lattice structure configuration, airflow  68  is circulated through the open passages  296  to cool the component  50  in the space between the wall sections  282 ,  284 . In other words, in contrast to the hollow lattice structure embodiment which communicates airflow inside the nodes  292  and the branches  294 , the airflow  68  is circulated over and around these parts as part of a porous flow area. For example, the lattice structure includes multiple continuous branches  294  over which airflow  68  is passed. The lattice structure forms circuitous passages for the airflow  68  to traverse around as it migrates through the vascular engineered lattice structure  280  to maximize the convective cooling surface area and coolant mixing around the nodes  292  and the branches  294 . The nodes  292  and the branches  294  additionally act as structural members that resist and dampen pressure, rotation forces, and vibratory loads. 
     The exemplary vascular engineered lattice structure  280  establishes a ratio of cooling area to structural area. The cooling area is established by the open passages  296 , while the nodes  292  and branches  294  determine the amount of structural area. In one embodiment, the amount of cooling area exceeds the structural area (cooling area&gt;structural area). In another embodiment, a ratio of the cooling area to the structural area is less than 1 (cooling area&lt;structural area). In yet another embodiment, a ratio of the cooling area to the structural area is between 1 and 4. Other configurations are also contemplated. 
     In another non-limiting embodiment, the heat transfer devices  290  are disposed inside one or more of the various nodes  292  and branches  294 . This is best depicted in  FIG. 6B . Although shown generically in this embodiment, the heat transfer devices  290  work in the substantially the same manner as the heat transfer devices  90  described above by utilizing an evaporative cooling cycle to transfer thermal energy from the component  50  to the airflow  68  circulated through the open passages  296  of the vascular engineered lattice structure  280 . 
     Although the different non-limiting embodiments are illustrated as having specific components, the embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments. 
     It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure. 
     The foregoing description shall be interpreted as illustrative and not in any limiting sense. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. For these reasons, the following claims should be studied to determine the true scope and content of this disclosure.