A shrouded fluid turbine comprises an impeller and a turbine shroud surrounding the impeller. The inlet of the turbine shroud is flared. The shroud includes alternating inward and outward curving lobe segments along a trailing edge of the turbine shroud. The inward and outward curving lobe segments have exposed lateral surfaces, or in other words do not have sidewalls joining the inward and outward curving lobe segments. This allows for both transverse mixing and radial mixing of air flow through the turbine shroud with air flow passing along the exterior of the turbine shroud.
1. A fluid turbine, comprising:
a turbine shroud comprising:
a first structural member defining a flared inlet of the turbine shroud; and
a plurality of lobe segments defining a trailing edge of the turbine shroud, the plurality of lobe segments including inward curving lobe segments and outward curving lobe segments configured in an alternating pattern to allow fluid to mix laterally and transversely, wherein each of the lobe segments includes a front end and a mixing end, and the front ends of the plurality of lobe segments form the first structural member; and
an ejector shroud disposed downstream of and concentrically about the turbine shroud.
2. The fluid turbine of claim 1 , wherein each inward curving lobe segment has two exposed lateral surfaces, and wherein each outward curving lobe segment has two exposed lateral surfaces.
3. The fluid turbine of claim 1 , wherein the plurality of lobe segments has a total of nine inward curving lobe segments and nine outward curving lobe segments.
4. The fluid turbine of claim 1 , wherein the outward curving lobe segments are wider in the circumferential direction than the inward curving lobe segments.
5. The fluid turbine of claim 1 , wherein the front end of each lobe segment includes a groove on an interior surface.
6. The fluid turbine of claim 1 , wherein the inward curving lobe segments and outward curving lobe segments are comprised of a composite material or a fabric material.
7. The fluid turbine of claim 6 , wherein the composite material is a mixture of fiberglass and a polymer resin.
8. The fluid turbine of claim 6 , wherein the fabric material is fiberglass coated with a fluoropolymer.
9. A fluid turbine, comprising:
a turbine shroud, the turbine shroud comprising:
a plurality of inward curving lobe segments, each inward curving lobe segment having a front end, a mixing end, and two lateral surfaces; and
a plurality of outward curving lobe segments, each outward curving lobe segment having a front end, a mixing end, and two lateral surfaces; and
an ejector shroud downstream of the turbine shroud;
wherein each inward curving lobe segment is located between two outward curving lobe segments, and each outward curving lobe segment is located between two inward curving lobe segments;
wherein the front ends of the inward curving lobe segments and the front ends of the outward curving lobe segments form a first structural member defining a flared inlet of the shroud;
wherein the mixing ends of the inward curving lobe segments and the mixing ends of the outward curving lobe segments form a plurality of lobe segments that define a trailing edge of the shroud; and
wherein the two lateral surfaces of the inward curving lobe segments and the two lateral surfaces of the outward curving lobe segments are exposed along the trailing edge.
10. A shrouded fluid turbine comprising:
an impeller;
a turbine shroud surrounding the impeller, the turbine shroud including:
a first structural member defining a flared inlet of the shroud; and
a plurality of lobe segments defining a trailing edge of the turbine shroud, the plurality of lobe segments including inward curving lobe segments and outward curving lobe segments configured in an alternating pattern, wherein two lateral surfaces of the inward curving lobe segments and two lateral surfaces of the outward curving lobe segments are exposed along the trailing edge;
an ejector shroud, the trailing edge of the turbine shroud extending into an inlet end of the ejector shroud; and
a plurality of support members extending between the turbine shroud and the ejector shroud, each support member being aligned with an outward curving lobe segment.
11. The fluid turbine of claim 10 , wherein the ejector shroud comprises a plurality of ejector lobe segments.
12. The fluid turbine of claim 10 , wherein the ejector shroud has the shape of a ring airfoil.
13. The fluid turbine of claim 10 , wherein the plurality of lobe segments has a total of nine inward curving lobe segments and nine outward curving lobe segments.
14. The fluid turbine of claim 10 , wherein the outward curving lobe segments are wider in the circumferential direction than the inward curving lobe segments.
15. The fluid turbine of claim 10 , wherein each lobe segment comprises a front end and a mixing end, and the front ends of the plurality of lobe segments form the first structural member.
16. The fluid turbine of claim 15 , wherein the front end of each lobe segment includes a groove on an interior surface.
17. The fluid turbine of claim 10 , wherein the impeller comprises a nacelle body and a plurality of stator vanes extending between the nacelle body and the turbine shroud.
18. The fluid turbine of claim 17 , wherein the nacelle body comprises a central passageway.