Continuous-flow machine with at least one guide vane ring

{
  "publication_number": "US9506360B2",
  "country": "US",
  "kind": "B2",
  "title": "Continuous-flow machine with at least one guide vane ring",
  "abstract": "A continuous-flow machine, especially an axial compressor, having at least one guide vane ring that includes at least one row of adjustable guide vanes, whereby each guide vane is tapered relative to its vane body in the direction of its longitudinal axis as seen in a side view of the guide vane. In order to increase the stability of the flow in the continuous-flow machine, each row of guide vanes comprises first guide vanes and second guide vanes, whereby, as seen in a combined side view of a first guide vane and of a second guide vane, each first guide vane is tapered along its vane body in the lengthwise direction, and each second guide vane is tapered in the opposite direction.",
  "claims": [
    "1. A continuous-flow machine comprising: at least one guide vane ring, the guide vane ring defining radial, circumferential and axial directions, the guide vane ring including at least one row of a plurality of guide vanes spaced in the circumferential direction, each guide vane of the plurality of guide vanes having a vane body with a longitudinal axis in the radial direction between a base and a tip, the plurality of guide vanes including first guide vanes and second guide vanes, each first guide vane being tapered along the longitudinal axis so that the vane body becomes narrower at the tip than the base and each second guide vane being tapered in an opposite direction along the longitudinal axis so that the vane body becomes wider at the tip than the base.",
    "2. The continuous-flow machine as recited in claim 1, wherein one of the first guide vanes and one of the second guide vanes form a unit, and a plurality of the units are evenly distributed in the circumferential direction whereby distances between adjacent one of said first and one of said second guide vanes are different from each other.",
    "3. The continuous-flow machine as recited in claim 1 wherein the first and second guide vanes are in a same position in the axial direction of the continuous-flow machine.",
    "4. The continuous-flow machine as recited in claim 1, wherein the second guide vanes are arranged offset in the axial direction with respect to the first guide vanes.",
    "5. The continuous-flow machine as recited in claim 1 wherein the first guide vanes and the second guide vanes have an overlapping area in the axial direction.",
    "6. The continuous-flow machine as recited in claim 1, wherein each of the first guide vanes taper due to a varying shape of rear edge of the first guide vane and each of the second guide vanes taper due to a further varying shape of the second guide vane.",
    "7. The continuous-flow machine as recited in claim 1, wherein each of the first guide vanes taper due to a varying shape of front edge of the first guide vane and each of the second guide vanes taper due to a further varying shape of the second guide vane.",
    "8. The continuous-flow machine as recited in claim 1, wherein each of the first guide vanes tapers due to a varying shape of rear edge of the first guide vanes and each of the second guide vanes tapers due to a further varying shape of front edge of the second guide vane of appertaining second guide vane.",
    "9. The continuous-flow machine as recited in claim 1, wherein each of the first guide vanes tapers due to a varying shape of both a first guide vane rear edge and front edge and each of the second guide vanes tapers due to a varying shape of both a second guide vane rear edge and front edge.",
    "10. The continuous-flow machine as recited in claim 1 wherein an edge of one of the first and second guide vanes is both convex and concave with respect to the vane body.",
    "11. The continuous-flow machine as recited in claim 1, wherein an edge of one of the first and the second guide vanes has a stepped contour having at least two stepped transitions.",
    "12. The continuous-flow machine as recited in claim 1, wherein the taper of each of the first guide vanes amounts to 30% to 70% of the maximum width of each second guide vane, or the taper of each of the second guide vanes amounts to 30% to 70% of the maximum width of each of the first guide vanes.",
    "13. The continuous-flow machine as recited in claim 1 wherein the first guide vanes and the second guide vanes that are each in the same position along the longitudinal axis have different curvatures of their blade skeleton lines or different profile mean lines.",
    "14. The continuous flow machine according to claim 1, wherein in the radial direction each of the first and the second guide vanes has an inner tapering deflecting a flow outwardly, and an outer tapering deflecting a flow inwardly to provide stability of a flow in the continuous-flow machine.",
    "15. The continuous-flow machine as recited in claim 1, wherein one of the first guide vanes and one of the second guide vanes form a unit, and a plurality of the units are evenly distributed in the circumferential direction whereby distances between adjacent one of said first and one of said second guide vanes are equal to each other.",
    "16. The continuous-flow machine as recited in claim 2 wherein three of the guide vanes form the unit.",
    "17. The continuous-flow machine as recited in claim 5 wherein the overlapping area is located in an area of 30% to 70% of a channel height defined by a length of the vane body along the longitudinal axis.",
    "18. The continuous-flow machine as recited in claim 13 wherein the first guide vanes and the second guide vanes each have the different curvatures of the skeleton lines or the different profile mean lines in an outer area and in an inner area in the radial direction.",
    "19. An axial compressor comprising a continuous-flow machine, the continuous flow machine further including: at least one guide vane ring, the guide vane ring defining radial, circumferential and axial directions, the guide vane ring including at least one row of a plurality of guide vanes spaced in the circumferential direction, each guide vane of the plurality of guide vanes having a vane body with a longitudinal axis in the radial direction between a base and a tip, the plurality of guide vanes including first guide vanes and second guide vanes, each first guide vane being tapered along the longitudinal axis so that the vane body becomes narrower at the tip than the base and each second guide vane being tapered in an opposite direction along the longitudinal axis so that the vane body becomes wider at the tip than the base."
  ],
  "description_excerpt": "This claims the benefit of European Patent Application EP 121 797 79.9, filed Aug. 9, 2012, and hereby incorporated by references herein.\n\nThe invention relates to a continuous-flow machine, especially an axial compressor, with at least one guide vane ring, and it also relates to a method for increasing the stability of the flow in a continuous-flow machine.\n\nContinuous-flow machines often have adjustable guide vanes, especially in the front stages of compressors. Depending on the operating state of the continuous-flow machine, they are used to adjust the inflow angles to the runner blades downstream and to regulate the energy conversion of the stage consisting of the guide vanes and the runner blades. When the guide vanes are adjusted, the flow angle changes over the entire height of the channel. When the operating state changes, however, the distribution of the local mass flow along the height of the channel changes. This can diminish the stability of the flow in the continuous-flow machine and reduce the efficiency.\n\nVarious measures are known for increasing the stability of the flow in a continuous-flow machine. For example, European patent application EP 0 745 755 A1 describes a specially shaped guide vane for a compressor of a gas turbine. The guide vane has a rear edge that is angled towards the blade root. The use of such guide vanes improves the stability of the flow and thus increases the compressor pump limit. A drawback here is that the geometry of the guide vanes is adapted to a specific operating state and, if a deviation from the operating state occurs, an improved flow is no longer ensured.",
  "cpc": [
    "F01D 9/041",
    "F01D 17/162",
    "F01D 5/141",
    "F01D 5/146",
    "F01D 9/04",
    "F04D 29/544",
    "F04D 29/563",
    "F05D 2240/121",
    "F05D 2240/122",
    "F05D 2270/10",
    "F05D 2270/102"
  ],
  "ipc": [
    "F01D 9/04",
    "F01D 17/16",
    "F01D 5/14",
    "F04D 29/54",
    "F04D 29/56"
  ],
  "assignees": [
    "MTU Aero Engines AG"
  ],
  "inventors": [
    "Roland Wunderer"
  ],
  "filing_date": "2013-08-07",
  "publication_date": "2016-11-29",
  "grant_date": "2016-11-29",
  "priority_date": "2012-08-09",
  "family_id": "46642433",
  "cited_by_count": 2,
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}