U.S. patent application number 11/735835 was filed with the patent office on 2008-10-16 for regenerator wheel apparatus.
This patent application is currently assigned to WILSON TURBOPOWER, INC.. Invention is credited to Jon M. Ballou, Kelly Ward, David Gordon Wilson.
Application Number | 20080251234 11/735835 |
Document ID | / |
Family ID | 39852659 |
Filed Date | 2008-10-16 |
United States Patent
Application |
20080251234 |
Kind Code |
A1 |
Wilson; David Gordon ; et
al. |
October 16, 2008 |
REGENERATOR WHEEL APPARATUS
Abstract
A regenerator wheel is disclosed. The regenerator wheel includes
a framework, a plurality of ports disposed within the framework,
with at least one port of the plurality of ports separated from
another port by the framework. The regenerator wheel also includes
a plurality of matrixes aligned individually with the plurality of
ports.
Inventors: |
Wilson; David Gordon;
(Winchester, MA) ; Ballou; Jon M.; (Beverly,
MA) ; Ward; Kelly; (Peabody, MA) |
Correspondence
Address: |
CANTOR COLBURN, LLP
20 Church Street, 22nd Floor
Hartford
CT
06103
US
|
Assignee: |
WILSON TURBOPOWER, INC.
WOBURN
MA
|
Family ID: |
39852659 |
Appl. No.: |
11/735835 |
Filed: |
April 16, 2007 |
Current U.S.
Class: |
165/8 |
Current CPC
Class: |
F28D 19/041 20130101;
Y02E 20/34 20130101; Y02E 20/348 20130101; F23L 15/02 20130101 |
Class at
Publication: |
165/8 |
International
Class: |
F23L 15/02 20060101
F23L015/02 |
Claims
1. A regenerator wheel comprising: a framework, a plurality of
ports disposed within the framework, at least one port of the
plurality of ports separated from another port by the framework;
and a plurality of matrixes aligned individually with the plurality
of ports.
2. The wheel as claimed in claim 1, wherein: at least one matrix of
the plurality of matrixes comprises at least one straight flow
passage.
3. The wheel as claimed in claim 2, wherein: at least one matrix
comprises a honeycomb configuration.
4. The wheel as claimed in claim 1, wherein: at least one matrix of
the plurality of matrixes is embedded within the framework.
5. The wheel as claimed in claim 4, wherein: the framework and the
at least one matrix are the same material.
6. The wheel as claimed in claim 5, wherein: the framework and the
at least one matrix are ceramic.
7. The wheel as claimed in claim 1, wherein: at least one matrix of
the plurality of matrixes comprises extruded ceramic honeycomb.
8. The wheel as claimed in claim 1, wherein: the framework
comprises a single piece structure.
9. The wheel as claimed in claim 8 wherein the single piece
structure is a foamed structure.
10. The wheel as claimed in claim 1, wherein: the framework
comprises a set of side plates, each side plate comprising the
plurality of ports; and at least one matrix of the plurality of
matrixes is disposed within a corresponding set of the plurality of
ports.
11. The wheel as claimed in claim 10, wherein the framework further
comprises: at least one spacer disposed between two side plates of
the set of side plates.
12. The wheel as claimed in claim 10, further comprising: a ceramic
binder between at least one matrix and the corresponding set of the
plurality of ports.
13. The wheel as claimed in claim 12, wherein: at least one of the
set of side plates and the ceramic binder comprise the same
material as the at least one matrix.
14. The wheel as claimed in claim 10, wherein: at least one of the
framework and the at least one matrix comprise a set of axial
retention features.
15. The wheel as claimed in claim 14, wherein: the at least one
matrix is a floating matrix within the set of axial retention
features.
16. The wheel as claimed in claim 1, further comprising: a flexible
binder disposed between each port of the plurality of ports and
each corresponding matrix of the plurality of matrixes.
17. The wheel as claimed in claim 1, wherein the framework
comprises: a set of side plates, each side plate having at least
one straight flow passage corresponding to each port of the
plurality of ports; a boundary plate disposed between outer edges
of the set of side plates, thereby defining a space between the set
of side plates and an outer boundary of the wheel; and at least one
separator plate disposed within the space between the set of side
plates, thereby defining the plurality of ports.
18. The wheel as claimed in claim 17, wherein: the plurality of
matrixes comprise a cloth-like material.
19. The wheel as claimed in claim 17, wherein: the at least one
separator plate is a unitized structure.
20. The wheel as claimed in claim 17, wherein: one side plate of
the set of side plates, the boundary plate, and the at least one
separator plates are a unitized structure.
21. The wheel as claimed in claim 1 wherein the framework
comprises: a boundary plate defining an outer boundary of the
wheel, the boundary plate defining an open space; and at least one
separator plate disposed within the open space of the boundary
plate, thereby defining a plurality of open ports.
22. The wheel as claimed in claim 21 wherein: the matrix comprises
a rigid filler material.
23. The wheel as claimed in claim 21 wherein: the matrix comprises
a rigidized ceramic cloth material disposed within the plurality of
open ports.
24. A regenerator wheel comprising: a plurality of distinct
matrixes, each matrix comprising at least one flow passage; and
means for supporting the plurality of distinct matrixes.
25. The wheel as claimed in claim 24, further comprising: a
flexible binder disposed between the plurality of distinct matrixes
and the means for supporting.
26. The wheel as claimed in claim 24, wherein: the plurality of
distinct matrixes and the means for supporting comprise the same
material.
27. The wheel as claimed in claim 26, wherein: the means for
supporting comprises a framework of filler material.
28. The wheel as claimed in claim 24, wherein: the means for
supporting comprises a set of side plates.
Description
BACKGROUND OF THE INVENTION
[0001] This disclosure relates generally to regenerative heat
exchangers, and more particularly to a regenerator wheel
apparatus.
[0002] Regenerative heat exchangers, or regenerators, also known as
heat wheels, are used for energy recovery associated with
operations involving heating and cooling. One example of heating
and cooling for which such regenerators are employed is that of
large spaces such as buildings. Regenerators are used in preheating
operations in, for example, steam power plants and in gas
adsorption processes and mass transfer operations, such as
dehumidification, for example. In order to achieve the results
desired, regenerators include what has become known as a matrix.
The matrix is the portion of the regenerator that does the
absorption and transfer of a specific target species, such as heat,
etc. Since operating temperatures of regenerators utilized as noted
can exceed 650 degrees Celsius, matrixes are often constructed of
ceramic materials. Moreover, ceramics generally have a lower
thermal conductivity than metals, which is favorable in
regenerative heat exchange applications.
[0003] Regenerators have traditionally been configured in several
ways to transport the matrix between flow streams of high and low
species concentration, such as continuous and discontinuous
rotation of the matrix in a regenerator wheel, for example. Often,
a significant portion of the mass and/or area of the regenerator
wheel comprises the matrix. While some regenerators configured with
discontinuous rotation of the regenerator wheel, such as described
in U.S. RE37,134, the contents of which are herein incorporated by
reference in their entirety, use all of the mass and/or area of the
matrix to absorb and transfer the specific target species, others
do not. One example of a regenerator that does not use all of the
mass and/or area of the matrix is one that is indexed to a finite
number of species flow streams, such as four for example. In such
devices, a significant area of the matrix may not be used for the
purpose for which it is configured.
[0004] Because of the cost associated with the production of
matrixes, non-utilized sections are not desirable. Furthermore,
unused sections of matrix material are undesirable because the
matrix itself, especially when made of ceramic material, tends to
be on the less robust side with respect to structural durability.
Other materials which offer effective heat transfer properties for
regenerators do not have the needed structural integrity to be used
exclusively as the matrix material.
BRIEF DESCRIPTION OF THE INVENTION
[0005] An embodiment of the invention includes a regenerator wheel.
The regenerator wheel includes a framework, a plurality of ports
disposed within the framework, with at least one port of the
plurality of ports separated from another port by the framework.
The regenerator wheel also includes a plurality of matrixes aligned
individually with the plurality of ports.
[0006] Another embodiment of the invention includes a regenerator
wheel having a plurality of distinct matrixes, each matrix
comprising at least one flow passage, and means for supporting the
plurality of distinct matrixes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The following descriptions should not be considered limiting
in any way. With reference to the accompanying drawings, like
elements are numbered alike:
[0008] FIG. 1 is an end view of a regenerator wheel in accordance
with an embodiment of the invention,
[0009] FIG. 2 is a section view of a regenerator wheel in
accordance with an embodiment of the invention;
[0010] FIG. 3 is a section view of a regenerator wheel in
accordance with an embodiment of the invention;
[0011] FIG. 4 is a an end section view of a regenerator wheel
framework in accordance with an embodiment of the invention;
[0012] FIG. 5 is a section view of the regenerator wheel framework
shown in FIG. 4 in accordance with an embodiment of the
invention;
[0013] FIG. 6 is a section view of a regenerator wheel framework in
accordance with an embodiment of the invention; and
[0014] FIG. 7 is an end view of a regenerator wheel framework in
accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] A detailed description of several embodiments of the
disclosed apparatus and method are presented herein by way of
exemplification and not limitation with reference to the
figures.
[0016] An embodiment of the invention provides a discontinuously
rotated or indexed regenerator wheel wherein matrix material is
disposed only where useful to transfer the target species, such as
at a plurality of ports in a framework. The ports are then
alignable with a flow stream of the target species. The ports are
appropriately distributed within the regenerator wheel (in one
embodiment equally spaced) and their form is based on the shape of
the ducts that lead the stream of the target species to and from
the matrix. The framework provides enhanced structural integrity
and rigidity for the often brittle matrix material. Furthermore,
manufacturing costs associated with the matrix representing a
significant portion of the mass and/or area of the regenerator
wheel can be avoided while maintaining performance of the
regenerator. As used herein, the term "regenerator" shall include
regenerators used in energy recovery, preheating, exhaust
treatment, gas adsorption, and mass transfer applications among
others.
[0017] Referring now to FIG. 1, a regenerator wheel 50 for use with
a discontinuously rotating (or indexing) regenerator is depicted.
Evident is that the area of the wheel 50 is made up of both areas
not intended for species transfer and ports (where the active
matrix resides) that are intended to have utility with respect to
species transfer.
[0018] The regenerator wheel 50 comprises a framework 55. Framework
55 may be constructed in a number of different ways providing it
affords a reliable structure to support and move the matrixes
correctly to promote proper operation of the regenerator. Five
embodiments are illustrated herein for exemplary purposes but are
not to be considered limiting. The first embodiment disclosed is
illustrated in FIG. 1 while the second embodiment is illustrated in
FIGS. 2 and 3, the third embodiment is illustrated in FIGS. 4 and
5, with the fourth embodiment depicted in FIG. 6 and the fifth
embodiment depicted in FIG. 7 In each embodiment, the framework 55
is illustrated as a cylindrical body. Though a cylinder is a
convenient shape to work with for a rotary machine, it will be
understood that other shapes are also possible without departing
from the scope of the invention.
[0019] The framework is either of relatively solid construction or
constructed of individual components and therefore mostly open. It
is to be appreciated that the relatively solid configuration
includes foamed material construction (e.g. ceramic foams as
marketed by Vesuvius, Belgium). First and second end faces 20 and
22 (best seen with reference to FIG. 2) are presented. These are
the faces that interact with fluid flow conduits (not shown) during
use of the regenerator. Whereas the use of the face area is a
convenient arrangement for a rotary regenerator, departing from
this scheme and using, for example, the outer and inner surfaces of
a tube shaped regenerator wheel are still within the scope of the
present invention. At each end face 20, 22 is located a plurality
of ports 65 (illustrated as four in FIG. 1). Within each port 65 is
securely disposed one of a plurality of matrixes 60, which may in
one embodiment comprise ceramic honeycomb structures, each having
at least one passage through which fluid flow (and target species
transfer) occurs.
[0020] Each of the plurality of matrixes 60 is sized for a specific
application. In some embodiments of the invention, all of the
matrixes 60 in a particular wheel 50 will be of the same outer
dimension while in other embodiments, differing dimensions are
utilized. In general, there will be at least two matrixes 60 of
equivalent size in each size category of a wheel 50 since species
transfer requires movement of a matrix from one stream to another
(usually swapping one matrix for another). Furthermore, sealing
with the two streams is more easily facilitated by matrixes that
have a same outside dimension. Ports 65 may be located relative to
each other on each end face 20 or 22 in any pattern needed to match
the locations of the fluid flow feeds (not shown) and the index of
the regenerator wheel 50. In a radial flow regenerator, as
mentioned above, the port sections may be located on the inner and
outer faces of the tube shaped regenerator wheel.
[0021] In one embodiment, the at least one passage in each of the
plurality of matrixes 60 is disposed perpendicularly to end faces
20 and 22, although it is possible to dispose such passages
angularly with respect to the faces 20, 22 if a particular
application calls for such an angle. Moreover, while four ports 65
are illustrated, more or fewer are contemplated.
[0022] With respect to matrix material, it is to be appreciated
that any type of matrix material may be incorporated in the
configurations disclosed herein.
[0023] Returning now to the structure of framework 55, it should be
noted that it is desirable that the framework 55 be of light weight
to reduce inertia thereof, thereby reducing the amount of force
required to index the regenerator wheel 50 from one index position
to another. This results in a savings of material and construction
costs with respect to the robustness of the machine tasked with
rotating the wheel 50 and additionally promotes speedier indexing
movements. Speedier indexing movements result in smaller losses due
to leakage or decay of the absorbed species. Simultaneously, the
framework 55 provides appropriate rigidity to ensure accurate
registration of the plurality of matrixes 60 disposed within the
plurality of ports 65 with the fluid flow feeds (not shown) through
repeated movements of the regenerator wheel 50.
[0024] Because the framework 55 is required to provide structural
support to the plurality of matrixes 60 and does not need to absorb
or transport the target species, it can be made from a variety of
materials and processes which, relative to matrix 61 materials and
manufacturing processes represent, among other advantages, reduced
costs. Furthermore, because the framework 55 does not need to
absorb or transport the target species, it may, as noted above, be
solid, or have any appropriate structural arrangement to provide
enhanced structural integrity, support, and durability as compared
to a regenerator wheel that includes a large area of unused matrix
61 material.
[0025] As depicted in FIG. 1, one embodiment of the framework 55 is
a single piece structural support, made of a filler material 62
with the plurality of ports 65 machined, milled, drilled, or
otherwise formed therein. Matrix 60 material is then attached
therein adhesively, by interference fit, or otherwise. In one
embodiment, the filler material 62 of the framework 55 is the same
material as the plurality of matrixes 60 (except that a structure
of the framework 55 does not necessarily include the flow passages
of the matrix 60 material). Accordingly, the plurality of matrixes
60 and the framework 55 of the regenerator wheel 50 have similar
thermal response properties, such as a coefficient of thermal
expansion, for example. The framework 55, having similar thermal
response properties facilitates maintenance of a substantially
uniform thermal expansion throughout the regenerator wheel 50 to
reduce thermal stress and enhance structural integrity, thereby
reducing possible seal leakage, which may be influenced by warpage
of the regenerator wheel 50. As used herein, the term
"substantially uniform thermal expansion" in one embodiment shall
refer to a thermal expansion ratio of the matrix 60 to the
framework 55 contemplated to be no greater than about 1.001 and no
less than about 0.999. Such uniform thermal expansion enhances the
structural integrity of the entire wheel 50 to reduce seal leakage
that may result from deflection of the sealing surface, such as the
first and second end faces 20, 22 for example. Tuning of the
thermal expansion is significant in the case when the matrixes 60
are bonded into the framework 55, as will be described further
below, and preferable if the framework 55 is made of side plates,
as will also be described further below. The substantially uniform
thermal expansion throughout the regenerator wheel 50 also reduces
an accumulation of thermal stresses in response to at least one of
an application of high temperatures to the regenerator wheel 50 and
a difference in temperatures between a high temperature flow stream
and a low temperature flow stream.
[0026] In order to reduce a significance of the substantially
uniform thermal expansion coefficient while maintaining functional
suitability of the wheel 50, a layer of flexible binder 69 is
disposed between each port 65 of the framework 55 and each matrix
60 to compensate for a thermal expansion differential therebetween.
It will be appreciated that material of the layer shall withstand
the operating temperatures and be flexible in nature. One example
of such material, suitable for temperatures up to 800.degree. F.,
is "Duraseal 1533", commercially available from Cotronics
Corporation of Brooklyn, N.Y.
[0027] The filler material 62 of the framework 55 may not be
appropriate for contact with a seal (not specifically shown) of the
discontinuously rotating regenerator. Therefore, in embodiments
where this is an issue, the regenerator wheel 50 further includes
at least one seal face 70 made from a material appropriate for
contact with the seal of the discontinuously rotating regenerator.
Seal face 70 may be disposed to be coplanar with face 20 or may be
simply attached thereto, in the event that the regenerator seal
mechanism (not shown) is so configured.
[0028] Another exemplary process for assembly of the regenerator
wheel 50 includes positioning each of the plurality of matrixes 60
into a mold, in the appropriate port 66 location. The process
further includes introducing into the mold the framework 55 filler
material 62 through a foaming technique for open cell ceramic foam,
thereby providing the regenerator wheel 50 having the plurality of
matrixes 60 disposed within the plurality of ports 65 of the
framework 55 with a single foamed bonding structure. In a further
embodiment, the open cell ceramic foam is machined to receive the
matrices 60 at the port sections 65 and an appropriate binder
fulfilling the substantially uniform thermal expansion coefficient
is applied.
[0029] Referring now to FIG. 2 a side section view of another
embodiment of the regenerator wheel 50 is depicted. The framework
55 includes a set of side plates 80 that include the plurality of
ports 65 in which the plurality of matrixes 60 are disposed. At
least one matrix 61 is disposed within a corresponding set of the
plurality of ports 65, such as holes within each side plate 81, 82
of the set of side plates 80. Each port 66 includes geometry that
is complementary to that of the matrix 61, to accommodate disposal
of the matrix 61 within the port 66. One or more spacers 85 may be
disposed between the two side plates 81, 82 to provide an
appropriate structural integrity and external dimensions of the
regenerator wheel 50 for interface with seals of the
discontinuously rotating regenerator. The side plates 81, 82 may be
integrated with the one or more spacers 85 via at least one of an
adhesive bonding, mechanical fasteners, and welding, for example.
The matrix 61 is retained within the port 66 by a ceramic binder or
another appropriate binding material for the chosen material
combination of the matrix 61 and the side plates 81, 82. In an
exemplary embodiment, at least one of the side plates 81, 82 and
the ceramic binder is the same material as the matrix 61, to
provide substantially uniform thermal expansion, as described
above. In one embodiment the matrixes 61 in each port are of a size
greater than the flow passage. The additional matrix material
serves as insulation to prevent thermal losses to the
environment.
[0030] Referring now to FIG. 3, another embodiment of the
regenerator wheel 50 is depicted. The side plates 81, 82 include a
set of axial retention features 90, such as a step within the side
plates 81, 82 to retain the matrix 61 within the port 66. The
matrix 61 includes a corresponding set of axial retention features
91, such as a step included on the matrix 61, for example.
Accordingly, the matrix 61 can be retained within the side plates
81, 82 absent a bonding material, such as the ceramic binder. In an
exemplary embodiment, there is a minimal clearance between the port
66 and the matrix 61, thereby allowing the matrix 61 to be a
floating matrix 61, or free to translate in an axial direction
within limits established by the axial retention features 90, 91,
such as along a centerline 95 within the set of side plates 80, for
example.
[0031] Referring now to FIGS. 4 and 5, section views of another
embodiment are depicted. The framework 55 includes the two side
plates 81, 82, a non-permeable circumferential plate 96 (also
herein referred to as a "boundary plate"), and rigid, non-permeable
segmentation plates 97 (also herein referred to as "separator
plates") which are interconnected in a hub 98. The circumferential
plate 96 defines an outer boundary of the wheel 50 and is disposed
between outer edges of the set of side plates 81, 82, thereby
defining an open space between the side plates 81, 82 and within
the circumferential plate 96. The segmentation plates 97 are
disposed within the open space and create separated segments 99
that define the ports 65 into which the matrix material can be
disposed.
[0032] In one embodiment, the side plates 81, 82 are made of a
ceramic honeycomb including axial passages that allow flow of the
target species, and segmentation plates 97 are solid ceramic, to
prevent flow of the target species between the separated segments
99. In another embodiment the matrix material used to fill segments
99 is one of the ceramic foam (aforementioned) and a cloth-like
heat transfer material. One example of the cloth-like heat transfer
material is "Nextel 312", commercially available from TMO
Thermostatic Industries, Inc. of Huntington Park, Calif. The matrix
material (disposed within segments 99) can be rigidized and/or
bonded to at least one of the segmentation plates 97 and the
circumferential plate 96 by commonly used methods.
[0033] Segmentation plates 97 prevent flow in a circumferential
direction between segments 99 thereby allowing use of at least one
of the cloth-like and foamed matrix structure, which do not have
strictly axial passages. This latter arrangement will potentially
lower the weight of the ceramic matrix significantly for
continuously and discontinuously rotated regenerators. In one
embodiment, the segmentation plates 97 are a one piece, unitized
structure. While a shape of the segments 99 has been depicted as
pie shaped, it will be appreciated that the scope of the invention
is not so limited to these shapes and the invention will also apply
to regenerator apparatuses having other shapes, such as round
segments, for example.
[0034] FIG. 6 depicts another embodiment in which the side plate
81, circumferential plate 96, segmentation plates 97, and hub 98
are machined out of a ceramic honeycomb cylinder which might itself
comprise an assembly of several bonded blocks of extrusions,
thereby providing a unitized framework 55 structure. The hub 98 is
an interconnection of segmentation plates 97.
[0035] In another embodiment, as depicted in FIG. 7, the framework
55 includes a unitized circumferential plate 96, segmentation
plates 97, and the hub 98, (absent the side plates 81, 82) to form
an open framework 55. The hub 98 can fill a volume or have a mass
of its own, at the center of the framework 55. Segments 99 are
filled with ceramic cloth which is rigidized and then cut off at
the front and back by an appropriate means, such as a saw or laser
for example, thereby eliminating a need for side plates 81, 82. At
least a portion of the front and the back of the ceramic cloth
shall be rigidized to provide appropriate structural rigidity to
interface with the flow feeds, however a full depth, through the
thickness of the ceramic cloth, need not be rigidized.
[0036] While an embodiment has been described as rotatably disposed
about a center, it will be appreciated that the scope of the
invention is not so limited, and that the invention will also apply
to regenerator apparatuses that transport the matrix from one fluid
flow stream to another via alternate motion, such as linear or
curve linear translation, for example.
[0037] While an embodiment has been depicted having four distinct
ports 65, it will be appreciated that the scope of the invention is
not so limited, and that the invention will also apply to
regenerator wheels 50 having other numbers of distinct ports 65,
such as two, three, five, or more, for example. While an embodiment
has been described having steps as axial retention features, it
will be appreciated that the scope of the invention is not so
limited, and that the invention will also apply to regenerator
wheels 50 that may have other axial retention features, such as a
groove with snap rings, for example to retain the port 66 within
the side plates 80 of the carrier 55.
[0038] While the invention has been described with reference to an
exemplary embodiment or embodiments, it will be understood by those
skilled in the art that various changes may be made and equivalents
may be substituted for elements thereof without departing from the
scope of the invention. In addition, many modifications may be made
to adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this invention, but that the invention will include
all embodiments falling within the scope of the claims.
* * * * *