Have you ever wondered how short the time you could travel around the world if you could fly at supersonic speeds?Or have you ever wondered why airplanes make loud ** noises when flying?
The answers to these questions are all related to a mysterious quantifier, and that is Mach. Today, let's explore the mysteries of Mach and see what it has to do with our lives.
In the field of aircraft, we often hear a mysterious word -"Mach"。This word stands for a unit of measurement of flight speed and is often used to describe the speed of aircraft, rockets, etc.
To better understand the origin of the term, we need to recall a prominent Austrian scholar, Ernst Mach (1838-1916). He was not only a physicist, but also a psychologist and philosopher, who made great contributions to the field of fluid mechanics and supersonic flight.
Now, let's dive in"Mach"The specific meaning of the word. The Mach number, in simple terms, is the ratio of speed to the speed of sound. However, the speed of sound, which is the speed at which sound travels, varies under conditions such as altitude, temperature, and atmospheric density.
Therefore, the Mach number is not a fixed velocity value, but a relative concept. For example, when we say ma16 o'clock, which means that the flight speed is 1 of the local speed of sound6 times.
Let's travel back in time to 1887, when Maher and his collaborator Pete Setcher used the Schlieren technique to photograph some supersonic flights. With these, they discovered the shock wave generated by the object when flying at supersonic speeds and an interesting phenomenon - the Mach cone.
In addition, they derived an important formula, known as the Mach angle, which describes the angle between the cone of the shock wave and the direction of motion of the object and the Mach number. These discoveries had a profound impact on the development of aerodynamics and supersonic flight.
In order to commemorate Mach's outstanding contributions, people call the ratio of velocity to the speed of sound the Mach number, the cone of the shock wave is called the Mach cone, and the angle between the cone of the shock wave and the direction of motion of the object is called the Mach angle.
These concepts not only have a profound impact in the field of science, but also give us a deeper understanding of the mysteries of flight.
In the last century, mankind's yearning for the speed of sound has been very strong. As the speed of aircraft continued to increase, there was a strong interest in the possibility of breaking through the speed of sound. However, it is not easy to surpass the speed of sound.
When approaching the speed of sound, the aircraft will encounter a series of difficulties and dangers, such as a sharp increase in air resistance, deformation of the aircraft structure, failure of control, and the generation of shock waves. Therefore, to achieve supersonic flight, it is necessary to have special designs and technologies.
The first attempt to surpass the speed of sound was Germany. During World War II, they developed a rocket called the V-2, which could reach a speed of 5,000 kilometers per hour, well above the speed of sound.
However, this rocket is not designed to explore the speed of sound, but rather as an attack on enemy cities. In addition, it is neither manned nor **, so it cannot be counted as a supersonic vehicle in the true sense of the word.
The milestone of supersonic flight occurred on October 14, 1947, when a pilot named Charles Yeager successfully broke through the speed of sound in the Mojave Desert in California, USA, piloting a rocket plane known as the Bell X-1. This momentous moment is regarded as the first time in human history that supersonic flight has been achieved, marking a new era in aviation technology.
The Bell X-1 is not an ordinary aircraft, it is specifically designed to study supersonic flight. The aircraft features an all-new rocket engine, a streamlined fuselage, and adjustable wings and tails, allowing it to adapt to different flight situations.
Jaeger piloted the plane, in 1At an altitude of 10,000 meters, it is 1The speed of Mach 07 successfully broke through the sound barrier and realized the long-held dream of mankind. This breakthrough marks the rapid development of science and technology, opening up a completely new path for the future of aviation technology and hypersound.
After Jaeger ushered in a new era of supersound, many warriors continued to push the limits of sound, flying a variety of supersonic planes and creating jaw-dropping feats in the skies.
Back on August 26, 1953, American pilot Joseph Keating flew the D-558-2 rocket plane at sea level at 2Flying at Mach 44, becoming the first person to surpass twice the speed of sound at sea level.
Subsequently, on December 12, 1956, American pilot Milton Thompson flew an X-2 rocket plane at a high altitude at 3Flying at Mach 2, becoming the first person to surpass three times the speed of sound.
Then, on May 5, 1961, American astronaut Alan Shepard piloted the Mercury-Redstone rocket plane to break through the atmosphere at 7Speed of Mach 8 became the first person to go into space.
Then, on October 3, 1966, American pilot William Knight flew an X-15 rocket plane at 6 per second at high altitudeFlying at a speed of Mach 7, it set a speed record for a manned aircraft.
Now that you know about the speed of sound, are you also curious about how many Mach can humans reach now?
The fastest speed record holder in man is not a pilot, but a special probe called Helios 2. The probe was launched by the National Aeronautics and Space Administration (NASA) in 2018 and its mission is to explore the surface and atmosphere of the sun in depth.
Due to its proximity to the Sun and the influence of the Sun's strong gravitational pull, Helios 2 gradually increased its speed, eventually reaching a staggering 252,792 kilometers per hour, equivalent to 70 kilometers per second22 km, or 0000234 the speed of light. That's an incredible speed, equivalent to Mach 205!
This magnificent achievement is not only the record for the largest speed ever set by man, but also far exceeds the speed of sound. The speed of Helios 2 gives us a deeper understanding of the concept of the power and speed of the movement of celestial bodies in the solar system.
Yes, there are human vehicles capable of reaching supersonic speeds. Currently, one of the fastest fighters in the world is the American F-15 Hawk, which is capable of reaching 2The maximum speed of Mach 5 is equivalent to 3000 km/h.
In 1985, the fighter set an astonishing world record: it took only three and a half minutes to reach an altitude of 30,000 meters from the ground, which is equivalent to a gain of 140 meters per second.
Humanity's quest for speed extends beyond the skies to the underwater and underground. Under water, the speed is usually much lower than in the air due to the resistance and pressure limitations of the water. At present, the fastest underwater vehicle designed by man is the super intercontinental missile developed by Russia.
This missile is capable of driving at 0.0 per second under waterFlying at a speed of Mach 8, it is equivalent to 1000 kilometers per hour. Such missiles are capable of carrying nuclear warheads and pose a significant threat to the enemy.
As for the underground, the speed is limited by soil resistance and temperature, and is usually lower than the underwater speed. Currently, the fastest underground vehicle studied by humans is a vehicle known as a supersonic tunnel.
Countries such as the United States and China are working on such tunnels, which can be underground at 0It runs at Mach 3, which is equivalent to 400 kilometers per hour.
This type of tunnel utilizes vacuum and magnetic levitation technology to reduce air resistance and friction, thereby improving transportation efficiency. The development of this technology is expected to change the way underground transportation is done in the future, providing a more efficient and fast underground transportation system.
Human beings' pursuit of sound is not only for the stimulation of speed, but also to explore unknown areas and realize human dreams.
The technology of supersonic flight has brought great development to the aviation and aerospace industry of mankind, and has also provided more possibilities for human transportation and communication.
Today, we can fly across the ocean in a few hours on a supersonic airliner, we can communicate with people around the world through satellites** and the Internet, and we can explore the solar system and the universe with rockets and spacecraft, all of which are the gifts that the technology of supersonic flight has given us.