AIRFOIL SHAPE FOR A TURBINE NOZZLE

Abstract

The third stage nozzle has an airfoil profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein X and Y values are in inches and define airfoil profile sections at each distance Z and Z is a non-dimensional value from 0 to 1 convertible to Z distances in inches by multiplying the Z values of Table I by a height of the airfoil in inches. The profile sections at the Z distances are joined smoothly with one another to form a complete airfoil shape. The X and Y distances may be scalable to provide a scaled-up or scaled-down airfoil for the nozzle. The nominal airfoil given by the X, Y and Z distances lies within an envelope of ±0.100 inches.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to an airfoil for a nozzle stage of a gas turbine and particularly relates to an airfoil for a third stage nozzle of a gas turbine.

[0002] Many specific requirements must be met for each stage of the hot gas path section of a gas turbine in order to meet design goals, including overall improved efficiency and loading. Particularly, the third stage of the turbine section must meet efficiency, heat load, life, throat area and vectoring requirements to meet that goal.

BRIEF DESCRIPTION OF THE INVENTION

[0003] In accordance with a preferred embodiment of the present invention, there is provided an airfoil shape for a nozzle stage of a gas turbine, preferably the third stage nozzle, that enhances the performance of the gas turbine. The airfoil shape hereof improves the interaction between various stages in the turbine, affords improved aerodynamic efficiency through the third stage and improves the third stage blade loading. Thus, the profile of each second stage nozzle airfoil which in part defines the hot gas path annulus about the nozzle stage meets the requirements for improved stage efficiency, as well as parts life and manufacturability.

[0004] In a preferred embodiment according to the present invention, there is provided a turbine nozzle including an airfoil having an airfoil shape, the airfoil having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 1 convertible to Z distances in inches by multiplying the Z values of Table I by a height of the airfoil in inches, and wherein the X and Y values are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape.

[0005] In a further preferred embodiment according to the present invention, there is provided a turbine nozzle including an airfoil having an uncoated nominal airfoil profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 1 convertible to Z distances in inches by multiplying the Z values of Table I by a height of the airfoil in inches, and wherein the X and Y values are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape, the X, Y and Z distances being scalable as a function of the same constant or number to provide a scaled-up or scaled-down airfoil.

[0006] In a further preferred embodiment according to the present invention, there is provided a turbine comprising a turbine stage having a plurality of nozzles, each of the nozzles including an airfoil having an airfoil shape, the airfoil having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 1 convertible to Z distances in inches by multiplying the Z values of Table I by a height of the airfoil in inches, and wherein X and Y values are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. 1 is a schematic representation of a hot gas path through a gas turbine and which illustrates a third stage nozzle airfoil according to a preferred embodiment of the present invention;

[0008] FIG. 2 is a perspective view of three airfoil blades forming portions of the third stage nozzles of the turbine according to the present invention, and including portions of the inner and outer nozzle bands, all as viewed from the trailing edges;

[0009] FIG. 3 is a view similar to FIG. 2 as viewed from the leading edges of the blades;

[0010] FIG. 4 is a side elevational view of the third stage nozzle airfoil; and

[0011] FIG. 5 is a generalized cross-sectional view of the airfoil hereof taken at a location through the third stage nozzle airfoil.

DETAILED DESCRIPTION OF THE INVENTION

[0012] Referring now to the drawings, particularly to FIG. 1, there is illustrated a multi-stage turbine section, generally designated 10, for a gas turbine 12 including a plurality of turbine stages. Three stages are illustrated. For example, the first stage comprises a plurality of circumferentially spaced nozzle or blades 14 and buckets 16, the nozzles being circumferentially spaced one from the other and fixed about the axis of the turbine rotor 15. The buckets 16, of course, are mounted on and circumferentially spaced about the rotor 15. A second stage of the turbine 12 is also illustrated, including a plurality of circumferentially spaced nozzles 18 and a plurality of buckets 20 mounted on the rotor 15. A third stage is also illustrated, including a plurality of circumferentially spaced nozzles 22 and buckets 24. It will be appreciated that the nozzles and buckets lie in the turbine's hot gas path indicated by the arrow 26.

[0013] Referring to FIGS. 2 and 3, it will be appreciated that the nozzle stages, for example, the third stage nozzle 22, extend generally radially between inner and outer bands 28 and 30, respectively, which also in part define the hot gas path 26 through turbine 12. Typically, the nozzles 22 are provided as either singlets, doublets or triplets with associated inner and outer bands which are secured together to form a circumferential array of nozzles about the axis of rotation of the rotor. The nozzles 22 are preferably provided in triplets as illustrated. It will be appreciated that each nozzle 22 is in the shape of an airfoil or airfoil-shaped blade 32, as illustrated in FIG. 5. That is, each nozzle 22 has a profile at any cross-section between the inner and outer bands 28 and 30, respectively, in the shape of an airfoil 32. In this preferred embodiment, there are sixty-six (66) nozzle blades in the shape of airfoils 32 which, together with the inner and outer bands 28 and 30, constitute the nozzles 22 of the third stage of the turbine.

[0014] To define the airfoil shape of the third stage nozzle airfoil which optimizes the guided hot gas turning and overall efficiency of the turbine, there are a unique set or loci of points in space that meet the stage requirements and can be manufactured. This unique loci of points meets the requirements for nozzle loading and stage efficiency and are arrived at by iteration between aerodynamics and nozzle mechanical loading, enabling the turbine to run in an efficient, safe and smooth manner. The loci which defines the nozzle airfoil profile comprises a set of 600 points. A Cartesian coordinate system of X, Y and Z values given in Table I below defines the profile of each nozzle airfoil. The values for the X and Y coordinates are set forth in inches in Table I, although other units of dimensions may be used when the values are appropriately converted. The Z values set forth in Table I are non-dimensional values from 0 to 1. To convert each Z value to a Z distance in inches, the non-dimensional Z values given in Table I are multiplied by a constant in inches, e.g., the height of the nozzle airfoil. The airfoil height H may be measured from a point at the intersection of the trailing edge 38 of the nozzle 22 and the outer band 30 along a radius which intersects the inner band aft of the trailing edge 38 at 37 (FIG. 4) and is about 8.125 inches. The preferred distance D (FIG. 4) from the point of intersection 35 of each nozzle of the third stage from the rotor axis 34 is 28.930 inches. The coordinate system has orthogonally related X, Y and Z axes with the Z axis extending perpendicular to a plane normal to a plane containing the X and Y values. The Y axis lies parallel to the turbine rotor centerline, i.e., the rotary axis 34 and is positive forward to aft. The Z direction is negative in a radial inward direction and the X direction is negative in a tangential counterclockwise direction as viewed in the aft direction.

[0015] By defining X and Y coordinate values at selective locations in a Z direction normal to the X, Y plane, the profile of the airfoil at each Z distance can be ascertained. By connecting the X and Y values with smooth continuing arcs, each profile section at each distance Z is fixed. The surface profiles of the various surface locations between the distances Z are determined by smoothly connecting the adjacent cross-sections to one another to form the airfoil. The values set forth in Table I represent the airfoil profiles at ambient, non-operating or non-hot conditions and are for an uncoated airfoil. The sign convention assigns a positive value to Z values and positive and negative values for X and Y coordinates as typically used in the Cartesian coordinate system.

[0016] The Table I values are generated and shown to three decimal places for determining the profile of the nozzle airfoil. There are typical manufacturing tolerances, as well as coatings, which must be accounted for in the actual profile of the airfoil. Accordingly, the values for the profile given in Table I are for a nominal airfoil. Thus, the actual profile of the nozzle airfoil may lie in a range of variations between measured points on an airfoil surface and their ideal position as listed in Table I. The design is robust to this variation to the extent that mechanical and aerodynamic functions are not impaired. It will be therefore be appreciated that ± typical manufacturing tolerances, i.e., ± values, including any coating thicknesses, are additive to the X and Y values given in Table I below. Accordingly, a distance of ±0.100 inches in a direction normal to any surface location along the airfoil profile defines an airfoil profile envelope for this particular third stage nozzle airfoil.

[0017] The coordinate values are given below in Table I for the preferred nominal profile envelope:

	TABLE I
	POINTS	X	Y	Z′
	1	0.176	0.469	0.535
	2	0.534	1.787	0.845
	3	1.063	0.813	1.000
	4	0.195	0.433	0.690
	5	0.652	1.635	0.690
	6	0.966	0.790	0.690
	7	0.859	0.193	0.690
	8	0.894	0.288	0.690
	9	0.966	0.688	0.690
	10	0.647	−0.152	0.690
	11	0.038	1.331	0.690
	12	0.167	0.839	0.690
	13	0.855	−0.055	0.845
	14	0.919	0.710	0.535
	15	0.854	1.313	1.000
	16	0.250	−0.030	0.845
	17	0.674	1.584	1.000
	18	0.995	1.019	1.000
	19	0.803	0.233	0.535
	20	0.331	−0.232	0.535
	21	0.172	0.370	0.535
	22	0.534	1.751	1.000
	23	0.273	0.449	1.000
	24	0.076	1.182	1.000
	25	0.373	−0.196	1.000
	26	0.214	0.283	0.845
	27	0.118	1.011	0.845
	28	0.901	0.040	0.845
	29	0.193	0.535	0.690
	30	0.413	−0.296	1.000
	31	0.064	1.244	0.535
	32	0.798	1.406	1.000
	33	0.272	−0.133	0.845
	34	0.765	1.466	0.690
	35	0.944	0.992	0.690
	36	0.922	0.386	0.690
	37	0.573	−0.223	0.690
	38	−0.047	1.516	0.690
	39	0.202	0.026	0.690
	40	0.196	0.332	0.690
	41	0.939	0.138	0.845
	42	0.509	−0.156	0.535
	43	0.158	0.862	0.535
	44	0.620	1.628	0.535
	45	0.147	0.977	1.000
	46	0.955	1.069	0.845
	47	0.991	0.341	0.845
	48	0.656	−0.296	0.845
	49	0.235	0.074	0.845
	50	0.158	0.805	0.845
	51	1.122	0.275	1.000
	52	0.731	1.542	0.845
	53	1.109	0.167	1.000
	54	0.307	−0.231	0.845
	55	0.159	0.173	0.535
	56	0.178	0.873	1.000
	57	0.893	1.189	0.690
	58	0.958	0.586	0.690
	59	0.711	−0.074	0.690
	60	0.105	1.138	0.690
	61	0.173	0.701	0.845
	62	0.521	1.791	0.690
	63	0.121	1.056	0.535
	64	0.884	1.267	0.845
	65	1.006	0.445	0.845
	66	0.160	−0.024	0.535
	67	0.029	1.336	0.535
	68	0.738	1.496	1.000
	69	0.799	−0.144	0.845
	70	0.481	−0.380	1.000
	71	1.086	0.061	1.000
	72	1.120	0.492	1.000
	73	0.206	0.768	1.000
	74	−0.010	1.411	0.845
	75	0.242	−0.173	0.690
	76	0.980	0.967	0.845
	77	0.759	0.145	0.535
	78	0.495	1.780	0.535
	79	0.185	0.597	0.845
	80	0.306	0.234	1.000
	81	0.142	0.959	0.535
	82	0.588	1.714	0.690
	83	0.488	−0.278	0.690
	84	0.198	0.128	0.690
	85	0.179	0.738	0.690
	86	0.677	1.548	0.535
	87	0.462	−0.360	0.845
	88	−0.054	1.506	0.845
	89	0.095	1.151	0.535
	90	0.606	1.669	1.000
	91	0.035	1.283	1.000
	92	1.011	0.760	0.845
	93	0.350	−0.089	1.000
	94	0.872	−0.312	1.000
	95	1.089	0.707	1.000
	96	0.910	0.612	0.535
	97	0.559	1.706	0.535
	98	0.196	0.492	0.845
	99	0.335	0.018	1.000
	100	0.788	1.453	0.845
	101	−0.110	1.575	1.000
	102	0.711	1.552	0.690
	103	0.958	0.891	0.690
	104	0.944	0.486	0.690
	105	0.389	−0.297	0.690
	106	0.253	0.556	1.000
	107	0.074	1.235	0.690
	108	0.151	0.940	0.690
	109	0.906	1.217	1.000
	110	1.014	0.550	0.845
	111	0.205	0.388	0.845
	112	0.953	1.119	1.000
	113	0.841	0.325	0.535
	114	−0.104	1.600	0.535
	115	0.291	0.341	1.000
	116	0.113	1.080	1.000
	117	0.670	1.627	0.845
	118	0.969	0.238	0.845
	119	0.565	−0.348	0.845
	120	0.224	0.178	0.845
	121	0.140	0.909	0.845
	122	−0.102	1.600	0.845
	123	0.240	−0.199	0.535
	124	−0.095	1.605	0.690
	125	0.166	0.272	0.535
	126	0.029	1.313	0.845
	127	0.786	−0.377	1.000
	128	1.016	0.655	0.845
	129	0.813	1.376	0.690
	130	0.922	1.091	0.690
	131	0.768	0.011	0.690
	132	0.298	−0.256	0.690
	133	0.214	−0.075	0.690
	134	0.196	0.230	0.690
	135	0.175	0.666	0.535
	136	0.733	−0.225	0.845
	137	0.871	0.419	0.535
	138	0.649	−0.018	0.535
	139	0.583	−0.091	0.535
	140	0.155	0.075	0.535
	141	0.169	0.764	0.535
	142	0.923	1.169	0.845
	143	0.321	0.126	1.000
	144	0.579	−0.425	1.000
	145	1.032	0.917	1.000
	146	1.125	0.383	1.000
	147	0.063	1.214	0.845
	148	0.686	−0.420	1.000
	149	−0.056	1.514	0.535
	150	0.894	0.514	0.535
	151	0.604	1.709	0.845
	152	1.005	−0.141	1.000
	153	0.856	1.284	0.690
	154	0.818	0.100	0.690
	155	0.130	1.040	0.690
	156	0.188	0.637	0.690
	157	0.426	−0.209	0.535
	158	−0.002	1.424	0.690
	159	0.093	1.113	0.845
	160	0.368	−0.316	0.845
	161	−0.012	1.426	0.535
	162	1.052	−0.042	1.000
	163	0.999	0.864	0.845
	164	0.707	0.061	0.535
	165	0.184	−0.119	0.535
	166	0.178	0.567	0.535
	167	0.231	0.662	1.000
	168	−0.010	1.382	1.000
	169	1.108	0.600	1.000
	170	0.946	−0.231	1.000
	171	−0.058	1.480	1.000
	172	0.839	1.361	0.845
	173	−1.749	3.192	1.000
	174	−1.775	3.137	0.535
	175	0.220	2.051	1.000
	176	−0.532	2.140	0.535
	177	−0.464	2.090	0.690
	178	−0.266	1.858	0.690
	179	−1.234	2.738	1.000
	180	−0.700	2.326	0.845
	181	−1.914	3.150	0.845
	182	−0.293	2.430	0.845
	183	−1.311	2.975	0.845
	184	−1.454	3.024	0.690
	185	−1.085	2.852	0.690
	186	−0.791	2.681	0.535
	187	−0.531	2.540	0.535
	188	−1.234	2.899	0.535
	189	−1.058	2.586	0.535
	190	−1.958	3.212	0.535
	191	−1.866	3.175	0.535
	192	−0.148	1.692	0.690
	193	−0.760	2.370	0.690
	194	−1.468	2.860	0.535
	195	0.130	2.112	0.535
	196	−2.050	3.319	1.000
	197	−1.354	3.010	1.000
	198	−0.679	2.659	1.000
	199	−0.037	2.252	1.000
	200	−0.288	1.848	1.000
	201	−0.805	2.404	1.000
	202	−1.414	2.860	1.000
	203	−2.069	3.246	1.000
	204	0.136	2.120	1.000
	205	−1.145	2.675	1.000
	206	−0.382	2.485	0.845
	207	0.283	1.987	0.535
	208	−0.422	2.019	1.000
	209	−0.967	2.770	0.535
	210	−1.681	3.005	0.690
	211	−1.406	3.020	0.845
	212	−0.329	1.938	0.690
	213	−0.942	2.527	0.845
	214	−0.157	1.684	0.535
	215	0.051	2.171	0.535
	216	−1.693	3.149	0.845
	217	−0.108	2.306	0.690
	218	−1.828	3.185	0.690
	219	−0.902	2.761	0.690
	220	0.376	1.934	0.690
	221	−0.704	2.635	0.535
	222	−0.901	2.467	0.535
	223	−1.164	2.679	0.690
	224	−1.958	3.212	0.535
	225	−0.211	1.779	0.845
	226	−0.397	1.997	0.535
	227	−1.731	3.047	0.845
	228	−0.404	2.028	0.845
	229	−1.550	2.940	0.845
	230	−1.551	3.103	1.000
	231	−0.463	2.069	0.535
	232	−0.110	2.284	0.535
	233	0.057	2.198	0.845
	234	−0.645	2.257	1.000
	235	−0.870	2.764	1.000
	236	−0.860	2.462	0.845
	237	−1.879	3.141	1.000
	238	−1.948	3.153	0.690
	239	0.306	2.004	0.845
	240	−1.081	2.620	0.690
	241	−2.017	3.261	0.690
	242	−1.886	3.231	0.845
	243	−0.193	2.362	0.690
	244	−1.361	2.982	0.690
	245	−0.722	2.667	0.690
	246	0.222	2.067	0.690
	247	−1.056	2.814	0.535
	248	−1.144	2.857	0.535
	249	−1.684	3.099	0.535
	250	−0.749	2.341	0.535
	251	−1.301	2.754	0.535
	252	−1.894	3.107	0.535
	253	−0.395	2.015	0.690
	254	−0.564	2.590	0.845
	255	0.427	1.852	0.535
	256	−0.272	1.865	0.845
	257	−0.779	2.395	0.845
	258	−0.332	1.922	0.535
	259	−0.276	2.390	0.535
	260	−0.748	2.691	0.845
	261	−0.115	2.317	0.845
	262	0.461	1.862	0.845
	263	−1.058	2.610	1.000
	264	−1.691	3.032	1.000
	265	−1.949	3.277	1.000
	266	−0.205	1.776	0.690
	267	0.225	2.071	0.845
	268	−1.637	2.962	0.535
	269	−1.552	2.911	0.535
	270	−0.125	2.315	1.000
	271	−1.769	3.055	0.690
	272	0.385	1.935	0.845
	273	−0.361	2.441	0.535
	274	−1.062	2.865	1.000
	275	−1.248	2.736	0.690
	276	−0.999	2.560	0.690
	277	−0.279	2.416	0.690
	278	−0.367	2.468	0.690
	279	−1.547	3.065	0.690
	280	−0.454	2.520	0.690
	281	−0.879	2.726	0.535
	282	−0.617	2.588	0.535
	283	−1.503	3.021	0.535
	284	−1.138	2.643	0.535
	285	−1.722	3.011	0.535
	286	−0.838	2.435	0.690
	287	0.142	2.135	0.845
	288	−0.494	2.101	1.000
	289	−0.154	1.691	0.845
	290	−0.622	2.255	0.845
	291	−1.197	2.713	0.845
	292	−1.822	3.099	0.845
	293	−1.256	2.963	1.000
	294	−0.585	2.605	1.000
	295	0.051	2.187	1.000
	296	−0.934	2.789	0.845
	297	−0.353	1.935	1.000
	298	−0.888	2.475	1.000
	299	−2.166	3.296	1.000
	300	−0.212	1.765	0.535
	301	−1.461	2.885	0.845
	302	−1.284	2.771	0.845
	303	−1.159	2.914	1.000
	304	−2.038	3.201	0.690
	305	−1.216	2.930	0.845
	306	0.142	2.130	0.690
	307	−1.984	3.271	0.845
	308	−0.993	2.807	0.690
	309	0.300	2.002	0.690
	310	−0.446	2.491	0.535
	311	−0.675	2.276	0.535
	312	−1.413	2.981	0.535
	313	−0.535	2.163	0.690
	314	−0.608	2.234	0.690
	315	−1.858	3.105	0.690
	316	−0.306	2.435	1.000
	317	−0.683	2.303	0.690
	318	−0.724	2.332	1.000
	319	−1.372	2.829	0.845
	320	−0.841	2.741	0.845
	321	−1.026	2.590	0.845
	322	−1.640	2.994	0.845
	323	−2.150	3.360	1.000
	324	−0.774	2.712	1.000
	325	−0.029	2.228	0.535
	326	0.460	1.830	1.000
	327	−0.225	1.760	1.000
	328	−1.323	2.800	1.000
	329	−1.974	3.194	1.000
	330	−0.547	2.182	0.845
	331	−0.166	1.669	1.000
	332	−1.505	2.919	1.000
	333	−2.081	3.310	0.845
	334	−0.398	2.493	1.000
	335	−1.333	2.792	0.690
	336	−1.419	2.847	0.690
	337	−1.790	3.191	0.845
	338	0.060	2.191	0.690
	339	−1.177	2.896	0.690
	340	−1.501	3.064	0.845
	341	−0.812	2.715	0.690
	342	0.450	1.864	0.690
	343	−1.323	2.940	0.535
	344	−0.824	2.405	0.535
	345	−1.384	2.808	0.535
	346	−1.981	3.153	0.535
	347	−2.017	3.261	0.690
	348	−1.593	2.953	0.690
	349	−0.918	2.498	0.690
	350	−2.081	3.310	0.845
	351	−0.474	2.106	0.845
	352	0.382	1.906	1.000
	353	0.207	2.050	0.535
	354	−0.473	2.538	0.845
	355	−0.336	1.948	0.845
	356	−1.650	3.148	1.000
	357	−0.966	2.815	1.000
	358	−0.193	2.338	0.535
	359	0.356	1.921	0.535
	360	−0.656	2.641	0.845
	361	−0.028	2.258	0.845
	362	−0.215	2.376	1.000
	363	−1.784	3.087	1.000
	364	−2.100	3.248	0.845
	365	−0.568	2.180	1.000
	366	−1.028	2.837	0.845
	367	−0.979	2.527	0.535
	368	−1.452	3.057	1.000
	369	−1.506	2.901	0.690
	370	−1.597	3.107	0.845
	371	−1.922	3.223	0.690
	372	−0.023	2.249	0.690
	373	−1.269	2.939	0.690
	374	−1.640	3.106	0.690
	375	−0.632	2.619	0.690
	376	−1.734	3.146	0.690
	377	0.302	1.980	1.000
	378	−0.602	2.209	0.535
	379	−1.593	3.060	0.535
	380	−1.219	2.699	0.535
	381	−1.808	3.059	0.535
	382	−0.543	2.570	0.690
	383	−2.006	3.200	0.845
	384	−0.204	2.374	0.845
	385	−1.849	3.235	1.000
	386	−0.271	1.845	0.535
	387	−0.491	2.550	1.000
	388	−0.972	2.543	1.000
	389	−1.598	2.976	1.000
	390	−2.150	3.360	1.000
	391	−1.111	2.652	0.845
	392	−1.122	2.884	0.845
	393	−0.135	0.100	0.000
	394	0.026	0.318	0.268
	395	0.502	0.272	0.000
	396	−0.149	1.128	0.000
	397	0.795	0.643	0.268
	398	0.015	0.964	0.268
	399	0.546	0.346	0.000
	400	0.470	1.671	0.268
	401	0.315	−0.099	0.268
	402	0.649	0.207	0.268
	403	0.035	0.688	0.268
	404	0.000	1.055	0.268
	405	0.627	1.443	0.268
	406	0.780	0.551	0.268
	407	0.392	0.139	0.000
	408	0.423	1.568	0.000
	409	0.584	0.424	0.000
	410	−0.174	0.353	0.000
	411	0.817	1.287	0.535
	412	0.591	1.267	0.000
	413	0.410	1.741	0.268
	414	0.000	0.000	0.000
	415	0.473	−0.005	0.268
	416	0.540	0.059	0.268
	417	0.020	0.133	0.268
	418	−0.041	1.236	0.268
	419	0.758	0.462	0.268
	420	0.851	1.195	0.535
	421	0.776	1.377	0.535
	422	0.556	1.346	0.000
	423	0.516	1.422	0.000
	424	−0.237	1.462	0.000
	425	0.708	1.277	0.268
	426	0.314	1.702	0.000
	427	0.619	1.185	0.000
	428	0.638	0.588	0.000
	429	0.326	0.084	0.000
	430	−0.165	0.181	0.000
	431	−0.134	0.783	0.000
	432	−0.208	1.380	0.000
	433	0.693	0.289	0.268
	434	0.065	−0.043	0.268
	435	0.036	0.595	0.268
	436	−0.099	1.411	0.268
	437	0.032	0.780	0.268
	438	0.740	1.190	0.268
	439	0.729	1.464	0.535
	440	0.901	1.004	0.535
	441	−0.157	0.525	0.000
	442	0.579	1.522	0.268
	443	0.171	0.009	0.000
	444	0.804	0.827	0.268
	445	0.451	0.202	0.000
	446	−0.147	0.611	0.000
	447	−0.164	1.213	0.000
	448	−0.068	1.324	0.268
	449	0.729	0.374	0.268
	450	0.030	0.041	0.268
	451	0.766	1.101	0.268
	452	0.225	−0.118	0.268
	453	−0.175	1.580	0.268
	454	0.251	0.040	0.000
	455	0.666	0.758	0.000
	456	0.472	1.496	0.000
	457	0.667	0.931	0.000
	458	0.086	−0.006	0.000
	459	−0.167	0.439	0.000
	460	−0.139	1.042	0.000
	461	0.786	1.011	0.268
	462	0.670	1.361	0.268
	463	0.598	0.130	0.268
	464	−0.018	1.146	0.268
	465	0.670	0.844	0.000
	466	0.798	0.919	0.268
	467	−0.132	0.870	0.000
	468	0.370	1.636	0.000
	469	0.642	1.102	0.000
	470	0.614	0.505	0.000
	471	−0.078	0.036	0.000
	472	−0.134	0.956	0.000
	473	−0.175	0.267	0.000
	474	0.022	0.226	0.268
	475	0.879	1.101	0.535
	476	0.254	1.765	0.000
	477	0.655	0.672	0.000
	478	0.658	1.017	0.000
	479	−0.139	0.697	0.000
	480	−0.184	1.297	0.000
	481	0.526	1.598	0.268
	482	0.398	−0.059	0.268
	483	−0.269	1.542	0.000
	484	0.803	0.735	0.268
	485	0.134	−0.103	0.268
	486	0.034	0.503	0.268
	487	0.030	0.410	0.268
	488	−0.135	1.496	0.268
	489	0.025	0.872	0.268
	490	0.914	0.907	0.535
	491	0.920	0.808	0.535
	492	−0.598	2.047	0.000
	493	−1.532	2.809	0.000
	494	−0.871	2.561	0.000
	495	−0.355	2.245	0.000
	496	−1.402	2.851	0.000
	497	−0.655	2.111	0.000
	498	−0.003	2.110	0.268
	499	−1.112	2.584	0.268
	500	−1.656	2.934	0.268
	501	−0.615	2.170	0.268
	502	−0.218	1.661	0.268
	503	−0.306	1.620	0.000
	504	−1.246	2.616	0.000
	505	0.129	1.883	0.000
	506	−1.388	2.715	0.000
	507	−1.790	3.041	0.000
	508	−0.946	2.604	0.000
	509	−0.501	2.339	0.000
	510	−0.004	1.994	0.000
	511	−0.078	2.164	0.268
	512	−0.964	2.473	0.268
	513	−1.362	2.896	0.268
	514	−0.787	2.600	0.268
	515	−0.309	2.319	0.268
	516	−0.820	2.357	0.268
	517	−1.498	2.838	0.268
	518	−1.790	3.041	0.000
	519	−0.317	1.818	0.268
	520	−0.626	2.509	0.268
	521	−1.826	2.992	0.000
	522	−1.445	2.936	0.268
	523	−0.891	2.416	0.268
	524	−0.391	1.771	0.000
	525	−0.777	2.234	0.000
	526	−1.753	2.946	0.000
	527	−0.648	2.429	0.000
	528	−1.529	2.975	0.268
	529	−0.154	2.217	0.268
	530	−1.341	2.739	0.268
	531	−1.896	3.072	0.268
	532	−0.428	1.965	0.268
	533	−0.231	2.269	0.268
	534	−1.557	2.929	0.000
	535	−1.249	2.771	0.000
	536	−1.106	2.514	0.000
	537	−0.283	2.197	0.000
	538	0.193	1.825	0.000
	539	0.070	2.054	0.268
	540	−1.697	3.052	0.268
	541	−1.114	2.773	0.268
	542	−1.188	2.637	0.268
	543	−1.736	2.980	0.268
	544	−1.634	2.967	0.000
	545	−0.750	2.297	0.268
	546	−0.550	2.104	0.268
	547	−0.868	2.644	0.268
	548	−0.542	1.981	0.000
	549	−0.971	2.406	0.000
	550	−1.460	2.762	0.000
	551	−0.797	2.517	0.000
	552	−0.387	2.368	0.268
	553	−0.905	2.350	0.000
	554	−1.279	2.855	0.268
	555	0.281	1.873	0.268
	556	−1.037	2.529	0.268
	557	−1.577	2.886	0.268
	558	−1.712	3.005	0.000
	559	−0.950	2.687	0.268
	560	−0.681	2.234	0.268
	561	−0.266	1.741	0.268
	562	−0.466	2.416	0.268
	563	−1.782	3.090	0.268
	564	−0.438	1.843	0.000
	565	−0.840	2.293	0.000
	566	−1.316	2.666	0.000
	567	−0.574	2.384	0.000
	568	−0.072	2.047	0.000
	569	−0.489	1.913	0.000
	570	0.212	1.936	0.268
	571	−0.706	2.555	0.268
	572	−0.142	2.098	0.000
	573	−1.022	2.646	0.000
	574	−0.546	2.463	0.268
	575	−1.419	2.789	0.268
	576	−1.867	3.127	0.268
	577	−1.326	2.811	0.000
	578	−1.867	3.127	0.268
	579	−1.097	2.688	0.000
	580	−0.371	1.893	0.268
	581	−1.038	2.461	0.000
	582	−1.173	2.730	0.000
	583	−1.605	2.856	0.000
	584	−0.347	1.696	0.000
	585	0.142	1.996	0.268
	586	−1.176	2.565	0.000
	587	−1.679	2.901	0.000
	588	0.063	1.940	0.000
	589	−0.212	2.148	0.000
	590	−0.722	2.474	0.000
	591	0.347	1.809	0.268
	592	−1.613	3.014	0.268
	593	−1.032	2.730	0.268
	594	−0.715	2.174	0.000
	595	−1.264	2.689	0.268
	596	−1.816	3.026	0.268
	597	−1.479	2.890	0.000
	598	−0.488	2.036	0.268
	599	−0.428	2.292	0.000
	600	−1.196	2.814	0.268

[0018] It will also be appreciated that the airfoil profile disclosed in the above table may be scaled up or down geometrically for use in other similar turbine designs. Consequently, the coordinate values set forth in Table I may be scaled upwardly or downwardly such that the airfoil section shape remains unchanged. A scaled version of the coordinates in Table I is represented by X, Y and Z distances in inches, multiplied or divided by a constant number.

[0019] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A turbine nozzle including an airfoil having an airfoil shape, said airfoil having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 1 convertible to Z distances in inches by multiplying the Z values of Table I by a height of the airfoil in inches, and wherein the X and Y values are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape.

2. A turbine nozzle according to claim 1 forming part of a third stage of a turbine.

3. A turbine nozzle according to claim 1 wherein said airfoil shape lies in an envelope within +0.100 inches in a direction normal to any airfoil surface location therealong.

4. A turbine nozzle including an airfoil having an uncoated nominal airfoil profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 1 convertible to Z distances in inches by multiplying the Z values of Table I by a height of the airfoil in inches, and wherein the X and Y values are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape, the X, Y and Z distances being scalable as a function of the same constant or number to provide a scaled-up or scaled-down airfoil.

5. A turbine nozzle according to claim 4 forming part of a third stage of a turbine.

6. A turbine nozzle according to claim 1 wherein each said airfoil shape lies in an envelope within ±0.100 inches in a direction normal to any airfoil surface location therealong.

7. A turbine comprising a turbine stage having a plurality of nozzles, each of said nozzles including an airfoil having an airfoil shape, said airfoil having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 1 convertible to Z distances in inches by multiplying the Z values of Table I by a height of the airfoil in inches, and wherein X and Y values are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape.

8. A turbine according to claim 7 wherein the turbine nozzles comprises part of a third stage of the turbine.

9. A turbine according to claim 8 wherein the turbine stage has 66 nozzles and the coordinate value Y extends parallel to an axis of rotation of the turbine.

10. A turbine according to claim 7 wherein each said airfoil shape lies in an envelope within ±0.100 inches in a direction normal to any airfoil surface location therealong.