Heat exchange – Regenerator – Heat collector
Reexamination Certificate
2002-02-21
2004-08-10
McKinnon, Terrell (Department: 3743)
Heat exchange
Regenerator
Heat collector
C165S902000, C126S641000, C062S430000
Reexamination Certificate
active
06772823
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a heat storage device for temporarily storing heat.
DESCRIPTION OF THE RELATED ART
Basic constructions of conventional heat storage devices are illustrated in
FIGS. 11 through 13
in the form of sectional views.
A heat storage device shown in
FIG. 11
comprises a heat storage tank
32
charged with a heat storage material
31
such as water, and a heat exchanger
33
disposed in the heat storage tank
32
, for executing a heat exchange with the outside. In order to store the heat of, for example, a temperature T
x
within this heat storage device, the temperature of the heat storage material
31
is raised to T
x
by adding the heat of a temperature of at least T
x
to the heat exchanger
33
from the outside. When heat is needed at the outside, the heat of the temperature T
x
is extracted from the heat storage material
31
to the outside, using the heat exchanger
33
.
A heat storage device as shown in
FIG. 12
comprises heat storage tanks
42
a
and
42
b
charged with a heat transfer medium
47
such as water which also serves as a heat storage material for storing heat, wherein the heat storage tank
42
a
has a communicating tube
44
a
for connecting the heat storage tank
1
with the outside, wherein the heat storage tanks
42
a
and
42
b
are connected by a communicating tube
44
b
, and wherein the heat storage tank
42
b
has a communicating tube
44
c
for connecting the heat storage tank
42
b
with the outside.
In the operation of this heat storage device, in order to store the heat of, for example, a temperature T
x
, the heat transfer medium
47
is sucked out from the communicating tube
44
c
, and the temperature of the heat transfer medium
47
is raised to at least T
x
by adding heat to the heat transfer medium
47
at the outside, then the heat transfer medium
47
being injected from the communicating tube
44
a
to the heat storage tanks
42
a
. The heat transfer medium
47
removed from the heat storage tank
42
a
by this injection, arrives at the heat storage tanks
42
a
passing through the communicating tube
44
a
. After a while, the heat transfer medium
47
is sucked out from the communicating tube
44
c
, and executes a heat transport between the heat storage tank
42
and the outside, then returning to the heat storage tank
42
a
again passing through the communicating tube
44
a
. Thus, a circulation of the heat transfer medium
47
is accomplished. If heat is needed at the outside, a process in the opposite direction to the injection process of heat is executed. That is, the heat transfer medium
47
is sucked out from the communicating tube
44
a
, and heat is absorbed and utilized at the outside, and the heat transfer medium
47
of which temperature has decreased as a result of the absorption and utilization of heat, is returned from the communicating tube
44
c
to the heat storage tank
41
b
. Due to this returning, the heat transfer medium
47
removed from the heat storage tanks
42
b
flows into the heat storage tank
42
a
passing through the communicating tube
44
b
. Thus, a circulation of the heat transfer medium
47
is accomplished.
An object of suitably dividing the heat storage tank is to suppress the occurrence of a dead water region where flow is apt to stagnate within the heat storage tank, and to allow the circulation of the heat transfer medium
47
in injecting and extracting heat to be uniformly conducted by using the whole of the heat storage tank.
If the heat of a lower temperature than an ambient temperature is stored, the directions of flow of the heat transfer medium
47
in the processes of injection and extraction will be opposite to each other. However, the basic operation is similar to the foregoing.
On the other hand, in a heat storage device shown in
FIG. 13
, a heat storage material
51
utilizing mainly transition heat is charged into small vessels
56
, which are accommodated in the heat storage tank
52
, and the heat storage tank
52
is provided with communicating tubes
55
a
and
55
b
for making the heat storage tank
52
communicate with the outside. By the heat transfer medium
57
which circulates through these communicating tubes
55
a
and
55
b
and the heat storage tank, heat exchange means for executing a heat exchange with the outside is constituted. In this case, the storage of heat is mainly executed by the heat storage material
51
which utilizes a transition heat. Although the heat transfer medium
57
functions as heat transport means, it does not mean that the heat transfer medium
57
does not participate in the storage of heat.
In this heat storage device, in order to store the heat of, for example, a temperature T
x
, the heat transfer medium
57
having a temperature of at least T
x
is injected from the outside to the heat storage tank
52
through the communicating tube
55
a
. The heat storage material
51
is heated by the heat which has been released by the heat transfer medium
57
via the walls of the small vessels
56
. The heat transfer medium
57
injected returns to the outside passing through the communicating tube
55
b
, and is again heated to a temperature of at lease T
x
. Thus, a similar circulation is repeated. If heat is needed at the outside, a process in the opposite direction to the process of heat injection is executed. That is, the heat transfer medium
57
is injected from the outside to the heat storage tank
52
through the communicating tube
55
b
. The heat transfer medium
57
injected is heated by the heat released by the heat transfer medium
51
, via the walls of the small vessels
56
. The heat transfer medium
57
heated returns to the outside passing through the communicating tube
55
a
, and its temperature becomes lower than T
x
as a result of the utilization at the outside, then being injected again. Thus, a similar circulation is repeated. Also in the case where the heat of a lower temperature than the ambient temperature is stored, the basic operation is similar to the foregoing.
In this example of constitution, since the heat transfer medium
57
which is injected and extracted from the outside passes through the gaps between the small vessels, the area of a heat transfer surface to the heat storage material
51
becomes large, as well as the treatment of the heat storage material
51
becomes easy, and hence such a constitution is often used for heat storage devices that use paraffin as a heat storage material
51
which utilizes transition heat.
In the above-described heat storage devices shown in
FIGS. 11 through 13
, in the state of heat storage, if there are temperature differences between the heat storage materials
31
,
51
, and the heat transfer medium
47
which also serves as a heat storage material, and the external environment surrounding the heat storage tanks
32
,
42
, and
52
, then heat transfer always takes place between the heat storage devices and the external environment through the wall surfaces of heat storage tanks
32
,
42
, and
52
, respectively.
Neglecting the influence of heat radiation which is usually low, the heat loss Q of a heat storage material or a heat transfer medium which also serves as a heat storage material (hereinafter these are both referred to as a heat storage material) is expressed by the following equation.
Q=
kA
(
Tx′−T
0
)
dt [J]
(1)
Here, k denotes an overall heat transfer coefficient determined by the material, construction, and ambient air speed of a heat storage tank, etc. A denotes a contact area between a heat storage tank and a ambient fluid (such as air). T
0
represents an environmental temperature outside the heat storage device, and T
x
′ represents a temperature at the surface where the heat storage material contacts the heat storage tank (the surface of heat storage material), t representing an elapsed time. Since k and A can usually be regarded as constants irrespective of time, the equation (1) may be expressed approximately as follows:
Q=kA
(
Tx′&
Agency of Industrial Science and Technology
McKinnon Terrell
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
LandOfFree
Heat storage device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heat storage device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heat storage device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3286227