Turbofan thermoelectric generation
A gas turbine engine has: a core flowpath sequentially through one or more fan sections, one or more compressor sections, a combustor section, and one or more turbine sections; a bypass flowpath extending through the one or more fan sections and bypassing the combustion section; a heat exchanger in the bypass flowpath placing a portion of the bypass flowpath in heat exchange relation with a second fluid flowpath; a first thermoelectric generator having a first side upstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath; and a second thermoelectric generator having a first side downstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath.
1 . A gas turbine engine comprising:
a core flowpath sequentially through one or more fan sections, one or more compressor sections, a combustor section, and one or more turbine sections;
a bypass flowpath extending through the one or more fan sections and bypassing the combuster section;
a heat exchanger in the bypass flowpath placing a portion of the bypass flowpath in heat exchange relation with a second fluid flowpath;
at least one first thermoelectric device having a first side upstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath; and
at least one second thermoelectric device having a first side downstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath.
2 . The gas turbine engine of claim 1 wherein:
the second fluid flowpath is a compressor bleed.
3 . The gas turbine engine of claim 1 wherein:
the second fluid flowpath comprises one or more of:
a fuel flowpath fuel;
a lubricant flowpath; and
a glycol-based coolant flowpath.
4 . The gas turbine engine of claim 1 wherein:
the at least one first thermoelectric device is a plurality of first thermoelectric devices connected to form a first thermoelectric generator (TEG);
the at least one second thermoelectric device is a plurality of second thermoelectric devices connected to form a second thermoelectric generator (TEG);
the first thermoelectric generator and the second thermoelectric generator each have a first side and a second side; and
the gas turbine engine is in an aircraft nacelle and the first thermoelectric generator and second thermoelectric generator second sides are exposed to an external airflow along an outside of the nacelle.
5 . The gas turbine engine of claim 4 wherein:
the first thermoelectric generator comprises said first thermoelectric devices in a circumferential and streamwise array; and
the second thermoelectric generator comprises said second thermoelectric devices in a circumferential and streamwise array.
6 . An aircraft including the gas turbine engine of claim 1 and further comprising:
a storage battery.
7 . The aircraft of claim 6 wherein:
the at least one first thermoelectric device and the at least one second thermoelectric device are coupled to the battery to allow charging of the battery.
8 . The aircraft of claim 7 wherein:
the at least one first thermoelectric device and the at least one second thermoelectric device are coupled to the battery to allow powering by the battery.
9 . A method for operating the aircraft of claim 6 , the method comprising:
in a first mode, the at least one first thermoelectric device generating electricity and the at least one second thermoelectric device generating electricity; and
in a second mode, the at least one first thermoelectric device actively cooling the bypass flow and the at least one second thermoelectric device generating electricity.
10 . The method of claim 9 further comprising:
using one or more thermoelectric devices of the at least one first thermoelectric device and/or the at least one second thermoelectric device to measure temperature; and
responsive to the temperature measurement, controlling flow along the second fluid flowpath.
11 . The method of claim 9 wherein:
the gas turbine engine is a first gas turbine engine and the aircraft has a second gas turbine engine;
the second gas turbine engine also has:
a core flowpath sequentially through one or more fan sections, one or more compressor sections, a combustor section, and one or more turbine sections;
a bypass flowpath extending through the one or more fan sections and bypassing the combustor section;
a heat exchanger in the bypass flowpath placing a portion of the bypass flowpath in heat exchange relation with a second fluid flowpath;
at least one first thermoelectric device having a first side upstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath; and
at least one second thermoelectric device having a first side downstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath;
with the first gas turbine engine in its first mode, the second gas turbine engine at least one first thermoelectric device generating electricity and the second gas turbine engine at least one second thermoelectric device generating electricity; and
with the first gas turbine engine in its second mode, the second gas turbine engine at least one first thermoelectric device generating electricity and the second gas turbine engine at least one second thermoelectric device generating electricity.
12 . The method of claim 11 wherein:
the first gas turbine engine is in its first mode and the second gas turbine engine at least one first thermoelectric device generating electricity and the second gas turbine engine at least one second thermoelectric device generating electricity during a cruise phase; and
the first gas turbine engine is in its second mode and the second gas turbine engine at least one first thermoelectric device generating electricity and the second gas turbine engine at least one second thermoelectric device generating electricity during a takeoff.
13 . The method of claim 11 wherein:
with the first gas turbine engine in its second mode and the second gas turbine engine at least one first thermoelectric device generating electricity and the second gas turbine engine at least one second thermoelectric device generating electricity a bleed flow rate from the first gas turbine engine is greater than a bleed flow rate from the second gas turbine engine.
14 . The method of claim 13 further comprising with the first gas turbine engine:
using one or more of the at least first thermoelectric device and/or the at least one second thermoelectric device to measure temperature; and
responsive to the temperature measurement, controlling flow along the second fluid flowpath.
15 . A method for using the gas turbine engine of claim 1 comprising:
using one or more of the at least first thermoelectric device and/or the at least one second thermoelectric device to measure temperature; and
responsive to the temperature measurement, controlling flow along the second fluid flowpath.
16 . A gas turbine engine comprising:
a core flowpath sequentially through one or more fan sections, one or more compressor sections, a combustor section, and one or more turbine sections;
a bypass flowpath extending through the one or more fan sections and bypassing the combustor section;
a heat exchanger in the bypass flowpath placing a portion of the bypass flowpath in heat exchange relation with a second fluid flowpath;
a first thermoelectric generator having a first side upstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath; and
a second thermoelectric generator having a first side downstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath.
17 . A method for operating a gas turbine engine, the gas turbine engine comprising:
a core flowpath sequentially through one or more fan sections, one or more compressor sections, a combustor section, and one or more turbine sections;
a bypass flowpath extending through the one or more fan sections and bypassing the combustor section;
a heat exchanger in the bypass flowpath placing a portion of the bypass flowpath in heat exchange relation with a second fluid flowpath;
a first thermoelectric generator having a first side upstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath; and
a second thermoelectric generator having a first side downstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath,
the method comprising:
in a first mode, thermoelectrically generating electricity upstream of the heat exchanger while thermoelectrically generating electricity downstream of the heat exchanger along the bypass flowpath; and
in a second mode, thermoelectrically heating the bypass flow upstream of the heat exchanger while thermoelectrically generating electricity downstream of the heat exchanger along the bypass flowpath.
18 . The method of claim 17 further comprising:
in a third mode, thermoelectrically cooling the bypass flow downstream of the heat exchanger along the bypass flowpath.
19 . The method of claim 17 further comprising:
in a third mode, thermoelectrically cooling the bypass flow upstream of the heat exchanger while thermoelectrically cooling the bypass flow downstream of the heat exchanger along the bypass flowpath.