Patent Application
20220274697
The advent of Concorde and Tu-144 started a new era for commercial airlines, they were thought to be a milestone of pursuing higher speed aircrafts in the commercial aviation history. Although they created world records for commercial airplanes, their tremendous noise during the flight remains as a major problem. Therefore the FAA (federal aviation administration) made a regulation prohibiting supersonic flight over land, which restrict its usage in domestic aviation for most continental countries. Since then many efforts have been made to solve the noise problem, but it still remains as a challenge for aircraft design.
This invention is focus on how to make a quieter supersonic flight. Several techniques and methods have been crafted to solve the noise problem of the sonic boom. Although each of these methods could mitigate the sonic boom, combination of these methods could also be used to archive maximum performance. Part of this invention is based on a little different mechanical explanation of sonic boom in contrast to the classic and gained some inspiration from the aerodynamic advantage of the bird flock's flight. Sonic boom is propagated from aircraft to the ground, so add interference media between them to block the noise wave could reduce the sonic boom level. Using special designed wings could also reduce noise wave. Part of the special wings design is inspired from the bird flock's flight. Using active shock wave to blow away the air at the windward front of the aircraft or using holes at the fuselage bottom to flow away the air underneath the fuselage could reduce the noise wave propagated to travel to the ground.
When an aircraft configured with flat bottom of the fuselage and fly at almost zero angle of attack, it should produce less sonic boom noise, meanwhile it need special designed wings. Although most aircrafts have lift generated from thrust to balance gravity during flight, there still be bumps on the air underneath the fuselage and wings, this might be another source of noise wave. So add holes at the bottom of the fuselage of the traditional aircraft to guide the underneath air to flow away should further reduce such “bumps” could mitigate the sonic boom signature.
According to one embodiment disclosed herein, a method for interfering with an aircraft component expansion wave is provided. The method includes spreading air flow from a nozzle which connected to the fuselage to interfere with the aircraft expansion wave.
According to another embodiment disclosed herein, an apparatus to mitigate the sonic boom is provided. The apparatus includes an air flow source, a pipe, and a nozzle at the end of the pipe to spread the air flow to interfere with expansion wave.
According to another embodiment disclosed herein, an aircraft with quieter supersonic flight is provided. The aircraft includes a fuselage and a pipe installed on the fuselage, an air flow source, and a nozzle connected by the pipe to spread the air flow.
According to another embodiment disclosed herein, a method for interfering with an aircraft component expansion wave is provided. The method includes an interference media where air flow spread from a nozzle connected the aircraft and the aircraft component expansion wave met, the interference media is used for preventing the expansion wave from propagating to the ground.
According to another embodiment disclosed herein, an apparatus to mitigate the sonic boom is provided. The apparatus include an air flow source, a pipe, and a nozzle to spread the air flow and a interference media where the air flow and expansion wave met for interfering.
According to another embodiment disclosed herein, an aircraft with quieter supersonic flight is provided. The aircraft includes a fuselage, a pipe, an air flow source, and a nozzle connected by the pipe to spread air flow, and an interference media where the air flow and the expansion wave met.
According to another embodiment disclosed herein, an aircraft with special designed wings is provided. The aircraft includes a fuselage and multiple rotatable wings installed at the top and/or sides of the fuselage.
According to another embodiment disclosed herein, an aircraft with quieter supersonic flight is provided. The aircraft includes a fuselage with flat bottom, and multiple rotatable wings installed on the top and/or sides of the fuselage.
According to another embodiment disclosed herein, an apparatus to mitigate sonic boom is provided. The apparatus includes a shock wave generator, and a nozzle to spread shock wave in the front of the windward of the aircraft.
According to another embodiment disclosed herein, an aircraft with quieter supersonic flight is provided. The aircraft includes a fuselage, a shock wave generator, and a nozzle to spread shock wave in the front of the windward of the aircraft.
According to another embodiment disclosed herein, an apparatus to mitigate sonic boom is provided. The apparatus includes a fuselage, concave holes at the bottom of the fuselage.
According to another embodiment disclosed herein, an aircraft with quieter supersonic flight is provided. The aircraft includes a fuselage, concave holes at the bottom of the fuselage to to flow away the air underneath during flight.
According to another embodiment disclosed herein, an aircraft with maximum performance of silence for supersonic flight is provided. The aircraft uses a combination of the methods disclosed from this invention.
When an aircraft flying at supersonic or hypersonic speed, there will be a sonic boom generated underneath the flying path. The following detailed description is directed to techniques and methods to mitigate the sonic boom noise.
The sonic boom wave is generated from the aircraft to the ground. So the technique 1 is blocking the wave in middle of it to prevent the noise wave from traveling to the ground. The technique 1 have an active air flow source which could generated from an air flow generator or from the intake of the aircraft, the air flow spread from the nozzle to interfere the aircraft expansion wave to mitigate the sound wave. And it could be extended even further, an interference media is set between the expansion wave the the air flow which could block the sound wave.
The position and length of the interference media must satisfied the following condition in
H>=L2;
L′>=L1+M*H;
where H is the length from the start point of the interference media to the bottom of the aircraft.
L2 is the horizontal distance from start point of the interference media to the front of the aircraft.
L1 is the horizontal distance from start point of the interference media to the rear of the aircraft.
L=L1+L2 equals the length of the aircraft.
M is the mach number of the max aircraft speed.
L′ is the length of the interference media.
The optimal H is H=L2, since it must guarantee the expansion wave generated from the front must be blocked by the interference media. The second equation is guarantee the expansion wave from the rear part of the aircraft also need to be blocked by the interference media.
For example, if M=3.0, L2=0.5*L,
L′>=L1+M*L2=L2+L1+(M−1)*L2
L′>=2*L;
which means, if the aircraft flying at 3 Mach speed, the length of the interference media is at least twice of the length of the aircraft.
Special Designed Wings:
Since the advent of airplane, most aircrafts have wings. But the shape and the structure of the wings haven't changed drastically from the beginning. Although this invention introduced a special designed wings which combined with other technique to mitigate sonic boom noise, it could also be used for other types of aircraft.
The special designed wings also have another advantage. For most traditional commercial aircrafts, when takeoff and landing, the fuselage must head up or down accordingly. While the aircraft with special designed wings could hold the fuselage horizontally during take off and landing, which make the passengers more comfortable. Since using special designed wings, things like stalling will almost never happen at least in theory.
Aircraft configured with the special designed wings could reduce the expansion wave which propagated to the ground, since it comprise special designed wings installed at the top of the fuselage. If the aircraft configured with a fuselage with flat bottom and flying at almost zero angle of attack which could guaranteed by precisely control the angle of each individual smaller wings dynamically during the flight, it should produce less sonic boom noise to the ground.
To solve the sonic boom noise problem, actually it only need reduce the noise level propagated to the ground even it increase noise level propagated to up. So the technique 3 is try to move the noise to go up instead of underneath. By using an high powered shock wave generator, which spread from nozzles to below away the air in front of the aircraft to reduce expansion wave propagated in front and underneath of the aircraft.
Although most aircraft have lift generated from thrust to balance gravity during flight, there still be bumps on the air underneath the fuselage and wings, this might be another source of noise wave. So add holes in the bottom of the fuselage of the traditional aircraft to guide the underneath air to flow away should reduce such “bumps” which could mitigate the sonic boom signature.
As an embodiment disclosed herein, an optimal aircraft by using techniques introduced by this invention for quieter flight is provided.
The optimal aircraft for quieter supersonic flight looks quiet different from traditional aircraft because it put high priority for silence design.
All the smaller wings (Wings 1101, Wings 1102, Wings 1103) are rotatable during flight. There is also a computer system to precisely control the angle of the individual smaller wings to get exactly lift to balance the gravity and keep almost zero angle of attack during flight. Which also make the passengers more comfortable during takeoff and landing.
This conceptional design provide one embodiment, it is obvious easy to get other designs by using combination of the technique described above. All these design should also be considered as portions of this invention.
And all the techniques and methods disclosed herein could also be applied for hypersonic flight or even higher speed flight. All the application to these field by using the techniques and methods described above should also covered by this invention.
The embodiment disclosed herein as described above should not be limited from the true spirit of the principle to solve the noise problem. Since it is obvious easy to use a combination of techniques and methods described above, these should also be covered by this invention.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2019/055577 | 7/1/2019 | WO |
