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A system and method for configuring a steam turbine to accommodate changing resource conditions, such as may be encountered with geothermal wells. A plurality of sets of nozzle/blade assemblies are provided for installation in a diaphragm structure and on a rotor, respectively. As the condition of s

A system and method for configuring a steam turbine to accommodate changing resource conditions, such as may be encountered with geothermal wells. A plurality of sets of nozzle/blade assemblies are provided for installation in a diaphragm structure and on a rotor, respectively. As the condition of steam provided to the turbine changes, a different set of nozzle/blade assemblies may be installed to maintain a preferred thermodynamic efficiency for the turbine.

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1. A method of providing a nozzle/blade configuration to accommodate different steam conditions from a steam source for supplying steam to the steam turbine, the method comprising: providing a steam turbine including a steam turbine stage comprising: a rotor for detachably supporting a blade assembl

1. A method of providing a nozzle/blade configuration to accommodate different steam conditions from a steam source for supplying steam to the steam turbine, the method comprising: providing a steam turbine including a steam turbine stage comprising: a rotor for detachably supporting a blade assembly;an outer diaphragm ring structure including an inwardly facing diaphragm surface defining a first diaphragm radius;an inner diaphragm ring structure including an outwardly facing diaphragm surface defining a second diaphragm radius;a radial diaphragm gap defined between the inwardly and outwardly facing diaphragm surfaces for receiving a nozzle assembly;providing at least two sets of paired nozzle/blade assemblies for the steam turbine stage, each set of the nozzle/blade assemblies comprising: a nozzle assembly comprising a plurality of nozzles defining a nozzle height for a nozzle passage and a nozzle diameter, the nozzle diameter comprising a radial location of the nozzle passage relative to a rotational axis of the rotor;a blade assembly comprising a plurality of rotor blades, each rotor blade including an airfoil having an airfoil height and an airfoil radial location corresponding to the nozzle height and nozzle diameter, respectively;determining a steam condition at the steam source;selecting a set of the paired nozzle/blade assemblies with reference to the steam condition at the steam source; andinstalling the selected nozzle assembly in the diaphragm gap and installing the selected blade assembly on the rotor to effect an optimized operation of the steam turbine with reference to the steam condition at the steam source. 2. The method as in claim 1, wherein each nozzle comprises: a radially extending nozzle vane;an outer block rigidly affixed to an outer end of the nozzle vane and including structure to support the outer block to the inwardly facing diaphragm surface;an inner block rigidly affixed to an inner end of the nozzle vane and including structure to support the inner block to the outwardly facing diaphragm surface;the nozzle height being defined as a radial distance along the nozzle vane from the inner block to the outer block; andthe nozzle diameter being defined as twice a radial distance from a rotational axis of the rotor to a radially inner edge of the nozzle vane. 3. The method as in claim 2, wherein a dimension for at least one of the nozzle height and the nozzle diameter in each set of the nozzle/blade assemblies is different from a corresponding dimension in any other set of the nozzle/blade assemblies. 4. The method as in claim 2, wherein: the outer block comprises a first outer block surface adjacent to the inwardly facing diaphragm surface and a second outer block surface adjacent to the nozzle vane;the inner block comprising a first inner block surface adjacent to the outwardly facing diaphragm surface and a second inner block surface adjacent to the nozzle vane;a nozzle span defined between the first outer block surface and the first inner block surface, the nozzle span being substantially equal to a diaphragm gap height defined as a difference between the first and second diaphragm radii; andwherein the nozzle span of the nozzles in each set of the nozzle/blade assemblies is the same as the nozzle span of the nozzles in any other set of the nozzle/blade assemblies. 5. The method as in claim 1, wherein each rotor blade further comprises: a root portion;a shank extending between the root portion and the airfoil;the root portion including structure for detachable attachment to the rotor; andthe airfoil height being defined as a radial distance between the shank and a blade tip adjacent to a radially outer end of the rotor blade. 6. The method as in claim 5, wherein a length of the shanks for the rotor blades in each set of the nozzle/blade assemblies is different from the length of the shanks for the rotor blades in any other set of the nozzle/blade assemblies. 7. The method as in claim 5, wherein the airfoil height of the rotor blades is substantially equal to the nozzle height of the nozzles in each set of the nozzle/blade assemblies. 8. The method as in claim 1, wherein the selected set of paired nozzle/blade assemblies comprises a first set of the nozzle/blade assemblies, and including operating the steam turbine for a period of time with the first set of paired nozzle/blade assemblies until a predetermined change in the steam conditions from the steam source is identified, selecting a second set of the nozzle/blade assemblies, and installing the second set of the nozzle/blade assemblies in the diaphragm gap and the rotor in place of the first set of the nozzle/blade assemblies, the second set of the nozzle/blade assemblies comprising: a different nozzle height than the nozzle height of the first set of the nozzle/blade assemblies; anda different airfoil height than the airfoil height of the first set of the nozzle/blade assemblies. 9. The method as in claim 8, wherein the change in steam conditions comprises a decrease in steam temperature from the steam source, and the second set of the nozzle/blade assemblies comprises: a smaller nozzle diameter than the nozzle diameter of the first set of the nozzle/blade assemblies;a larger nozzle height than the nozzle height of the first set of the nozzle/blade assemblies; anda larger airfoil height than the airfoil height of the first set of the nozzle/blade assemblies. 10. A method of changing the efficiency of a steam turbine, the steam turbine comprising: a rotor supporting a first blade assembly comprising a plurality of rotor blades; an outer diaphragm ring structure including an inwardly facing diaphragm surface defining a first diaphragm radius; an inner diaphragm ring structure including an outwardly facing diaphragm surface defining a second diaphragm radius; a radial diaphragm gap defined between the inwardly and outwardly facing diaphragm surfaces; a diaphragm gap height defined as a difference between the first and second diaphragm radii; a first nozzle assembly adjacent to the blade assembly and comprising a plurality of first nozzles located within the diaphragm gap for directing steam onto the rotor blades of the blade assembly; each nozzle comprising a radially extending nozzle vane, an outer block rigidly affixed to an outer end of the nozzle vane, and an inner block rigidly affixed to an inner end of the nozzle vane; the outer block comprising a first outer block surface adjacent to the inwardly facing diaphragm surface and a second outer block surface adjacent to the nozzle vane; the inner block comprising a first inner block surface adjacent to the outwardly facing diaphragm surface and a second inner block surface adjacent to the nozzle vane; a nozzle span defined between the first outer block surface and the first inner block surface, the nozzle span being substantially equal to the diaphragm gap height; a nozzle height defined between the second outer block surface and the second inner block surface; and the outer and inner blocks being detachably supported to the outer and inner diaphragm ring structures, respectively, the method comprising: replacing the first nozzles of first nozzle assembly with second nozzles of a second nozzle assembly wherein the nozzle span of the second nozzles is the same as the nozzle span of the first nozzles, and the nozzle height of the second nozzles is different from the nozzle height of the first nozzles to effect a change in the efficiency of the steam turbine. 11. The method as in claim 10, including outer and inner block heights defined between the first and second surfaces of the respective outer and inner blocks, wherein at least one of the outer and inner block heights of the second nozzles is different from a corresponding one of the outer and inner block heights of the first nozzles. 12. The method as in claim 11, wherein both the outer block height and the inner block height of the second nozzles are different from the respective outer and inner block heights of the first nozzles. 13. The method as in claim 10, wherein the rotor blades comprise a root portion, an airfoil and a shank extending between the root portion and the airfoil, the root portion including structure for detachable attachment to the rotor, and the airfoil defining an airfoil height between the shank and a blade tip, and including: replacing the first blade assembly with a second blade assembly;wherein the airfoil height of the second blade assembly is different from the airfoil height of the first blade assembly. 14. The method as in claim 13, wherein the airfoil heights of the first and second blade assemblies are substantially equal to the respective nozzle heights of the first and second nozzles. 15. The method as in claim 13, wherein a radial location of the root portion of the rotor blades of the second blade assembly is the same as a radial location of the root portion of the rotor blades of the first blade assembly. 16. A system for providing a nozzle/blade configuration to accommodate different steam conditions from a steam source for supplying steam to the steam turbine, the steam turbine including a steam turbine stage comprising: a rotor for detachably supporting a blade assembly; an outer diaphragm ring structure including an inwardly facing diaphragm surface defining a first diaphragm radius; an inner diaphragm ring structure including an outwardly facing diaphragm surface defining a second diaphragm radius; a radial diaphragm gap defined between the inwardly and outwardly facing diaphragm surfaces for receiving a nozzle assembly; and a diaphragm gap height defined as a difference between the first and second diaphragm radii, the system comprising: at least two sets of paired nozzle/blade assemblies for the steam turbine stage, each set of the nozzle/blade assemblies comprising: a nozzle assembly comprising a plurality nozzles for installation in the diaphragm gap, each nozzle comprising an outer block comprising a first outer block surface for engagement adjacent to the inwardly facing diaphragm surface and a second outer block surface adjacent to the nozzle vane, an inner block comprising a first inner block surface for engagement adjacent to the outwardly facing diaphragm surface and a second inner block surface adjacent to the nozzle vane, a nozzle span defined between the first outer block surface and the first inner block surface, and each nozzle defining a nozzle height between the second outer block surface and the second inner block surface; anda blade assembly comprising plurality of rotor blades for attachment to the rotor, each rotor blade including an airfoil having an airfoil height corresponding to the nozzle height of the nozzles;wherein the nozzle span of the nozzles in each set of the nozzle/blade assemblies is substantially equal to the diaphragm gap height, and the nozzle height in each set of the nozzle/blade assemblies is different from the nozzle height in any other set of the nozzle/blade assemblies. 17. The system as in claim 16, wherein the airfoil height of the rotor blades in each set of the nozzle/blade assemblies is different from the airfoil height of the rotor blades in any other set of the nozzle/blade assemblies. 18. The system as in claim 17, wherein each rotor blade comprises: a root portion;a shank extending between the root portion and the airfoil;the root portion including structure for detachable attachment to the rotor;the airfoil height being defined as a radial distance between the shank and a blade tip adjacent to a radially outer end of the rotor blade; andwherein a length of the shanks for the rotor blades in each set of the nozzle/blade assemblies is different from the length of the shanks for the rotor blades in any other set of the nozzle/blade assemblies.