ABSORPTION COOLING FOR AIRCRAFT TROLLEYS AND COMPARTMENTS
Embodiments of the present invention relate generally to improved cooling systems and methods for use on aircraft trolleys and compartments. The systems use absorptive cooling with thermal conductive plates strategically positioned in order to keep trolleys and their contents cooled.
This application claims the benefit of U.S. Provisional Application Ser. No. 61/712,368, filed Oct. 11, 2012, titled “Absorption Cooling Used on Galley's Trolley Compartment,” and U.S. Provisional Application Ser. No. 61/712,370, filed Oct. 11, 2012, titled “Absorption Cooling Used on Trolley Cooling,” the entire contents of each of which are hereby incorporated by reference.
FIELD OF THE INVENTIONEmbodiments of the present invention relate generally to improved cooling systems and methods for use on aircraft trolleys and compartments.
BACKGROUNDAircraft trolleys are used to chill and maintain the temperature of food and various other items that are to be served on-board an aircraft. The trolleys are generally chilled via an airflow from an air chiller or compressor that is directed over the items in the trolley. In many instances, the trolley has an opening in the back that can be aligned with a cool air blower that causes air to flow into the trolley and around the food and beverage items contained therein. This configuration can make it difficult to move and interchange the trolleys. Improvements to these cooling systems would be beneficial.
Absorption cooling uses a heat source to drive the cooling system. For example, an absorption refrigerator is a refrigerator that uses a heat source (such as a solar source, a kerosene-fueled flame, or waste heat from factories) to provide the energy needed to drive the cooling system. In the early part of the twentieth century, the vapor absorption cycle using water-ammonia systems was widely used, but upon development of the vapor compression cycle, it lost much of its use. Absorption cooling technology has not been used for air conditioning or chilling inside aircraft.
The present inventors have determined that if an appropriate heat source could be provided, the use of absorption cooling on-board aircraft or other vehicles could be a viable alternative to the cooling that is provided by air chillers or compressors in order to recycle the heat and to reduce noise from the traditional cooling systems. Replacing an electric air chiller with an absorption cooler can also reduce electricity loads. Embodiments of the present invention thus provide absorption cooling systems for trolleys and other containers in aircraft or other vehicle galleys. In a specific embodiment, the waste heat used to power the cooling system is provided from a fuel cell, which produces heat as one its by-products. Fuel cell technology has been contemplated by the current assignee and its related companies for powering more and more aircraft systems, particularly various galley (and lavatory) systems, because it is a clean and efficient power source. However, the primary way to make fuel cell technology efficient is by using the fuel cell by-products (water, heat, and oxygen depleted air) in addition to the energy created that is created by the fuel cell. One way to use the heat created is by delivering the heat to an absorptive cooling system. It should be understood that the heat may be provided from other aircraft systems, such as waste heat from one or more of the on-board ovens, from the aircraft engines, from the water system, or any other appropriate source.
In one embodiment, there is provided a system 10 for absorptive cooling an aircraft trolley 12 or other compartment for use on board a passenger transport vehicle. As shown in
A cooling fluid circuit 26 is also provided behind the back wall of the trolley bay 20. The coolant circuit 26 is associated with the thermal plate 18 of the back wall, as well as with the absorption cooling unit. As waste heat (with a temperature generally between about 50-90 ° C., and in some instances, between 60-80° C.) is transformed by the absorption cooler, the coolant circuit 26 delivers the cooled fluid to the thermal plate 18. Its contact with the thermal plate 14 of the trolley transfers the cold to the trolley 12. Fan 22 helps recirculate cooled air inside the trolley 12. Although the Figures show a single trolley being interfaced with a single galley wall, it should be understood that the coolant circuit 26 may route cooled fluid to any number of galley bay locations such that multiple trolleys may be cooled at a time.
An adjustment system may be provided to ensure contact between the plates 14 and 18. Because the trolley has clearance and is moveable, an adjustment system may assure correct alignment of trolley to allow contact between the plates.
The schematic of
As discussed, in one aspect, thermal plate 18 on the monument aligns with a thermal plate 14 that is mounted on the back of the trolley to generate the desired cooling effect. This system uses less power than an air chiller, it uses waste heat and thus improves efficiency, it provides cooling directly in the area where it is needed, and it provides a modular principle that can be used with each trolley inside the trolley bay.
Another embodiment that uses absorptive cooling technology for chilling trolleys is shown in
The trolleys may include internal fans (as discussed above) to help move and recirculate cooled air through and over the items in the trolley to improve cooling efficiency and to create an even temperature range. External fans 40 may also be mounted to the back of the galley stowage space and are provided in order to circulate air over the trolley(s) to support the natural recirculation of air and to keep the temperature even in the trolley bay.
These embodiments can alleviate the need for a duct pipe that is typically provided at the back of the monument to deliver chiller air from the air chiller to the trolley. Providing even slight space gains can translate to major costs savings for the airline, as a few inches of space saved can mean additional passenger seats that can be added to the aircraft. One of the other benefits of the above-described solutions is that they do not require modifications to current trolley designs or sizes, nor to the current catering processes. They also reduce electricity loads on the aircraft by providing cooled air using waste heat from fuel cells or other sources.
Changes and modifications, additions and deletions may be made to the structures and methods recited above and shown in the drawings without departing from the scope or spirit of the invention and the following claims.
Claims
1. A cooling system for a trolley positioned in a galley bay, the galley bay having one or more stowage areas for trolleys, comprising:
- (a) a waste heat source;
- (b) an absorptive cooler;
- (c) a cooling fluid circuit; and
- (d) at least one thermal conductive plate positioned on at least one wall of the stowage area of the galley bay,
- wherein waste heat from the waste heat source is delivered to the absorptive cooler which uses the waste heat to drive the cooler,
- wherein the cooling fluid circuit delivers cooled fluid to the at least one thermal conductive plate, and
- wherein the at least one thermal conductive plate delivers cooling to a trolley.
2. The system of claim 1, wherein a trolley is positioned in the stowage area of the galley bay and wherein the trolley comprises a thermal conductive plate positioned on its back wall to contact the at least one thermal conductive plate on the wall of the stowage area.
3. The system of claim 1, wherein the stowage area comprises a top wall, a back wall, and a divider wall panel, wherein a thermal conductive plate is positioned on the top wall, the back wall, and the divider wall panel.
4. The system of claim 1, wherein the cooling system is used on board a passenger transport vehicle.
5. The system of claim 1, wherein the cooling system is used on board an aircraft.
6. The system of claim 1, wherein the waste heat source comprises a fuel cell.
7. A method for cooling a galley trolley stowage area, comprising
- (a) delivering heat from a heat source to an absorptive cooler;
- (b) delivering cooled fluid from the absorptive cooler through a cooling fluid circuit to at least one thermal conductive plate positioned on a wall of the galley trolley stowage area.
8. The method of claim 7, wherein the at least one thermal conductive plate is positioned on a back wall of a galley monument.
9. The method of claim 8, further comprising positioning a trolley against the back wall of the galley monument, wherein the trolley comprises a thermal conductive plate positioned on its back wall such that it contacts the at least one thermal conductive plate on the back wall of the galley monument.
10. The method of claim 7, further comprising a plurality of thermal plates positioned on walls of the galley trolley stowage area, such that the thermal plates create a cooling environment for a trolley positioned in the trolley stowage area.
11. The method of claim 10, wherein the plurality of thermal plates are positioned on a top wall of the galley monument and a divider wall panel of the galley monument.
Type: Application
Filed: Oct 11, 2013
Publication Date: Apr 17, 2014
Applicants: Commissariat à l'Energie Atomique et aux Energie Altematives (Paris), DRIESSEN AEROSPACE GROUP NV (Alkmaar)
Inventors: Jean-Paul Libis (Bievres), Franck Masset (Saint Georges Motel), Yannick Brunaux (Croix), Andreas Hoogeveen (Enkhuizen), Fredric Muyu (Herborn), Patrice Tochon (Uriage Les Bains), Jean Francois Fourmigue (Fontaine), Francois Boudehenn (Saint Sauveur De Montagut), Delphine Bourdon (St. Egreve), Stephane Colasson (Voreppe)
Application Number: 14/051,478
International Classification: F25B 15/00 (20060101);