Patent Application
20180320930
Solar thermal power plants, also called concentrating solar power plants, concentrate sunlight to heat a fluid and transport the thermal energy of the heated fluid to drive a process such as electricity-generating turbines or engines. The fluid flows through concentrating solar collector assemblies, which include parabolic troughs and receiver tube(s). The parabolic troughs include a reflective surface that reflects the incident sunlight onto the receiver, through which the fluid flows. The parabolic trough, together with the receiver, may be rotated to track the sun. A space frame provides structural support for the parabolic trough. The space frame experiences significant torsional loads caused, for example, by wind. The space frame must hold the weight of the parabolic trough, particularly as it is rotated, and not fail under the torsional loads. The space frame must further provide sufficient stiffness, such that the parabolic troughs do not deflect from the desired position for optimal collection of light. With all these requirements, the space frame may account for approximately 25% of the total installation cost of a concentrating solar collector assembly.
Applicant has developed octahedral space frames that are capable of efficiently carrying torsional loads while maintaining torsional stiffness. In certain embodiments, the octahedral space frames support a parabolic trough of a concentrating solar collector assembly. In particular embodiments, the octahedral space frames include a plurality of double octahedral structures, disposed in a row, each double octahedral structure including two single octahedron structures. Certain embodiments of the featured octahedral space frames include a V-shaped opening formed when viewing the octahedral space frame in a longitudinal direction. Certain embodiments include a parabolic trough supported in the V-shaped opening of the octahedral space frame.
In an aspect, an octahedral space frame includes a first plurality of double octahedral structures disposed in a first row in a longitudinal direction, adjacent ones of the first plurality of double octahedral structures sharing two common members. In an embodiment of this aspect, each of the first plurality of double octahedral structures includes respective first and second single octahedron structures joined in a transverse direction and sharing three common members, the transverse direction being orthogonal to the longitudinal direction.
In an embodiment, for example, the first plurality of double octahedral structures collectively forms a V-shaped opening, as seen when the octahedral space frame is viewed in the longitudinal direction.
In an embodiment, for example, the V-shaped opening has an internal angle greater than 0 degrees and less than or equal to 180 degrees.
In an embodiment, for example, each of the first plurality of double octahedral structures includes twenty one members.
In an embodiment, for example, each of the twenty one members of each of the first plurality of double octahedral structures has equal length.
In an embodiment, for example, the octahedral space frame has a rectangular outline as seen when viewed in the longitudinal direction.
In an embodiment, for example, each of the first plurality of double octahedral structures includes twenty one members, wherein seven members of the twenty one members have a common first length and fourteen members of the twenty one members have a common second length, the second length being different from the first length.
In an embodiment, for example, the octahedral space frame further includes: a first axial chord joining each first single octahedron structure of the first plurality of double octahedral structures in the longitudinal direction; and a second axial chord joining each second single octahedron structure of the first plurality of double octahedral structures in the longitudinal direction.
In an embodiment, for example, the octahedral space frame further includes: a first plurality of axial chords joining each first single octahedron structure of the first plurality of double octahedral structures in the longitudinal direction; and a second plurality of axial chords joining each second single octahedron structure of the first plurality of double octahedral structures in the longitudinal direction.
In an embodiment, for example, the octahedral space frame further includes an end member assembly disposed at an end of the first plurality of double octahedral structures. In this embodiment, the end member assembly includes: one or more first end members connected to the first single octahedral structure of an end one of the first plurality of double octahedral structures; and one or more second end members connected to the second single octahedral structure of the end one of the first plurality of double octahedral structures.
In an embodiment, for example, the octahedral space frame further includes a torque transfer assembly disposed at the end one of the first plurality of double octahedral structures.
In an embodiment, for example, the torque transfer assembly includes at least one torque transfer plate and a central torsion element.
In an embodiment, for example, the octahedral space frame further includes a second plurality of double octahedral structures disposed in a second row in the longitudinal direction, adjacent ones, in the longitudinal direction, of the second plurality of double octahedral structures sharing two common members, the first and second rows being joined in the transverse direction.
In an embodiment, for example, each of the second plurality of double octahedral structures includes twenty one members.
In an embodiment, for example, the first and second rows share at least one common axial chord.
In an embodiment, for example, the octahedral space frame further includes a third plurality of double octahedral structures disposed in a third row in the longitudinal direction, adjacent ones, in the longitudinal direction, of the third plurality of double of octahedral structures sharing two common members, the third row being joined to each of the first and second rows in a vertical direction orthogonal to each of the longitudinal and transverse directions.
In another aspect, a concentrating solar collector assembly includes an octahedral space frame. In an embodiment of this aspect, the octahedral space frame includes a plurality of double octahedral structures disposed in a first row in a longitudinal direction, adjacent ones of the plurality of double octahedral structures sharing two common members, the plurality of double octahedral structures collectively forming a V-shaped opening in the octahedral space frame, as seen when the octahedral space frame is viewed in the longitudinal direction. In an embodiment of this aspect, each of the plurality of double octahedral structures includes respective first and second single octahedron structures joined in a transverse direction and sharing three common members, the transverse direction being orthogonal to the longitudinal direction. In an embodiment of this aspect, the octahedral space frame further includes a parabolic trough disposed in the V-shaped opening in the octahedral space frame.
In an embodiment, for example, the V-shaped opening has an internal angle greater than 0 degrees and less than or equal to 180 degrees.
In an embodiment, for example, the concentrating solar collector assembly further includes a receiver configured to carry a heat transfer fluid, the parabolic trough being configured to reflect light incident on the parabolic trough onto the receiver.
In an embodiment, for example, the concentrating solar collector assembly further includes receiver support elements configured to structurally support the receiver.
In an embodiment, for example, the receiver has an elongated axis extending in the longitudinal direction.
In an embodiment, for example, the concentrating solar collector assembly further includes a fluid distribution subsystem configured to circulate the heat transfer fluid through the receiver.
In an embodiment, for example, each of the plurality of double octahedral structures of the octahedral space frame includes twenty one members.
In an embodiment, for example, each of the twenty one members of each of the plurality of double octahedral structures has an equivalent length.
In an embodiment, for example, the octahedral space frame, of the concentrating solar collector assembly, further includes: a first axial chord joining each first single octahedron structure of the plurality of double octahedral structures in the longitudinal direction; and a second axial chord joining each second single octahedron structure of the plurality of double octahedral structures in the longitudinal direction.
In an embodiment, for example, the octahedral space frame, of the concentrating solar collector assembly, further includes: a first plurality of axial chords joining each first single octahedron structure of the first plurality of double octahedral structures in the longitudinal direction; and a second plurality of axial chords joining each second single octahedron structure of the first plurality of double octahedral structures in the longitudinal direction.
In an embodiment, for example, the octahedral space frame, of the concentrating solar collector assembly, further includes an end member assembly disposed at an end of the plurality of double octahedral structures. In this embodiment, the end member assembly includes: one or more first end members connected to the first single octahedral structure of an end one of the plurality of double octahedral structures; and one or more second end members connected to the second single octahedral structure of the end one of the plurality of double octahedral structures.
In an embodiment, for example, the octahedral space frame, of the concentrating solar collector assembly, further includes a torque transfer assembly disposed at the end one of the plurality of double octahedral structures.
In an embodiment, for example, the torque transfer assembly, of the concentrating solar collector assembly, further includes at least one torque transfer plate and a central torsion element.
In an embodiment, for example, the concentrating solar collector assembly further includes: a plurality of pylons configured to support the octahedral space frame and the parabolic trough; and a tracking subsystem configured to rotate the octahedral space frame and the parabolic trough with respect to the plurality of pylons, to track an incident light source.
In another aspect, a method for supporting a parabolic trough in a concentrating solar collector assembly includes: transferring weight of the parabolic trough to an octahedral space frame including a plurality of double octahedral structures disposed in a first row in a longitudinal direction, wherein (a) adjacent ones of the plurality of double octahedral structures share two common members and (b) each of the plurality of double octahedral structures includes respective first and second single octahedron structures joined in a transverse direction and sharing three common members, the transverse direction being orthogonal to the longitudinal direction; and transferring weight of the parabolic trough and the octahedral space frame to a base surface via a plurality of pylons.
In an embodiment, for example, the method for supporting a parabolic trough further includes carrying torsional load while maintaining torsional stiffness.
In an embodiment, for example, the base surface is a ground surface.
In an embodiment, a method for capturing solar energy includes: the method for supporting a parabolic trough in a concentrating solar collector assembly; reflecting light incident on the parabolic trough onto a receiver; and circulating a heat transfer fluid through the receiver.
In an embodiment, for example, the method for capturing solar energy further includes rotating the parabolic trough and the octahedral space frame with respect to the plurality of pylons to track an incident light source.
In general the terms and phrases used herein have their art-recognized meaning, which can be found by reference to standard texts, journal references and contexts known to those skilled in the art.
Referring to the drawings, like numerals indicate like elements and the same number appearing in more than one drawing refers to the same element.
Without wishing to be bound by any particular theory, there may be discussion herein of beliefs or understandings of underlying principles relating to the devices and methods disclosed herein. It is recognized that regardless of the ultimate correctness of any mechanistic explanation or hypothesis, an embodiment of the invention can nonetheless be operative and useful.
Applicant discloses space frames and associated systems and methods where face- and/or edge-sharing octahedral structures are configured to produce a multi-layer grid space frame. Certain embodiments of the space frames form a planar surface, complex surface, or a combination of planer and complex surfaces. The space frames are used, for example, as a support structure for a parabolic trough used in a concentrated solar power application. Each space frame, henceforward referred to as an octahedral space frame, includes multiple pairs of face sharing double octahedral structures repeated along an axis and sharing edges to produce a long structure for supporting a parabolic trough, in certain embodiments.
Certain embodiments of the octahedral space frames provide structural support when used with parabolic troughs, as part of a concentrating solar collector assembly. The octahedral space frames efficiently carry a torsional load, while maintaining torsional stiffness, with low overall weight.
A further advantage of certain embodiments of the octahedral space frames is reduced complexity. In certain embodiments, members (e.g., struts and/or chords) are of the same length, thereby allowing the majority of struts used in the manufacture of an octahedral space frame to be of the same length. In this embodiment, the octahedral space frame takes a form desirable for a parabolic trough application in which the parabolic trough is cradled in the V-shape defined by the structure. As a result, additional space frame elements may be unnecessary or minimal to support the parabolic trough. The octahedral space frames featured herein provide reduced installation cost compared to conventional space frames.
Certain configurations of the octahedral space frames could also have utility in the architectural, civil, structural and other engineering fields where a configurable, multi-layer grid space frame structure is desirable.
An octahedral space frame includes one or more double octahedral structures, each of which includes two single octahedron structures.
Octahedral space frame 400 further includes an end member assembly 440 proximate each of first and second longitudinal ends 410 and 412. In this embodiment, each end member assembly 440 includes end axial chords 406 and end members 442. Each end axial chord 406 is connected to nearest upper vertex 252 proximate the respective longitudinal end, 410 or 412, and respective transverse side, 414 or 416, to proximate end members 442 at respective longitudinal end and respective transverse side of octahedral space frame 400, as illustrated in
In certain embodiments, the octahedral spaces frame featured herein may have any combination of features of octahedral space frame 400 and octahedral space frame 500.
Certain embodiments of the octahedral space frame featured herein include more than one plurality of double octahedral structures 300, effectively joined in transverse direction 206, and one or more double octahedral structures 250 included in each plurality of double octahedral structures 300. For example,
Certain embodiments of the octahedral space frame featured herein include single octahedron structures 200 that are irregular octahedrons in their shape, such as those illustrated in
In other embodiments, an octahedral space frame includes double octahedral structures effectively joined in a vertical direction 1302, which is orthogonal to longitudinal and transverse directions 208 and 206.
Having now fully described the present invention in some detail by way of illustration and examples for purposes of clarity of understanding, it will be clear to one of ordinary skill in the art that the same can be performed by modifying or changing the invention within a wide and equivalent range of conditions, formulations and other parameters without affecting the scope of the invention or any specific embodiment thereof, and that such modifications or changes are intended to be encompassed within the scope of the appended claims.
The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments, exemplary embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention as defined by the appended claims. The specific embodiments provided herein are examples of useful embodiments of the present invention and it will be apparent to one skilled in the art that the present invention may be carried out using a large number of variations of the devices, device components, methods steps set forth in the present description. Methods and devices useful for the present methods can include a large number of optional composition and processing elements and steps.
When a group of substituents is disclosed herein, it is understood that all individual members of that group and all subgroups are disclosed separately. When a Markush group or other grouping is used herein, all individual members of the group and all combinations and subcombinations possible of the group are intended to be individually included in the disclosure.
It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural reference unless the context clearly dictates otherwise. Thus, for example, reference to “a heating pipe” includes a plurality of such heating pipes and equivalents thereof known to those skilled in the art, and so forth. As well, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably. The expression “of any of claims XX-YY” (wherein XX and YY refer to claim numbers) is intended to provide a multiple dependent claim in the alternative form, and in some embodiments is interchangeable with the expression “as in any one of claims XX-YY.”
Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.
Whenever a range is given in the specification, for example, a temperature range, a time range, or a composition or concentration range, all intermediate ranges and subranges, as well as all individual values included in the ranges given are intended to be included in the disclosure. As used herein, ranges specifically include the values provided as endpoint values of the range. For example, a range of 1 to 100 specifically includes the end point values of 1 and 100. It will be understood that any subranges or individual values in a range or subrange that are included in the description herein can be excluded from the claims herein.
As used herein, “comprising” is synonymous with “including,” “containing,” or “characterized by,” and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. As used herein, “consisting of” excludes any element, step, or ingredient not specified in the claim element. As used herein, “consisting essentially of” does not exclude materials or steps that do not materially affect the basic and novel characteristics of the claim. In each instance herein any of the terms. “comprising”, “consisting essentially of” and “consisting of” may be replaced with either of the other two terms.
Herein, and unless otherwise indicated, the term “exemplary” means serving as an example, instance, or illustration.
One of ordinary skill in the art will appreciate that device elements and combinations of components other than those specifically exemplified can be employed in the practice of the invention without resort to undue experimentation. All art-known functional equivalents, of any such materials and methods are intended to be included in this invention. The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention that in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention as defined by the appended claims.
