Thermal heat management system

Abstract

Thermal heat management system The present invention discloses a thermal heat management system (1) comprising: at least one auxiliary power unit (2), at least one thermal heat exchange system (3) connected to the at least one auxiliary power unit (2), wherein the at least one thermal heat management system (1) is configured to absorb and use thermal heat from the at least one auxiliary power unit (2).

Description

[0001] Thermal heat management system

[0002] TECHNICAL FIELD

[0003] The present invention relates to a thermal heat management system that can be used in any area of use such as, for example, buildings and / or vehicles such as, for example, commercial and / or military aircraft where equipment can be activated, for example, by a passenger and / or a crew member.

[0004] Such a thermal heat management system can be used, for example, for cabin equipment and / or devices in vehicles such as, for example, an aircraft.

[0005] BACKGROUND ART

[0006] For example, an aircraft cabin hosts several individual equipment and / or individual devices which can be triggered and activated by passengers and / or by crew members. Such equipment and / or devices may generally be composed of at least one sensor, which is either a mechanical or an electrical sensor and which triggers an actuator for activating the functionalities of each individual equipment and / or each individual device.

[0007] Such equipment and / or devices might for example include a reading light integrated into a passenger service unit, or an infrared sensor designed for a water faucet, such as those found in restrooms.

[0008] Aircraft galleys comprise of many different electrical inserts like coffee maker, oven, chiller, microwave and so on, which are typically supplied with electrical power from the aircraft.

[0009] All of the before mentioned equipment and / or devices require power from the main aircraft power supply or alternatively on ground from an Auxiliary Power Unit (APU), both power supply sources produce CO2.

[0010] Thermoelectric generators utilize the Seebeck- Effect, to transfer thermal heat into electric power. These generators are in use in the automotive section, space technology, power plant area to increase the system efficiency by utilizing the waste heat.

[0011] Organic Rankine Cycle (ORC) - systems are in use in the terrestrial fields to transfer the waste heat of industrial plants, power plants or geothermal power plants into electric power. The designed ORC- systems are very heavy and bulky and designed for higher process waste heat temperatures above 100 °C. Thus the designed ORC- Systems are not adapted to lower waste heat temperatures of PEM- Fuel Cells which provide waste heat temperatures of approximately 80°C - 90°C.

[0012] PROBLEMS ASSOCIATED WITH THE PRIOR ART

[0013] The use of an APU produces CO2. In order to reduce the amount of CO2 consumption alternatives to known APUs are necessary. One possibility for such an alternative are fuel cell systems (FCS) such as, for example, a polymer electrolyte membrane (PEM) fuel cell system, which can be powered by hydrogen.

[0014] The use of hydrogen powered PEM fuel cell systems is expected to increase in an aircraft interior use in order to reduce CO2 generating power systems such as APU or power generators, for example, at aircraft engines. Actual multi-functional fuel cell systems might be installed instead of an APU and supplied by hydrogen for constant operation during operation, for example during a flight of an aircraft. Hereby, APUs, power generators or FCS generate a severe amount of thermal heat energy. PEM FCS also generate a severe amount of thermal heat energy as electrical power at about 80 - 90 °C in the range of 100 - 150 kW, which may be more thermal heat than an APU or a power generator generates. Any thermal heat load has to be cooled down, for example, by aircraft cabin heat exchange with a high amount of circulation power needed.

[0015] The thermal heat management systems and / or devices in aircraft need to be a lightweight and dimensional tiny application to be installed nearby the electrical source (fuel cell system), which emitted thermal heat from the power generation process. The thermal heat transfer is required to avoid overheating of the producing system (e.g. fuel cell system).

[0016] The thermal heat energy could be used for evaporation of liquid hydrogen in case it was designed for this use. In all further applications, for example, cabin installed FCS or smaller amounts thermal heat management systems are needed. These systems have to be scalable as the FCS itself in order to guarantee continuous operation.

[0017] TECHNICAL OBJECTIVES OF THE INVENTION

[0018] The main technical problems to be solved by the present invention are:

[0019] Reducing the thermal heat.

[0020] Increasing the functionality of the thermal heat management.

[0021] Avoid overheating. Use of thermal heat during APU and / or FCS operating to avoid overheating.

[0022] Conversion of thermal heat power to electrical power.

[0023] Thermal -electrical power conversion.

[0024] Use of thermal waste heat of APU and / or FCS to avoid overheating.

[0025] SUMMARY AS WELL AS TECHNICAL SOLUTIONS AND ADVANTAGEOUS EFFECTS OF THE INVENTION

[0026] A thermal heat management system according to the present invention is capable of solving the above objectives with the described technical features disclosed within these application documents.

[0027] The thermal heat management system can be used in any kind of static or moving environment or entity as further described below.

[0028] Such an environment or entity will be described as area of use throughout this application.

[0029] The thermal heat management system can be used in any area of use such as vehicles such as transport vehicles such as, for example, aircraft, trains, busses, trucks, ships or cars, more particularly, passenger transport vehicles for passenger transportation such as, for example, passenger aircraft, passenger trains, passenger busses, passenger trucks, passenger ships or passenger cars, even more particularly, respective lavatories, cabins, passenger and / or crew rest compartments, galleys and / or kitchenettes on said passenger transport vehicles such as, for example, a lavatory, a cabin and / or a galley of an aircraft, a lavatory, a cabin, a galley and / or a kitchenette of a train, a lavatory, a cabin, a galley and / or a kitchenette on a bus, a lavatory, a cabin, a galley and / or a kitchenette on a truck, a lavatory, a cabin, a galley and / or a kitchenette on a ship or lavatory, a cabin, a galley and / or a kitchenette of a RV (recreational vehicle).

[0030] The thermal heat management system can also be used in any area of use such as buildings, houses, flats or immobile installations, such as a lavatory, a cabin, a galley and / or a kitchenette thereof.

[0031] Examples for a device or equipment encompass touchless, pushbutton, mechanical, electromechanical faucets and / or lights, soap dispensers or water dispensers in a lavatory or galley compartment, or disinfection dispensers with a location in the aircraft cabin.

[0032] Examples for a device or equipment may further encompass cabin attendant call units, seat inclination mechanisms, gasper switches, and / or opening / locking mechanisms of an overhead stowage compartment. The terms “device” and “equipment” are employed interchangeably, their meaning, however, is understood in the conventional understanding of each word and should not be considered as synonyms.

[0033] This thermal heat management system of the present invention is intended to be capable to be integrated, for example, in the locations mentioned above such as, for example, any cabin area of commercial and / or military aircraft.

[0034] Examples of the equipment and / or devices could be operation of a reading light in the cabin, a seat inclination function, and / or activating a water faucet in the lavatory, but the present invention is not limited thereto and relates to any equipment and / or device within the locations mentioned above.

[0035] The use of CO2 producing equipment and / or devices such as aircraft equipment and / or devices such as an Auxiliary Power Unit (APU) could be replaced by fuel cell systems (FCS), which would be intended to be used inside the vehicle as mentioned above such as, for example, an aircraft, for example, to restart equipment and / or devices such as engines, and generate power for emergency utilities. Electrical power production used, for example, for a passenger cabin, a galley, a lavatory, a cockpit or in other suitable locations within a vehicle such as, for example, an aircraft. During power generation PEM fuel cell systems generate a severe amount of thermal heat. Therefore, thermal heat management in a vehicle cabin and / or cargo is challenging due to the necessity of heat exchange systems.

[0036] The use of Liquid Hydrogen (LH2) for vehicle propulsion will be installed to reduce CO2 emission during (flight) operation. Due to expensive LH2 production and complicated storage in vehicles such as an aircraft, for example, the use of LH2 is expected to focus on propulsion up to 98% of the fuel capacity. The use of secondary power generation using LH2 for vehicles such as aircrafts, for example, and areas such as aircraft cabin management and operation, for example, is expected to be less than 2% of the fuel capacity.

[0037] Fuel Cell system, for example PEM FCS, powered by LH2 for secondary power generation are expected to be installed at the rear aircraft partition, such as an APU section, to supply cabin management systems and utilities. During operation of a FCS such as, for example, a PEM FCS, the gross power produced is split in 50% electrical power, variable VDC, and 50% thermal heat power leading to a temperature of about 80° to 90°C. The rated power is expected to be between about 2 x 50 kW and / or 2 x 75 kW. Due to limited electrical power for cabin interiors of up to 150 kW the cabin ventilation may adsorb 130 kW and the cabin management and utilities may adsorb 20 kW.

[0038] According to these limitations the active use of thermal heat power at a secondary FCS heat exchanger is highly recommended. The thermal heat could, for example, be used for pre-heating the water systems, such as fresh water and / or waste water systems (FW and WW), as well as for the utilities such as lavatories and / or galleys. Further on, to increase the electrical power generation for cabin interiors, a thermal heat exchange system (THES) is proposed in order to convert the thermal heat power into electrical power.

[0039] Further, using Peltier elements based on the Seebeck effect on the surface on heat exchangers, mounted on the APU doors, for example, of the rear aircraft part use the temperature difference between the ambient aircraft flow temperature (about -55°C) and the heat exchanger inlet temperature (about +85°C) to convert a difference of about 140 K to electrical power by silicon- based Peltier elements, for example.

[0040] A THES could be realized by an Organic Rankine Process (ORC), such as an inverse chiller system. Athermal heat exchange system (THES) for an aircraft secondary PEM fuel cell system has a compartment for generating electrical power used suppling cabin interior systems. For the THES installed at the APU compartment, the thermal heat flux of the secondary FCS heat exchanger heats up the circulating fluid of the ORC process in the evaporator. The fluid vapor drives a turbine-generator power train to generate electrical power to the THES itself and the cabin interiors consumers, such as equipment and / or devices.

[0041] By implementing this invention, the following aspects can be improved:

[0042] Reduction of conventional thermal heat exchanger in vehicle operation such as aircraft operation.

[0043] Use of Fuel Cell System thermal heat power for vehicle cabin operation such as aircraft cabin operation for reduction of electrical power

[0044] Water pre-heating possibility in Lavatories.

[0045] Pre-heating of vehicle inserts such as galley inserts such as ovens, water boilers, coffee maker, etc.

[0046] Thermo-electric power production by conversion of temperature difference of FCS secondary cooler and vehicle fuselage skin such as aircraft fuselage skin for example by Peltier elements and / or Seebeck generators.

[0047] Thermal heat power generators for electrical power generation for vehicle consumers such as cabin consumers such as, for example, ventilation. DESCRIPTION OF THE DRAWINGS

[0048] Fig i shows an exemplary thermal heat management system according to the present invention.

[0049] Fig. 2 shows an exemplary thermal heat management system according to the present invention.

[0050] Figs. 3-4 show exemplary thermoelectric components and modules custom-tailored geometries according to the present invention.

[0051] Fig. 5 shows an exemplary use of a PEM fuel cell system (FCS) application for use in an aircraft with material and power flows according to the present invention.

[0052] Fig. 6-7 show views of the physical configuration and working principle of a Peltier element based on the Seebeck effect, according to the present invention.

[0053] Fig. 8 shows an exemplary perimeter FCS system with a secondary cooling circuit which allows to connect to the potable water system and to adapt an OCR system and Peltier elements to the Radiator of the secondary circuit.

[0054] Fig. 9 shows an exemplary perimeter FCS system with a Water / Water heat exchanger connected to the airplane electronics cooling loop and an Air / Water heat exchanger for hot potable water conditioning.

[0055] DETAILED DESCRIPTION OF THE DRAWINGS

[0056] The use of CO2 producing equipment and / or devices such as aircraft equipment and / or devices such as an Auxiliary Power Unit (APU) could be replaced by fuel cell systems (FCS), which would be intended to be used inside the vehicle as mentioned above such as, for example, an aircraft, for example, to restart equipment and / or devices such as engines, and generate power for emergency utilities. Electrical power production used, for example, for a passenger cabin, a galley, a lavatory, a cockpit or in other suitable locations within a vehicle such as, for example, an aircraft. During power generation PEM fuel cell systems generate a severe amount of thermal heat. Therefore, thermal heat management in a vehicle cabin and / or cargo is challenging due to the necessity of heat exchange systems.

[0057] The use of Liquid Hydrogen (LH2) for vehicle propulsion will be installed to reduce CO2 emission during (flight) operation. Due to expensive LH2 production and complicated storage in vehicles such as an aircraft, for example, the use of LH2 is expected to focus on propulsion up to 98% of the fuel capacity. The use of secondary power generation using LH2 for vehicles such as aircrafts, for example, and areas such as aircraft cabin management and operation, for example, is expected to be less than 2% of the fuel capacity.

[0058] Fuel Cell system, for example PEM FCS, powered by LH2 for secondary power generation are expected to be installed at the rear aircraft partition, such as an APU section, to supply cabin management systems and utilities. During operation of a FCS such as, for example, a PEM FCS, the gross power produced is split in 50% electrical power, variable VDC, and 50% thermal heat power leading to a temperature of about 80° to 90°C. The rated power is expected to be between about 2 x 50 kW and / or 2 x 75 kW. Due to limited electrical power for cabin interiors of up to 150 kW the cabin ventilation may adsorb 130 kW and the cabin management and utilities may adsorb 20 kW.

[0059] According to these limitations the active use of thermal heat power at a secondary FCS heat exchanger is highly recommended. The thermal heat could, for example, be used for pre-heating the water systems, such as fresh water and / or waste water systems (FW and WW), as well as for the utilities such as lavatories and / or galleys. Further on, to increase the electrical power generation for cabin interiors, a thermal heat exchange system (TELES) is proposed in order to convert the thermal heat power into electrical power.

[0060] Further, using Peltier elements based on the Seebeck effect on the surface on heat exchangers, mounted on the APU doors, for example, of the rear aircraft part use the temperature difference between the ambient aircraft flow temperature (about -55°C) and the heat exchanger inlet temperature (about +85°C) to convert a difference of about 140 K to electrical power by silicon- based Peltier elements, for example.

[0061] A TELES could be realized by an Organic Rankine Process (ORC), such as an inverse chiller system. Athermal heat exchange system (TELES) for an aircraft secondary PEM fuel cell system has a compartment for generating electrical power used for supplying cabin interior systems. For the TELES installed at the APU compartment, the thermal heat flux of the secondary FCS heat exchanger heats up the circulating fluid of the ORC process in the evaporator. The fluid vapor drives a turbine-generator power train to generate electrical power to the THES itself and the cabin interiors consumers, such as equipment and / or devices. It is proposed to apply an ORC process for example by using an inverse aircraft Galley chiller system to absorb the thermal heat of the FCS secondary heat exchanger (80 - 100 kW at 80 - 90°C) in an ORC process to produce electrical power. This Thermal Heat Exchange System (THES) could operate in line with a FCS process producing linear increasing electrical and thermal heat power, for example, from 5 to 100 kW rated power. The thermal heat power of about 50% is used for the THES system drivers and cabin interior systems.

[0062] It is proposed to apply a lightweight and thin film thermo-electrical generator to absorb and change temperature difference between the aircraft surface temperature (-55 °C) and the FCS heat exchanger surface (+85 °C) into electrical power by use of so-called Peltier Elements (Seebeck generators). The FCS heat exchangers need continuous heat energy flow into a heat sink in order to cool down the FCS system at design and operation temperature of +80 °C. Large surfaces in cabin and / or cargo sections could be used to provide constant outside temperatures between (+30 to - 55 °C). Surface temperatures at FCS secondary cooling device are between (+30 - + 90 °C), so that the temperature differences are between 0 to 140 °C. Seebeck generators designed as electronic chip design produce electrical power from temperature differences. Due to the large surfaces and temperature differences thermo-electrical generators could be used at aircraft cabin and / or cargo to reduce overheating. Dissipating thermal heat power resulting from the converting process could be released in cargo space.

[0063] By implementing this invention, the following aspects can be improved:

[0064] Reduction of conventional thermal heat exchanger in vehicle operation such as aircraft operation.

[0065] Use of Fuel Cell System thermal heat power for vehicle cabin operation such as aircraft cabin operation for reduction of electrical power

[0066] Water pre-heating possibility in Lavatories.

[0067] Pre-heating of vehicle inserts such as galley inserts such as ovens, water boilers, coffee maker, etc.

[0068] Thermo-electric power production by conversion of temperature difference of FCS secondary cooler and vehicle fuselage skin such as aircraft fuselage skin for example by Peltier Elements and / or Seebeck generators.

[0069] Thermal heat power generators for electrical power generation (ORC) for vehicle consumers such as cabin consumers such as, for example, ventilation. Fig i shows an exemplary thermal heat management system according to the present invention. The left block diagram shows the ORC- process as a closed loop process. The thermal heat e.g. derived from the fuel cell 6 heats up the pressurized organic cooling fluid leading to a phase change from liquid to gaseous conditions. The gaseous organic cooling fluid expands within a turbine 12, thus providing power to the electrical power generator 13. The converted electrical power will be sent into the aircraft electrical system. Further on the expanded organic cooling fluid passes a condenserl4, where it changes from the gaseous into the liquid phase. In the last step the cooled down fluidic cooling fluid will be pressurized within the pump 15 and sent to the evaporator 15 where the new cycle starts.

[0070] The right block diagram shows this ORC- process in more detail with attached liquid reservoir and electric generator 13.

[0071] Fig. 2 shows an exemplary thermal heat management system 1 according to the present invention. This block diagram shows a combination of an ORC -process and Peltier elements 6 within the area where the actual APU is located within the tail of an aircraft 20. The picture on the right side shows this aircraft tail area with opened access doors. The hot heat exchanger of the ORC process provides the condensation of the organic cooling fluid . The Peltier elements 7 are in direct contact with the hot heat exchanger surface on one side and open to the internal space with aircraft internal temperature. This high temperature differential is used by the Peltier Elements 7 to generate the electrical power.

[0072] The heat exchanger 1 will be supplied via the air intake with cold ambient air, which leaves the heat exchanger, e.g. via the APU exhaust. On ground this cooling air flow may be generated by a fan. During flight the aerodynamic suction will drive the cooling air flow. It is also anticipated to utilize the cold temperature of the APU service door to transfer a portion of the heat into the outer ambient of the aircraft.

[0073] Figs. 3 shows a side view of an exemplary thermoelectric component with custom-tailored geometries according to the present invention. The flat surface is mainly used to transport the thermal flows. The different metallic materials are joined together in material contact at the flat surfaces on either side.

[0074] Figs. 4 shows a top view of an exemplary thermoelectric component with custom-tailored geometries according to the present invention. The flat surface is mainly used to transport the thermal flows. Fig- 5 shows an exemplary use of a PEM fuel cell system (FCS) application for use in an aircraft with material and power flows according to the present invention. The fuel cell system 6 is provided with hydrogen and oxygen via oxygen storage or ambient air and produces hot water and electricity. The regeneration of the heat energy provides additional electricity, warm water, and heat for the galley or other cabin systems and oxygen depleted air for inerting purpose of the aircraft system as shown in the diagram.

[0075] Figs. 6 - 7 show views of the physical configuration and working principle of a Peltier element 6 based on the Seebeck effect, according to the present invention. Dissimilar metals are connected together, at the junction points. If one junction point is heated and the counter junction point is cooled down, leading to a temperature differential, an electrical potential is generated between the two points creating the Seebeck voltage. As soon as both points are connected via an electrical circuit an electrical current is generated.

[0076] Fig. 8 shows an exemplary perimeter FCS system with a secondary cooling circuit which allows to connect to the potable water system and to adapt an OCR system and Peltier elements to the radiator of the secondary circuit. The secondary circuit is connected to the primary circuit via a heat exchanger unit.

[0077] Fig- 9 shows an exemplary perimeter FCS system with a Water / Water heat exchanger connected to the airplane electronics cooling loop and an Air / Water heat exchanger for hot potable water conditioning as a further example for heat transfer to other aircraft systems.

[0078] ALTERNATIVE EMBODIMENTS

[0079] This invention describes a solution for a thermal heat management system in an aircraft, but similar areas of use as stated above could be used for various equipment and / or for various devices.

[0080] INDUSTRIAL APPLICABILITY

[0081] This invention can be applied, for example, in vehicles such as, for example, commercial and / or military aircraft.

[0082] The present invention can be used in any areas of commercial or military aircraft where equipment and / or devices can be activated by passengers and / or crew members.

[0083] LIST OF ABBREVIATIONS

[0084] APU auxiliary power unit

[0085] FCS fuel cell system

[0086] PEM polymer electrolyte membrane

[0087] FW fresh water

[0088] WW waste water

[0089] THES thermal heat exchange system

[0090] ORC organic rankine system

[0091] LIST OF REFERENCE NUMERALS

[0092] 1 thermal heat management system

[0093] 2 auxiliary power unit APU

[0094] 3 thermal heat exchange system THES

[0095] 4 water system

[0096] 5 aircraft

[0097] 6 fuel cell system FCS

[0098] 7 Peltier element

[0099] 12 turbine

[0100] 13 electrical power generator

[0101] 14 condenser

[0102] 15 pump

[0103] 20 aircraft

Claims

CLAIMS1. A thermal heat management system (1) comprising: at least one auxiliary power unit (2), and at least one thermal heat exchange system (3) connected to the at least one auxiliary power unit (2), wherein the at least one thermal heat management system (1) is configured to absorb and use thermal heat from the at least one auxiliary power unit (2), wherein the at least one thermal heat management system (1) is configured to transfer a portion of the thermal heat into electrical power.

2. The thermal heat management system (1) according to claim 1, configured to use the absorbed thermal heat to heat at least one water system (4), such as fresh water and / or waste water systems, for example in lavatories and / or galleys and / or galley inserts such as ovens, water boilers and / or coffee makers.

3. The thermal heat management system (1) according to claim 1 or 2, configured to use the absorbed thermal heat to produce electrical power.

4. The thermal heat management system (1) according to any of the preceding claims, wherein the thermal heat management system is configured to be used in an aircraft (5).

5. The thermal heat management system (1) according to any of the preceding claims, wherein the at least one auxiliary power unit (2) comprises at least one fuel cell system (6) .

6. The thermal heat management system (1) according to claim 5, wherein the at least one fuel cell system (6) comprises at least one polymer electrolyte membrane fuel cell system.

7. The thermal heat management system (1) according to any of the preceding claims, wherein the thermal heat management system (1) is scalable to produce power from 0 kW to 50 kW.

8. The thermal heat management system (1) according to any of the preceding claims, wherein the thermal heat exchange system (1) is realized by an organic Rankine process.

9. The thermal heat management system according to claim 8, wherein the organic Rankine process uses an inverse chiller system.

10. The thermal heat management system (1) according to any of the preceding claims, wherein the thermal heat management system comprises a secondary fuel cell system heat exchanger.

11. The thermal heat management system (1) according to any of the preceding claims, wherein the at least one thermal heat management system (1) comprises a thin film thermoelectrical generator.

12. The thermal heat management system (1) according to any of the preceding claims, wherein the at least one thermal heat exchange system (1) comprises at least one Peltier element(7) for producing thermo-electric power by conversion of a temperature difference.

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