Exhaust airflow system
An airflow exhaust system for delivering exhaust produced from a fuel cell to optimize aircraft performance. Exhaust is distributed using a conduit network and released through outlets on the aircraft skin to provide boundary layer control for the aircraft. A control system distributes exhaust for boundary layer control, actuator control, and propulsion.
1 . An aircraft comprising:
a fuel cell configured to consume hydrogen and produce an exhaust;
one or more actuator control outlets disposed on the aircraft;
one or more boundary layer control outlets disposed on the aircraft;
a conduit configured to direct at least some of the exhaust from the fuel cell directly to the one or more actuator control outlets and the one or more boundary layer control outlets, wherein the one or more actuator control outlets are disposed immediately forward of a control surface and configured to direct the exhaust upwards relative to the control surface for increasing lift generated by the control surface, and the boundary layer control outlets are configured to release the exhaust to optimize an aircraft boundary layer and reduce skin friction drag; and
a control system configured to distribute a first portion of the exhaust to the boundary layer control outlets and a second portion of the exhaust to the actuator control outlets, wherein distribution of the first portion of exhaust causes a reduction of skin friction drag and distribution of the second portion of exhaust causes an increase in aircraft lift.
2 . The aircraft of claim 1 , wherein the control system is configured to determine a flight condition, wherein the control system is communicatively connected to the actuator control outlets and the boundary layer control outlets, and configured to change a degree of openness in a plurality of valves and distribute exhaust to the actuator control outlets to increase aircraft lift and the boundary layer control outlets to reduce skin friction drag based on the flight condition.
3 . The aircraft of claim 2 , wherein when the control system determines the flight condition creates a need for an increase in propulsion, and the control system changes the degree of openness of a first valve of the plurality of valves to increase an amount of exhaust devoted to a propulsion outlet disposed on an aircraft skin area configured to expel the exhaust and increase a propulsion characteristic of the aircraft.
4 . The aircraft of claim 2 , wherein when the control system determines that the aircraft is at a cruise state of flight, the control system changes the degree of openness of a second valve of the plurality of valves to distribute the exhaust to the boundary layer control outlets to reduce skin friction drag of the aircraft.
5 . The aircraft of claim 2 , wherein when a detection is made by the control system that the aircraft requires deflection of the control surface, the control system causes a third valve of the plurality of valves to increase an amount of exhaust transmitted to the actuator control outlets increasing lift produced by the control surface immediately behind the actuator control outlets.
6 . The aircraft of claim 2 , wherein the control system is configured to cause a fourth valve of the plurality of valves to release air directly to an atmosphere control outlet disposed on an aircraft skin and configured to release the exhaust to an exterior of the aircraft wherein the atmosphere control outlet does not affect an aerodynamic property of the aircraft.
7 . The aircraft of claim 1 , wherein the boundary layer control outlets are disposed on a portion of an aircraft fuselage, wherein the one or more boundary layer control outlets are configured to release the exhaust to energize turbulent flow and prevent separation of air layers.
8 . The aircraft of claim 1 , wherein the actuator control outlet is disposed immediately forward of an elevator.
9 . The aircraft of claim 1 , comprising a control surface having an angle of deflection which corresponds to a degree of aircraft lift and release of the exhaust changes the degree of aircraft lift, which corresponds to the angle of deflection of the control surface.
10 . A system comprising:
a fuel cell configured to consume hydrogen and produce an exhaust;
a boundary layer control outlet disposed on an aircraft skin and an actuator control outlet disposed on a wing;
a conduit configured to deliver the exhaust to at least the boundary layer control outlet and the actuator control outlet;
the actuator control outlet being disposed immediately in front of a an elevator having an angle of deflection which corresponds to a degree of aircraft lift, and wherein release of exhaust from the actuator control outlet increases the degree of aircraft lift, which corresponds to the angle of deflection of the elevator; and
a controller configured to determine a flight condition and distribute the exhaust based on the flight condition, wherein the exhaust is distributed through the conduit to the boundary layer control outlet and the actuator control outlet to optimize an aircraft boundary layer and reduce skin friction drag.
11 . The system of claim 10 , comprising a propulsion outlet configured to direct the exhaust to increase propulsion of the aircraft.
12 . The system of claim 11 , wherein the controller is configured to meter exhaust flow between at least two of the boundary layer control outlet, the actuator control outlet, and the propulsion outlet, to optimize efficiency of the aircraft.
13 . The system of claim 10 , wherein the boundary layer control outlet is disposed onto a fuselage of an aircraft.
14 . The system of claim 10 , wherein the actuator control outlet is disposed immediately forward of an aileron.
15 . The system of claim 10 , wherein the conduit delivers the exhaust from the fuel cell directly to at least the boundary layer control outlet or the actuator control outlet.
16 . The system of claim 10 , wherein the exhaust does not pass through a heat exchanger prior to being released from the actuator control outlet.
17 . The system of claim 10 , wherein the actuator control outlet is disposed immediately forward of a rudder.
18 . An aerodynamic process for use in an aircraft equipped with a fuel-cell power system, the process comprising:
receiving an exhaust from the fuel-cell power system;
determining a flight condition based on aircraft diagnostic information;
releasing a first portion of the exhaust from the fuel-cell power system from an actuator outlet disposed on an aircraft wing immediately in front of an elevator when the flight condition indicates a deflection of the elevator, wherein the release of the first portion of exhaust increases a lift characteristic of the elevator;
releasing a second portion of the exhaust from the fuel-cell power system from a boundary layer control outlet disposed on an aircraft fuselage when the flight condition indicates the aircraft is in a cruise state of flight, wherein the release of the second portion of exhaust reduces skin friction drag of the aircraft; and
releasing a third portion of the exhaust from the fuel-cell power system from a propulsion outlet disposed on an aircraft body when the flight condition indicates an increase in thrust, wherein the release of the third portion of the exhaust increases propulsive power of the aircraft.
19 . The process of claim 18 , wherein release of the first portion of exhaust increases a degree of aircraft lift which corresponds to an angle of deflection of the elevator.
20 . The process of claim 18 , comprising determining an amount of the first portion of exhaust, the second portion of exhaust, and the third portion of exhaust, and metering the first, second, and third portions to the actuator outlet, the boundary layer outlet, and the propulsion outlet, respectively.