Patent Application
20100059206
Not applicable.
The embodiments of the present invention satisfy the need of having an insulating apparatus utilizing a quantity of water for thermal transfer and thermal mass.
Information relevant to attempts to address these problems can be found in U.S. Pat. Nos. 4,913,985 and 5,316,872; which patents are not admitted to be prior art with respect to the present invention by its mention in this Background Section. However, it is desirable to have a better device than is disclosed in the references.
In overview, the present invention includes an insulating apparatus utilizing a quantity of water for thermal transfer and thermal mass, said apparatus comprising:
In an alternate embodiment, a hollow water-filled fin extends into the main chamber, connected to the small chamber by at least two water hoses, thereby extending the water from the small chamber.
In an alternate embodiment, the water in the upper small chamber is in a water container made from a material selected from the group consisting of sheet vinyl, sheet polyurethane and sheet polyethylene. Optimally the water container sits in thermal contact with the ceiling and with the top of the upper small chamber. The water container can be a tube made from sheet vinyl, sheet polyurethane or sheet polyethylene.
In the preferred embodiment, the upper small chamber is lined with a water-proof material. In the preferred embodiment the water-proof lining is spray-on polyurethane.
The water in the upper small chamber comprises a simple thermosiphon. As the water in the bottom of the small chamber heats, it expands, becomes more buoyant and rises. In other words the heat both causes the fluid motion upwards and is itself advected upwards or carried by the fluid upwards, a process referred to as natural convection or free convection. As the heated water rises it is simultaneously replaced by colder water returning by gravity from above. The heated water loses its heat through the top of the enclosure to the sky. In hotter days this loss through the top occurs only at night, through a process referred to as night sky cooling.
These and other features, aspects and advantages of the embodiments of the device and/or methods will become better understood with reference to the following description, appended claims and accompanying drawings where:
As shown in
The enclosure 10 comprises a housing 13 insulated with insulating panels 11 in the walls and floor to inhibit heat transfer into it during the day. The ends of four of these insulating panels 11 are set on the floor 12 of the housing 13 and their sides are situated adjacent to the interior walls of the housing 13. These lower insulating panels 11 adjacent to the walls do not extend from the floor 12 to the top 30 of the housing 13. Rather they end at least eight inches from the top 30 of the housing 10. In the preferred embodiment the insulating panels 11 are made of two-inch thick styrofoam. In other embodiments, it is possible to use other modes of insulating besides the insulating panels, such as standard fiberglass wall insulation in houses.
A ceiling 20 is placed into the enclosure 10 at least eight inches from the top 30 of the housing 13 and positioned over the top of the main chamber 40 of the enclosure 10. In the preferred embodiment, the ceiling 20 sits on the tops of the insulating panels 11 that are adjacent to the walls, thereby creating an upper small chamber 70 in the top 75 of the main chamber 40; in other embodiments using other modes of insulating besides the insulating panels, the ceiling may sit on supports other than insulating panels. The ceiling 20 does not contact the walls of the housing 13, thereby ensuring a thermal break between the ceiling 20 and the housing 13, which prevents the ceiling 20 from conducting heat from the outside of the enclosure 10. An upper set of insulating panels 11 sits on the ceiling adjacent to the walls. These panels 11 extend to the top of the upper small chamber 70. Again, in other embodiments, it is possible to use other modes of insulating besides the insulating panels, such as standard fiberglass wall insulation in houses.
In the preferred embodiment, the inside of the upper small chamber 70 is made capable of holding water. The preferred embodiment uses spray-on polyurethane as used on truck bedliners and tank liners, and in roofing. Preferably the only place the water contacts the housing 13 is on top of the main chamber 75 and the inside of the lid 120 of the enclosure 10.
In an alternative embodiment, a flexible water-proof container 111 is placed inside of the upper small chamber 70 and kept in thermal contact with the ceiling 20 and with the top 100 of the small chamber 70. The water-proof container 111 is made of a material selected from the group consisting of sheet vinyl, sheet polyurethane and sheet polyethylene. It is necessary that this water container 111 be in thermal contact with the insulating panels 11 in the upper small chamber. The water container 111 can be made from a tube made from sheet vinyl, sheet polyurethane or sheet polyethylene.
The ceiling 20 allows the water 110 in the upper small chamber 70 to be in thermal contact with the lower main chamber 40. Thermosiphoning occurs in the water 110 in the upper small chamber 70 at temperatures above 45 degrees Fahrenheit, drawing heat from the lower main chamber 40 into the water 110 in the upper small chamber 70, and then to the water at the top of the upper small chamber 70 at the top of the small chamber 100 and at the top of the enclosure 30.
An insulating panel 11 is placed horizontally into the small chamber 70. This insulating panel 11 is proportional to the small chamber 70: it must be small enough that most of the small chamber 70 can be filled with water 110, it must be capable of floating in and on the water 110, and it must fit between the insulating wall panels 11. The insulating panel 11 has a spacer or spacers 15 on its top surface 97 to allow water 110 to circulate above it but under the top 100 of the small chamber 70. This allows the water 110 to be in thermal contact with the top of the housing 30 or the lid 120, white still insulating the bulk of the water 110 from the heat on the top of the housing 30. Alternatively, as shown in
The small chamber 100 is then filled with water 110, covered with a lid 120 and seated by a fastening means 60 selected from the group consisting of screws, rivets, nuts and bolts, and clamps. The top of the housing 30 is optionally formed with a one inch flange extending at right angles with holes for screws, on which flange the lid 120 is placed and attached. A gasket is optionally placed between the lid 120 and the top of the housing 30. Optionally the lid 120 has two cross breaks formed by bends along the diagonals to form a bulge 31 in the approximate center. The bulge 31 gives the lid a high point where an air bubble can form, preventing the loss of wet surface area across the rest of the lid. On the bulge may be placed a fill cap 32, which is gasketed and water tight.
The water 110 must be in thermal contact with the outside of the lid 120 of the enclosure 30 to allow for thermal exchange between the water 110 and the ambient environment. During the day the water 110 in the small chamber 70 absorbs the heat building up inside the main chamber 40. At night the heat from the water 110 dissipates out the lid 120 of the enclosure 30 to the ambient environment.
A hollow water-filled fin 130 or other radiator may optionally extend into the main chamber 40, connecting the small chamber by at least two water hoses 131. This fin 130 will facilitate the thermal transfer from the main chamber 40 into the water 110 in the small chamber 70.
In a hot environment where ambient temperatures never drop below 45 degrees F., during the day the side insulating panels 11 mitigate the absorption of heat from solar radiation impinging on the outside of the enclosure 10. The thermal mass of cooler water 110 in the adjacent upper small chamber 70 acts as a heat sink, drawing and absorbing heat from the lower main chamber 40. Some thermal stratification occurs in the water 110 in the upper small chamber 70: the water 110 absorbing the heat from the lower main chamber 40 is in the bottom of the upper small chamber 98, adjacent to the lower main chamber 40. The insulating panel 11 floating in the top of the small chamber 100 mitigates the absorption of heat from solar radiation impinging on the top of the enclosure 10. At night, the night sky serves as a heat sink. As ambient temperature cools, the hot water in the bottom of the small chamber 98 travels to the top of the small chamber 100, where it dissipates to the night sky.
In embodiments in which the enclosure contains a battery or batteries or otherwise requires venting to the exterior, the enclosure will have a vent or vents to the exterior. In the case of the diffusive vent, these vents will be covered, for example with cardboard or other paper-based materials. The primary venting mechanism however will be the convective vent, comprising two tube openings at the top of one side of the enclosure, where the other ends of each tube extends through the sidewall to the opposite side of the enclosure and then drop to within a few inches of the floor of the enclosure.
A plurality of upper small chambers 70 can be placed adjacent to one another over a single main chamber 40. For example the sides of the upper small chambers 70 can be defined by roof joists in the attic of a residential house or of a commercial building, or by ceiling joists in a single joist construction without an attic. In other words, either the attic joist space or the ceiling joist space comprises the upper small chambers 70. The lower main chamber 40 can be the attic such that the invention most directly coots the attic, or the lower main chamber 40 can be the living space or working space proper such that the invention most directly coots the main interior space of the structure. The roof joists can be “I”-shaped (such as a TJI Joist™) where the top of the joist abuts the bottom side of the roof above, and the bottom of the joist sits on the upper side of the ceiling or false ceiling below.
The embodiments of the invention further comprise a method for manufacturing an insulating apparatus utilizing a quantity of water for thermal transfer and thermal mass, said method comprising:
Optionally, the method for manufacturing further comprises the step of providing a hollow water-filled fin extending from the small chamber into the main chamber, said fin sharing water with said small chamber.
Optionally, the water in the small chamber is in a water container made from a material selected from the group consisting of sheet vinyl, sheet polyurethane and sheet polyethylene.
Optionally, the water container sits in thermal contact with the ceiling and with the inside surface of said top of said housing.
Optionally, the water container is a tube made from sheet vinyl, sheet polyurethane or sheet polyethylene.
Optionally, the method for manufacturing further comprises the step of lining the small chamber with a water-proof material.
Optionally, said water-proof material is spray-on polyurethane.
Optionally, the housing is an outdoor equipment enclosure.
Optionally, the internal chamber is a human-occupied structure and the housing is a residential or commercial building.
Some Advantages of the Embodiments of the Invention
The advantages of the embodiments of the invention include but are not limited to providing a means for passive thermal control over an enclosure. Every advantageous feature does not need to be incorporated into every embodiment of the apparatus and/or methods.
Although these versions of the invention have been described in considerable detail, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the versions contained therein.
This application claims the benefit of provisional application 61/096,002 filed Sep. 11, 2008.
| Number | Date | Country | |
|---|---|---|---|
| 61096002 | Sep 2008 | US |
