U.S. patent application number 13/015790 was filed with the patent office on 2012-08-02 for water heater with counter-twisted baffle.
Invention is credited to J. Eric Arnold, John L. Dreher, George W. Kraus, Ramin K. Rahmani, Roger D. Veen, Stephen J. Werfel.
Application Number | 20120192812 13/015790 |
Document ID | / |
Family ID | 46576282 |
Filed Date | 2012-08-02 |
United States Patent
Application |
20120192812 |
Kind Code |
A1 |
Rahmani; Ramin K. ; et
al. |
August 2, 2012 |
WATER HEATER WITH COUNTER-TWISTED BAFFLE
Abstract
A water heater including a storage tank, a combustion chamber, a
burner for producing products of combustion, the burner positioned
in the combustion chamber, a flue extending from the combustion
chamber through the storage tank, and a baffle positioned within
the flue and directing the flow of the products of combustion
through the flue. The baffle includes multiple clockwise twist
segments and multiple counterclockwise twist segments.
Inventors: |
Rahmani; Ramin K.; (Johnson
City, TN) ; Kraus; George W.; (Johnson City, TN)
; Veen; Roger D.; (Telford, TN) ; Werfel; Stephen
J.; (Johnson City, TN) ; Arnold; J. Eric;
(Jonesborough, TN) ; Dreher; John L.; (Johnson
City, TN) |
Family ID: |
46576282 |
Appl. No.: |
13/015790 |
Filed: |
January 28, 2011 |
Current U.S.
Class: |
122/15.1 |
Current CPC
Class: |
F24H 9/0026 20130101;
F24H 1/205 20130101; F28F 13/12 20130101; F28F 13/06 20130101; F28D
21/0007 20130101 |
Class at
Publication: |
122/15.1 |
International
Class: |
F24D 19/00 20060101
F24D019/00 |
Claims
1. A water heater, comprising: a storage tank; a combustion
chamber; a burner for producing products of combustion, the burner
positioned in the combustion chamber; a flue extending from the
combustion chamber through the storage tank; and a baffle
positioned within the flue and directing the flow of the products
of combustion through the flue, the baffle including a plurality of
clockwise twist segments and a plurality of counterclockwise twist
segments.
2. The water heater of claim 1 wherein the baffle further includes
a longitudinal axis and wherein the clockwise twist segments
alternate with the counterclockwise twist segments along the
longitudinal axis.
3. The water heater of claim 1 wherein each of the clockwise twist
segments twists one hundred eighty degrees and wherein each of the
counterclockwise twist segments twists one hundred eighty
degrees.
4. The water heater of claim 1 wherein the baffle is
corrugated.
5. The water heater of claim 1 wherein the baffle further includes
a longitudinal axis and wherein the length along the longitudinal
axis of at least one of the clockwise twist segments varies with
respect to the other clockwise twist segments and wherein the
length along the longitudinal axis of at least one of the
counterclockwise twist segments varies with respect to the other
counterclockwise twist segments.
6. The water heater of claim 2 wherein each of the clockwise twist
segments twists one hundred eighty degrees and wherein each of the
counterclockwise twist segments twists one hundred eighty
degrees.
7. The water heater of claim 6 wherein the baffle is
corrugated.
8. The water heater of claim 7 wherein the length along the
longitudinal axis of at least one of the clockwise twist segments
varies with respect to the other clockwise twist segments and
wherein the length along the longitudinal axis of at least one of
the counterclockwise twist segments varies with respect to the
other counterclockwise twist segments.
9. The water heater of claim 6 wherein the length along the
longitudinal axis of at least one of the clockwise twist segments
varies with respect to the other clockwise twist segments and
wherein the length along the longitudinal axis of at least one of
the counterclockwise twist segments varies with respect to the
other counterclockwise twist segments.
10. The water of claim 9 wherein a spacer is positioned between an
adjacent clockwise twist segment and counterclockwise twist
segment, wherein the clockwise twist segments are corrugated, and
wherein the counterclockwise twist segments are corrugated.
11. The water heater of claim 2 wherein the baffle is
corrugated.
12. The water heater of claim 2 wherein the length along the
longitudinal axis of at least one of the clockwise twist segments
varies with respect to the other clockwise twist segments and
wherein the length along the longitudinal axis of at least one of
the counterclockwise twist segments varies with respect to the
other counterclockwise twist segments.
13. The water heater of claim 2 wherein a spacer is positioned
between an adjacent clockwise twist segment and counterclockwise
twist segment.
14. The water heater of claim 13 wherein the clockwise twist
segments are corrugated and wherein the counterclockwise twist
segments are corrugated.
15. A baffle for use in the flue of a water heater to direct the
flow of products of combustion through the flue, the baffle
comprising: a plurality of clockwise twist segments; and a
plurality of counterclockwise twist segments.
16. The baffle of claim 15, the baffle further comprising a
longitudinal axis and wherein the clockwise twist segments
alternate with the counterclockwise twist segments along the
longitudinal axis.
17. The baffle of claim 16 wherein each of the clockwise twist
segments twists one hundred eighty degrees and wherein each of the
counterclockwise twist segments twists one hundred eighty
degrees.
18. The baffle of claim 15 wherein each of the clockwise twist
segments twists one hundred eighty degrees and wherein each of the
counterclockwise twist segments twists one hundred eighty
degrees.
19. The baffle of claim 15 wherein the baffle is corrugated.
20. The baffle of claim 15 the baffle further comprising a
longitudinal axis and wherein the length along the longitudinal
axis of at least one of the clockwise twist segments varies with
respect to the other clockwise twist segments and wherein the
length along the longitudinal axis of at least one of the
counterclockwise twist segments varies with respect to the other
counterclockwise twist segments.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to water heaters, and more
particularly to water heaters including flue baffles.
[0002] A flue baffle is positioned in the flue tube of a gas-fired
water heater. A burner combusts a fuel and air mixture to create
products of combustion or exhaust gases. The gases flow through the
flue tube to heat the water stored in a tank. The baffle enhances
the heat exchange rate between the gases and the water stored in
the tank.
SUMMARY OF THE INVENTION
[0003] The present invention provides, in one aspect, a water
heater including a storage tank, a combustion chamber, a burner for
producing products of combustion, the burner positioned in the
combustion chamber, a flue extending from the combustion chamber
through the storage tank, and a baffle positioned within the flue
and directing the flow of the products of combustion through the
flue. The baffle includes multiple clockwise twist segments and
multiple counterclockwise twist segments.
[0004] The present invention provides, in another aspect, a baffle
for use in the flue of a water heater to direct the flow of
products of combustion through the flue. The baffle includes
multiple clockwise twist segments and multiple counterclockwise
twist segments.
[0005] Other features and aspects of the invention will become
apparent by consideration of the following detailed description and
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a perspective view of a water heater.
[0007] FIG. 2 is a perspective view of a baffle of the water heater
of FIG. 1.
[0008] FIG. 3 is a front view of the baffle of FIG. 2.
[0009] FIG. 4 is a side view of a portion of a sheet used to form
the baffle of FIG. 1.
[0010] FIG. 5 is a front view of a second embodiment of a
baffle.
[0011] Before any embodiments of the invention are explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangement
of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways. Also, it is to be understood that the phraseology and
terminology used herein is for the purpose of description and
should not be regarded as limiting.
DETAILED DESCRIPTION
[0012] FIG. 1 illustrates a water heater 100 including a base pan
105, a tank 110 supported by the base pan 105 and containing water,
an insulating jacket 115 surrounding the tank 110, and a burner
120. A flammable fuel is provided to the burner 120 by a fuel inlet
125 connected to a fuel valve 130. The burner 120 is positioned in
a combustion chamber 135 beneath the tank 110. The fuel valve 130
is connected to a fuel supply. The fuel can be, for example,
natural gas or propane. The combustion chamber 135 is connected to
an air supply, for example, the atmosphere around the water heater
100. A flue tube 140 extends from the combustion chamber 135
through the tank 110. The flue tube 140 includes a central
longitudinal axis 145. The products of combustion or exhaust gases
created by the burner 120 flow through the flue tube 140 to heat
the water stored in the tank 110. A cold water inlet pipe 150
supplies cold water to the tank 110. A hot water supply pipe 155
supplies hot water to an end-use location, for example, a faucet.
The water heater 100 as described above is conventional.
[0013] As shown in FIG. 1, a baffle 160 is positioned within the
flue tube 140. A hanger or cross-bar 165 supports and positions the
baffle 160 within the flue tube 140. In some embodiments, other
suitable means are used to support and position the baffle 160
within the flue tube 140. The baffle 160 extends longitudinally
within the flue tube 140. Preferably, a central longitudinal axis
170 of the baffle 160 is collinear with the longitudinal axis 145
of the flue tube 140. The baffle 160 is positioned within the flue
tube 140 to leave a space 172 between the lower end of the baffle
160 and the lower end of the flue tube 140. The space 172
facilitates mounting the flue tube 140 and baffle 160 on a glass
coating machine that coats the inside and outside of the flue tube
140 and the baffle 160 with a protective coating to resist
degradation or corrosion of the flue tube 140 and baffle 160. Also,
the space 172 makes the baffle 160 less likely to be overheated by
extreme temperatures in the combustion chamber 135. The space 172
can be, for example, about three inches (7.62 centimeters) in
length but such length may vary based on manufacturing parameters.
In other embodiments, the lower end of the baffle 160 is flush with
the lower end of the flue tube 140.
[0014] As shown in FIGS. 2-3, the baffle 160 includes six clockwise
twist segments or twists 175 and six counterclockwise twist
segments or twists 180 that alternate with each other along the
longitudinal axis 170 of the baffle 160 so that each clockwise
twist 175 is adjacent to a counterclockwise twist 180. A
substantially flat or planar spacer 190 is positioned between each
adjacent clockwise twist 175 and counterclockwise twist 180. Each
spacer 190 is positioned in a vertical plane that includes the
longitudinal axis 170. The length of each spacer 190 along the
longitudinal axis 170 can vary as necessary. Preferably, the length
of a spacer is 0.36 inches (0.91 centimeters). Preferably, each
clockwise twist 175 is a one hundred eighty degree twist and each
counterclockwise twist 180 is a one hundred eighty degree twist.
That is, a sheet or plate 195 is twisted clockwise one hundred
eighty degrees about the longitudinal axis 170 to form a clockwise
twist 175 and then the same sheet is twisted counterclockwise one
hundred eighty degrees about the longitudinal axis 170 to form a
counterclockwise twist 180. The length of each clockwise twist 175
along the longitudinal axis 170 is substantially the same and the
length of each counterclockwise twist 180 along the longitudinal
axis 170 is substantially the same. In some embodiments, each
clockwise twist 175 is twisted more or less than one hundred eighty
degrees and each counterclockwise twist 180 is twisted more or less
than one hundred eighty degrees. For example, each twist 175 and
180 could be twisted ninety degrees or three hundred sixty degrees.
More or fewer twists 175 and 180 can be included as necessary.
Preferably, the baffle has a diameter of 3.625 inches (9.207
centimeters) and an overall length of 45.25 inches (114.9
centimeters), the length along the longitudinal axis 170 of each of
the twists 175 and 180 is between three inches (7.62 centimeters)
and six inches (15.24 centimeters), and the flue tube 140 has a
diameter of four inches (10.16 centimeters). In some embodiments, a
spacer 190 is not positioned between each adjacent clockwise twist
175 and counterclockwise twist 180. In other embodiments, the
spacer 190 is corrugated.
[0015] As shown in FIGS. 1-3, the baffle 160 is corrugated. FIG. 4
shows a side view of a portion of the sheet 195 used to form the
baffle 160 before the sheet 195 is twisted. The sheet 195 includes
an alternating series of peaks 200 and valleys 205 that form the
corrugations. Alternatively, the baffle 160 is manufactured from a
substantially flat or planar sheet or plate. The sheet 195 can be
manufactured of mild (i.e., low carbon) steel, stainless steel,
Inconel.RTM., nickel alloy, or other suitable materials. For
example, the baffle 160 can be cold formed from a steel sheet 195.
However, cold forming a steel sheet 195 limits how short of a twist
length can be formed for each of the twists 175 and 180. It is to
be understood that other processes and/or methods of processing a
material to form the baffle 160 fall within the scope of the
invention. For example, the clockwise twists 175 and the
counterclockwise twists 180 can be formed individually and then
secured together, for example, by welding, brazing, or
soldering.
[0016] FIG. 5 shows an alternative baffle 360 similar to the baffle
160. Components similar to those of the baffle 160 described above
are numbered in a similar fashion plus two hundred. The baffle 360
has a varying pitch so that the length of at least one of the
clockwise twists 375 along the longitudinal axis 370 varies with
respect to the length of a different one of the clockwise twists
375 and so that the length of at least one of the counterclockwise
twists 380 along the longitudinal axis 370 varies with respect to
the length of a different one of the counterclockwise twists 380.
The baffle 360 includes three groups 210, 215, and 220 of twists
375 and 380. In the first group 210, the lengths of each of the
clockwise twists 375 and the counterclockwise twists 380 are a
first length. In the second group 215, the lengths of each of the
clockwise twists 375 and the counterclockwise twists 380 are a
second length different than the first length. In the third group
220, the lengths of each of the clockwise twists 375 and the
counterclockwise twists 380 are a third length different than both
the second length and the first length. Preferably, the first
length is three inches (7.62 centimeters), the second length is
four inches (10.16 centimeters), and the third length is five
inches (12.7 centimeters). More or fewer groups of twists 375 and
380 of the same length can be used as necessary. The number of
twists 375 and 380 in a group can vary and a group can consist of a
single twist 375 or 380.
[0017] In use, the burner 120 combusts a fuel and air mixture to
create products of combustion or exhaust gases. The gases exit the
combustion chamber 135 and enter the lower end of the flue tube
140. As the gases encounter the baffle 160, the gases are directed
in a circuitous path along the alternating clockwise twists 175 and
counterclockwise twists 180. The alternating clockwise twists 175
and counterclockwise twists 180 create tangential and radial
movement of the gases which increases both the amount of contact
between the gases and the wall of the flue tube 140 and the
turbulent kinetic energy of the gases. These in turn increase the
heat transfer rate between the gases and the water stored in the
tank 110. Additionally, the twists 175 and 180 increase the
residence time of the gases within the flue tube 140, which also
increases the heat transfer rate. The corrugations of the baffle
160 improve the radiative heat transfer when compared to a
non-corrugated baffle. Also, the corrugations increase the amount
of turbulent flow in the gases, which increases the convective heat
transfer when compared to a non-corrugated baffle. Enhancing the
heat transfer rate between the gases and the water stored in the
tank 110 improves the energy factor (EF) of the water heater 100.
The baffle 160 with alternating clockwise twists 175 and
counterclockwise twists 180 significantly increases the heat
transfer rate as compared to a baffle with twists all in the same
direction. Shorter twist lengths, which result in more twists 175
and 180 for a baffle 160 of a certain length, provide the most heat
transfer enhancement. However, the pressure drop caused by the
baffle 160 along the flue tube 140 increases as the twists lengths
decrease. The baffle 360 with twists 375 and 380 of varying lengths
helps to optimize the heat transfer rate in relation to the
pressure drop. Also, the length of the spacers 190, 390 can be
varied to assist in optimizing the heat transfer rate in relation
to the pressure drop. Various features of the invention are set
forth in the following claims.
* * * * *