The use of a jet engine in nature. Report: Reactive motion in nature and technology. Towards an extraordinary discovery

The law of conservation of momentum is of great importance when considering jet propulsion.
Under jet propulsion understand the movement of a body that occurs when some of its part is separated at a certain speed relative to it, for example, when combustion products flow out of a jet nozzle aircraft... In this case, the so-called reactive forcepushing the body.
The peculiarity of the reactive force lies in the fact that it arises as a result of the interaction between the parts of the system itself without any interaction with external bodies.
At the same time, the force imparting acceleration, for example, to a pedestrian, ship or plane, arises only due to the interaction of these bodies with earth, water or air.

So the movement of the body can be obtained as a result of the outflow of a jet of liquid or gas.

In nature, jet propulsion inherent mainly in living organisms living in the aquatic environment.

In technology, jet propulsion is used in river transport (jet engines), in the automotive industry (racing cars), in military affairs, in aviation and astronautics.
All modern high-speed aircraft are equipped with jet engines. they are able to provide the required flight speed.
It is impossible to use engines other than jet engines in outer space, since there is no support there, starting from which one could receive acceleration.

The history of the development of jet technology

The creator of the Russian combat missile was the artillery scientist K.I. Konstantinov. With a weight of 80 kg, the Konstantinov rocket range reached 4 km.

The idea of \u200b\u200busing jet propulsion in an aircraft, the project of a jet aeronautical device, was put forward in 1881 by N.I. Kibalchich.

In 1903, the famous physicist K.E. Tsiolkovsky proved the possibility of flight in interplanetary space and developed a project for the first rocket plane with a liquid-jet engine.

K.E. Tsiolkovsky designed a space rocket train, made up of a series of rockets that work in turn and disappear as fuel is consumed.

Principles of using jet engines

The heart of any jet engine is a combustion chamber, in which, when fuel is burned, gases are formed that have a very high temperature and exert pressure on the walls of the chamber. Gases are ejected from a narrow rocket nozzle at high speed and create jet thrust. In accordance with the law of conservation of momentum, the rocket acquires speed in the opposite direction.

The momentum of the system (rocket-combustion products) remains equal to zero. Since the mass of the rocket decreases, even with a constant velocity of gas outflow, its velocity will increase, gradually reaching its maximum value.
The movement of a rocket is an example of the movement of a body with variable mass. The impulse conservation law is used to calculate its speed.

Jet engines are divided into rocket engines and jet engines.

Rocket engines are on solid or on liquid fuel.
In solid propellant rocket engines, fuel containing both a combustible and an oxidizing agent will be thrown inside the engine's combustion chamber.
IN liquid jet enginesdesigned to run spaceships, fuel and oxidizer are stored separately in special tanks and are pumped into the combustion chamber using pumps. They can use kerosene, gasoline, alcohol, liquid hydrogen, etc. as a fuel, and liquid oxygen, nitric acid, etc., as an oxidizing agent required for combustion.

Modern three-stage space rockets are launched vertically, and after passing through the dense layers of the atmosphere, they are transferred to flight in a given direction. Each rocket stage has its own fuel tank and oxidizer tank, as well as its own jet engine. As fuel burns, spent rocket stages are discarded.

Air-jet engines currently used mainly in aircraft. Their main difference from rocket engines is that oxygen from the air entering the engine from the atmosphere serves as an oxidizer for fuel combustion.
Air-jet engines include turbocompressor engines with both axial and centrifugal compressors.
The air in such engines is sucked in and compressed by a compressor driven gas turbine... The gases escaping from the combustion chamber create a reactive thrust force and rotate the turbine rotor.

At very high flight speeds, the compression of gases in the combustion chamber can be carried out due to the oncoming incoming air flow. There is no need for a compressor.

For most people, the term "jet propulsion" represents modern progress in science and technology, especially in the field of physics. Many people associate jet propulsion in technology with spaceships, satellites and jet aircraft. It turns out that the phenomenon of jet propulsion existed much earlier than the person himself, and independently of him. People only managed to understand, use and develop what is subject to the laws of nature and the universe.

What is jet propulsion?

On english language the word "jet" sounds like "jet". It means the movement of a body, which is formed in the process of separating a part from it at a certain speed. A force is manifested that moves the body in the opposite direction from the direction of movement, separating a part from it. Every time matter is pulled out of the object, and the object moves in the opposite direction, there is a jet motion. In order to lift objects into the air, engineers must design a powerful rocket launcher. By releasing jets of flame, the rocket engines lift it into Earth's orbit. Sometimes rockets launch satellites and space probes.

As for airliners and military aircraft, the principle of their operation is somewhat reminiscent of a rocket takeoff: the physical body reacts to the ejected powerful jet of gas, as a result of which it moves in the opposite direction. This is the basic principle of work. jet aircraft.

Newton's laws in jet propulsion

Engineers base their developments on the principles of the universe, first described in detail in the works of the outstanding British scientist Isaac Newton, who lived at the end of the 17th century. Newton's laws describe the mechanisms of gravity and tell us about what happens when things move. They are especially clear in explaining the movement of bodies in space.

Newton's second law determines that the force of a moving object depends on how much matter it contains, in other words, its mass and changes in the speed of movement (acceleration). This means that in order to create a powerful rocket, it is necessary that it constantly releases large amounts of high-speed energy. Newton's third law says that for every action there will be an equal in force, but the opposite reaction - opposition. Jet engines in nature and technology obey these laws. In the case of a rocket, the force of action is the matter that is ejected from the exhaust pipe. The countermeasure is to push the rocket forward. It is the force of the emissions from it that pushes the rocket. In space, where a rocket has practically no weight, even a small push from the rocket engines can make a large ship fly forward quickly.

Technique using jet propulsion

The physics of jet propulsion is that the acceleration or deceleration of a body occurs without the influence of surrounding bodies. The process occurs due to the separation of part of the system.

Examples of jet propulsion in technology are:

the phenomenon of recoil from a shot;
explosions;
blows during accidents;
recoil when using a powerful fire hose;
a boat with a water-jet engine;
jet plane and rocket.

Bodies create a closed system if they only interact with each other. Such interaction can lead to a change in the mechanical state of the bodies that form the system.

What is the action of the law of conservation of momentum?

For the first time this law was announced by the French philosopher and physicist R. Descartes. When two or more bodies interact, a closed system is formed between them. Any body in motion has its own impulse. This is the mass of the body multiplied by its speed. The total impulse of the system is equal to the vector sum of the impulses of the bodies in it. The momentum of any of the bodies inside the system changes due to their mutual influence. The total momentum of bodies in a closed system remains unchanged for various displacements and interactions of bodies. This is the momentum conservation law.

Examples of the operation of this law can be any collisions of bodies (billiard balls, cars, elementary particles), as well as bursting of bodies and shooting. When fired from a weapon, a recoil occurs: the projectile rushes forward, and the weapon itself is pushed back. Why is this happening? The bullet and the weapon form a closed system with each other, where the law of conservation of momentum works. When firing, the impulses of the weapon itself and the bullet change. But the total impulse of the weapon and the bullet in it before firing will be equal to the total impulse of the rolling weapon and the bullet fired after firing. If the bullet and the gun had the same mass, they would fly in opposite directions at the same speed.

The momentum conservation law has wide practical application. It helps to explain the jet propulsion, due to which the highest speeds are achieved.

Reactive motion in physics

The most striking example of the law of conservation of momentum is the jet propulsion carried out by a rocket. The most important part of the engine is the combustion chamber. In one of its walls there is a jet nozzle adapted for the release of gas arising from the combustion of fuel. Under the influence of high temperature and pressure, the gas exits the engine nozzle at high speed. Before the launch of the rocket, its momentum relative to the Earth is equal to zero. At the moment of launch, the rocket also receives an impulse that is equal to the impulse of the gas, but in the opposite direction.

An example of the physics of jet propulsion can be seen everywhere. During a birthday celebration, a balloon can easily become a rocket. How? Inflate the balloon by pinching the open hole to keep air from escaping. Now release it. The balloon will drive around the room with great speed, driven by the air escaping from it.

History of jet propulsion

The history of jet engines began as early as 120 years BC, when Heron of Alexandria designed the first jet engine - eolipil. Water is poured into a metal ball, which is heated by fire. The steam that escapes from this ball rotates it. This device shows jet propulsion. The priests used the engine of Heron to open and close the doors of the temple. Eolipil modification - Segner wheel, which is effectively used in our time for irrigation of agricultural land. In the 16th century, Giovani Branca introduced the world to the first steam turbine that operated on the principle of jet propulsion. Isaac Newton proposed one of the first designs for a steam car.

The first attempts to use jet propulsion in technology to move on the ground date back to the 15-17 centuries. Even 1000 years ago, the Chinese had rockets that they used as military weapon... For example, in 1232, according to the chronicle, in the war with the Mongols, they used arrows equipped with missiles.

The first attempts to build a jet aircraft began in 1910. The rocket research of past centuries was taken as a basis, which described in detail the use of powder boosters, which could significantly reduce the length of the afterburner and takeoff run. The chief designer was the Romanian engineer Anri Coanda, who built an aircraft based on a piston engine. The pioneer of jet propulsion in technology can rightfully be called an engineer from England - Frank Wheatle, who proposed the first ideas for creating a jet engine and received his patent for them at the end of the 19th century.

First jet engines

For the first time, the development of a jet engine in Russia was started at the beginning of the 20th century. The theory of the motion of jet vehicles and rocketry capable of developing supersonic speed was put forward by the famous Russian scientist K.E. Tsiolkovsky. The talented designer A.M. Lyulka managed to bring this idea to life. It was he who created the project of the first jet aircraft in the USSR, working with a jet turbine. The first jet aircraft were created by German engineers. Project creation and production were carried out in secret in disguised factories. Hitler, with his idea of \u200b\u200bbecoming a world ruler, involved the best designers in Germany to produce the most powerful weapons, including high-speed aircraft. The most successful of these was the first German jet, the Messerschmitt-262. This aircraft became the first in the world that successfully passed all the tests, took off freely and after that began to be mass-produced.

The aircraft had the following features:

The device had two turbojet engines.
A radar was located in the bow.
The aircraft's maximum speed reached 900 km / h.

Thanks to all these indicators and design features the first jet aircraft, the Messerschmitt-262, was a formidable weapon against other aircraft.

Prototypes of modern airliners

In the post-war period russian designers jet aircraft were created, which later became the prototypes of modern airliners.

The I-250, better known as the legendary MiG-13, is a fighter that A.I. Mikoyan worked on. The first flight took place in the spring of 1945, at that time the jet fighter showed a record speed of 820 km / h. The MiG-9 and Yak-15 jet aircraft were launched into production.

In April 1945, for the first time, the jet aircraft of P.O. Sukhoi - Su-5 took off into the sky, rising and flying at the expense of an air-jet motor-compressor and piston engine located in the tail of the structure.

After the end of the war and the surrender of Nazi Germany, the Soviet Union received German aircraft with jet engines JUMO-004 and BMW-003 as trophies.

First world prototypes

Not only German and Soviet designers were involved in the development, testing and production of new airliners. Engineers from the USA, Italy, Japan, Great Britain also created a lot successful projectsused jet propulsion in engineering. Among the first developments since different types engines include:

Non-178 is a German turbojet-powered aircraft that took off in August 1939.
GlosterE. 28/39 is an aircraft originally from the UK, with a turbojet engine, first took to the skies in 1941.
He-176 - a fighter created in Germany using a rocket engine, made its first flight in July 1939.
BI-2 is the first Soviet aircraft to be propelled by a rocket power plant.
CampiniN.1 is a jet aircraft created in Italy, which was the first attempt by Italian designers to move away from the piston analogue.
Yokosuka MXY7 Ohka ("Oka") with a Tsu-11 engine is a Japanese fighter-bomber, the so-called disposable aircraft with a kamikaze pilot on board.

The use of jet propulsion in technology served as a sharp impetus for the rapid creation of the following jet aircraft and the further development of military and civil aircraft construction.

GlosterMeteor - a jet fighter manufactured in Great Britain in 1943, played a significant role in the Second World War, and after its completion it served as an interceptor of German V-1 missiles.
The Lockheed F-80 is a US-made jet aircraft using an AllisonJ engine. These aircraft took part in the Japanese-Korean War more than once.
B-45 Tornado is a prototype of modern American B-52 bombers, created in 1947.
The MiG-15 is a follower of the recognized MiG-9 jet fighter, which actively participated in the military conflict in Korea, was produced in December 1947.
Tu-144 is the first Soviet supersonic air-jet passenger aircraft.

Modern jet vehicles

Every year, airliners are improving, because designers from all over the world are working to create a new generation of aircraft capable of flying at the speed of sound and at supersonic speeds. Now there are airliners capable of accommodating a large number of passengers and cargo, of enormous size and an unimaginable speed of over 3000 km / h, military aircraft equipped with modern combat gear.

But among this variety, there are several designs of record-breaking jet aircraft:

The Airbus A380 is the largest aircraft capable of accommodating 853 passengers on board, which is ensured by a double-deck structure. He is also one of the most luxurious and expensive airliners of our time. The largest passenger liner in the air.
Boeing 747 - for more than 35 years it was considered the most capacious double-decker airliner and could carry 524 passengers.
AN-225 Mriya is a cargo aircraft that boasts a carrying capacity of 250 tons.
LockheedSR-71 is a jet aircraft that reaches a speed of 3529 km / h during flight.

Aviation research does not stand still, because jet aircraft are the basis of the rapidly developing modern aviation. Several Western and Russian manned, passenger, unmanned jet-powered airliners are currently under design, and are scheduled to be released in the next few years.

Russian innovative developments of the future include the 5th generation PAK FA - T-50 fighter, the first copies of which will arrive at the troops presumably in late 2017 or early 2018 after testing a new jet engine.

Nature is an example of jet propulsion

The reactive principle of movement was originally prompted by nature itself. Its action is used by the larvae of some species of dragonflies, jellyfish, many mollusks - scallops, cuttlefish, octopuses, squids. They use a kind of "repulsion principle". Cuttlefish suck in water and throw it out so rapidly that they themselves make a leap forward. Squids using this method can reach speeds of up to 70 kilometers per hour. That is why this method of movement made it possible to call squid "biological rockets". Engineers have already invented an engine based on the movement of a squid. One example of the use of jet propulsion in nature and technology is a water cannon.

This is a device that provides movement using the force of water thrown out under strong pressure. In the device, water is pumped into the chamber, and then discharged from it through the nozzle, and the vessel moves in the opposite direction of the jet ejection. The water is drawn in with a diesel or gasoline engine.

The plant world also offers examples of jet propulsion. Among them are species that use this movement to spread seeds, such as the mad cucumber. Only outwardly, this plant is similar to the cucumbers we are used to. And the characteristic "rabid" it received because of the strange way of reproduction. Ripening, the fruits bounce off the stalks. As a result, a hole opens through which the cucumber shoots a substance containing seeds suitable for germination, applying reactivity. And the cucumber itself bounces up to twelve meters to the side opposite to the shot.

The manifestation of jet propulsion in nature and technology is subject to the same laws of the universe. Mankind is increasingly using these laws to achieve its goals not only in the Earth's atmosphere, but also in the vastness of space, and jet propulsion is a prime example of this.

The logic of nature is the most accessible and most useful logic for children.

Konstantin Dmitrievich Ushinsky (03.03.1823–03.01.1871) - Russian teacher, founder of scientific pedagogy in Russia.

BIOPHYSICS: REACTIVE MOTION IN LIVING NATURE

I invite readers of the green pages to look into fascinating world of biophysics and get to know the main principles of jet propulsion in wildlife... Today in the program: jellyfish cornerot - the largest jellyfish in the Black Sea, scallops, enterprising dragonfly larva, delicious squid with its unrivaled jet engine and wonderful illustrations performed by a Soviet biologist and animal artist Kondakov Nikolai Nikolaevich.

According to the principle of jet propulsion, a number of animals move in wildlife, for example, jellyfish, sea molluscs, scallops, dragonfly-rocker larvae, squid, octopus, cuttlefish ... Let's get to know some of them better ;-)

Reactive way of moving jellyfish

Jellyfish are one of the most ancient and numerous predators on our planet! The body of the jellyfish is 98% water and is largely composed of watered connective tissue - mesogleyfunctioning like a skeleton. The basis of the mesoglea is collagen protein. The gelatinous and transparent body of the jellyfish is shaped like a bell or umbrella (in diameter from a few millimeters up to 2.5 m). Most jellyfish move reactive waypushing water out of the umbrella cavity.

Jellyfish Cornerota (Rhizostomae), a detachment of coelenterates of the scyphoid class. Jellyfish ( up to 65 cm in diameter) are devoid of marginal tentacles. The edges of the mouth are extended into oral lobes with numerous folds that grow together to form a multitude of secondary oral openings. Touching the mouth blades can cause painful burnscaused by the action of stinging cells. About 80 types; live mainly in tropical, less often in temperate seas. In Russia - 2 types: Rhizostoma pulmo common in the Black and Azov seas, Rhopilema asamushi found in the Sea of \u200b\u200bJapan.

Scallop shellfish jet escape

Sea clams scallops, usually lying calmly at the bottom, when their main enemy approaches them - a delightfully slow, but extremely insidious predator - starfish - sharply squeeze the flaps of their shell, forcefully pushing water out of it. Using thus jet propulsion principle, they float up and, continuing to open and close the shell, can swim a considerable distance. If the scallop for some reason does not have time to be saved by its jet flight, the starfish grabs it with its own hands, opens the shell and eats it ...

Scallop (Pecten), a genus of marine invertebrates of the class of bivalve molluscs (Bivalvia). The scallop shell is rounded with a straight hinge edge. Its surface is covered with radial ribs diverging from the top. The shell valves are closed by one strong muscle. Pecten maximus, Flexopecten glaber live in the Black Sea; in the Sea of \u200b\u200bJapan and Okhotsk - Mizuhopecten yessoensis ( up to 17 cm in diameter).

Dragonfly Larva Jet Pump-Rocker Arm

Temper dragonfly larvae-rocker, or ashny (Aeshna sp.) Is no less predatory than its winged relatives. For two, and sometimes even four years, she lives in an underwater kingdom, crawls along a rocky bottom, tracking down small aquatic inhabitants, with pleasure including rather large-caliber tadpoles and fry in her diet. In moments of danger, the larva of a dragonfly-rocker breaks loose and jerks forward, driven by the work of a wonderful jet pump... Collecting water into the hind gut, and then abruptly throwing it out, the larva jumps forward, driven by the recoil force. Using thus jet propulsion principle, the dragonfly-rocker larva hides from the threat pursuing it with confident jerks and jerks.

Reactive impulses of the nervous "freeway" of squid

In all of the above cases (the principles of jet propulsion of jellyfish, scallops, dragonfly-rocker larvae), jerks and jerks are separated from each other by significant intervals, therefore, a high speed of movement is not achieved. To increase the speed of movement, in other words, number of reactive pulses per unit of time, it is necessary increased nerve conductionthat stimulate muscle contraction, serving a living jet engine... Such a high conductivity is possible with a large nerve diameter.

It is known that squid have the largest nerve fibers in the animal kingdom... On average, they reach 1 mm in diameter - 50 times that of most mammals - and they excite at a rate 25 m / s... And a three-meter squid dosidicus (he lives off the coast of Chile) the thickness of the nerves is fantastic - 18 mm... Nerves are thick as ropes! Brain signals - the causative agents of contractions - rush along the nervous "freeway" of the squid at a speed passenger car – 90 km / h.

Thanks to squid, research on the vital functions of nerves made rapid progress in the early 20th century. “And who knows- writes British naturalist Frank Lane, - maybe there are now people who owe the squid the fact that their nervous system is in a normal state ... "

The squid's speed and maneuverability are also explained by the excellent hydrodynamic forms body of an animal, for what squid and nicknamed the "live torpedo".

Squid (Teuthoidea), a suborder of cephalopods of the decapod order. The size is usually 0.25-0.5 m, but some types are the largest invertebrates (squid of the genus Architeuthis reach 18 m, including the length of the tentacles).
The squid's body is elongated, pointed at the back, torpedo-shaped, which determines the high speed of their movement, as in water ( up to 70 km / h), and in the air (squids can jump out of the water to a height up to 7 m).

Squid jet engine

Jet propulsion , which is now used in torpedoes, aircraft, rockets and space shells, is also characteristic of cephalopods - octopuses, cuttlefish, squid... Of greatest interest to technicians and biophysicists is squid jet engine... Pay attention to how simple, with what minimal cost of material, nature solved this difficult and still unsurpassed problem ;-)

Basically, the squid has two fundamentally different engines ( fig. 1a). When moving slowly, it uses a large diamond-shaped fin that periodically bends in the form of a traveling wave along the body. The squid uses a jet engine to throw quickly... The basis of this engine is the mantle - muscle tissue. It surrounds the body of the mollusk from all sides, making up almost half of its body volume, and forms a kind of reservoir - the mantle cavity - the "combustion chamber" of a living rocket, into which water is periodically sucked. In the mantle cavity are the gills and internal organs of the squid ( fig. 1b).

With reactive swimming the animal sucks in water through a wide open mantle gap into the mantle cavity from the boundary layer. The mantle gap is tightly “fastened” with special “cufflinks-buttons” after the “combustion chamber” of the living engine is filled with seawater. The mantle gap is located near the middle of the squid body, where it has the greatest thickness. The force that causes the movement of the animal is created by throwing a stream of water through a narrow funnel, which is located on the abdominal surface of the squid. This funnel, or siphon, - Living jet engine "nozzle".

The "nozzle" of the engine is equipped with a special valve and muscles can turn it. By changing the installation angle of the funnel-nozzle ( fig. 1c), the squid swims equally well, both forward and backward (if it swims backward, the funnel stretches along the body, and the valve is pressed against its wall and does not interfere with the water stream flowing out of the mantle cavity; when the squid needs to move forward, the free end of the funnel slightly lengthens and bends in a vertical plane, its outlet collapses and the valve takes a bent position). Reactive shocks and the suction of water into the mantle cavity follow one after another with an elusive speed, and the squid rushes like a rocket in the blue of the ocean.

Squid and its jet engine - picture 1

1a) squid - live torpedo; 1b) squid jet engine; 1c) the position of the nozzle and its valve when the squid moves back and forth.

The animal spends a fraction of a second on taking water and pushing it out. Sucking water into the mantle cavity in the aft part of the body during periods of slow motion by inertia, the squid thereby sucks the boundary layer, thus preventing the flow stall in the case of an unsteady flow regime. By increasing the portions of ejected water and increasing the contraction of the mantle, the squid easily increases the speed of movement.

The squid jet engine is very economicalso that it can reach speed 70 km / h; some researchers believe that even 150 km / h!

Engineers have already created squid jet engine: this is water cannonpowered by a conventional gasoline or diesel engine. Why then squid jet engine continues to attract the attention of engineers and is the subject of rigorous research by biophysicists? For work underwater, it is convenient to have a device that works without access to atmospheric air. The creative searches of engineers are aimed at creating a structure hydrojet enginelike air-jet…

Based on materials from wonderful books:
"Biophysics in physics lessons" Cecilia Bunimovna Katz,
and "Primates of the Sea" Igor Ivanovich Akimushkina

Kondakov Nikolay Nikolaevich (1908–1999) – soviet biologist, animal painter, candidate of biological sciences. The main contribution to biological science was the drawings he made of various representatives of the fauna. These illustrations have been included in many publications such as Great Soviet Encyclopedia, Red Book of the USSR, in animal atlases and in teaching aids.

Akimushkin Igor Ivanovich (01.05.1929–01.01.1993) – soviet biologist, writer and popularizer of biology, author of popular science books about animal life. Laureate of the All-Union Society Prize "Knowledge". Member of the Writers' Union of the USSR. The most famous publication of Igor Akimushkin is a six-volume book "Animal world".

The materials of this article will be useful to apply not only in physics lessons and biology, but also in extracurricular activities.
Biophysical material is extremely beneficial for mobilizing the attention of students, for turning abstract formulations into something concrete and close, affecting not only the intellectual, but also the emotional sphere.

Literature:
§ Katz Ts.B. Biophysics in physics lessons

§ § Akimushkin I.I. Primates of the sea
Moscow: publishing house "Mysl", 1974
§ Tarasov L.V. Physics in nature
Moscow: Publishing House "Education", 1988

Reactive motion in nature and technology

ABSTRACT IN PHYSICS

Reactive motion is a movement that occurs when any part of the body is separated from the body at a certain speed.

Reactive force arises without any interaction with external bodies.

The use of jet propulsion in nature

Many of us in our life have met while swimming in the sea with jellyfish. In any case, there are enough of them in the Black Sea. But few people thought that jellyfish use jet propulsion for movement. In addition, dragonfly larvae and some species of marine plankton move in this way. And often the efficiency of marine invertebrates when using jet propulsion is much higher than that of technological inventions.

Jet propulsion is used by many mollusks - octopuses, squid, cuttlefish. For example, a scallop clam moves forward due to the reactive force of a stream of water ejected from a shell when its valves are sharply compressed.

Octopus

Cuttlefish

Cuttlefish, like most cephalopods, moves in water in the following way. It draws water into the gill cavity through the lateral slit and a special funnel in front of the body, and then vigorously throws out a stream of water through the funnel. The cuttlefish directs the funnel tube to the side or back and rapidly squeezing water out of it, can move in different directions.

Salpa is a sea animal with a transparent body, when it moves, it receives water through the front opening, and water enters a wide cavity, inside which the gills are stretched diagonally. As soon as the animal takes a long sip of water, the hole closes. Then the longitudinal and transverse muscles of the salpa contract, the whole body contracts, and water is pushed out through the posterior opening. The reaction of the flowing jet pushes the salpa forward.

Of greatest interest is the squid jet engine. Squid is the largest invertebrate inhabitant of the ocean depths. Squids have reached the highest perfection in jet navigation. Their bodies even copy the rocket with their external forms (or, better to say, the rocket copies the squid, since it has an indisputable priority in this matter). When moving slowly, the squid uses a large diamond-shaped fin that bends periodically. He uses a jet engine for a quick throw. Muscle tissue - the mantle surrounds the body of the mollusk from all sides, the volume of its cavity is almost half the volume of the body of the squid. The animal sucks water into the mantle cavity, and then abruptly throws out a stream of water through a narrow nozzle and at high speed moves backward in jerks. In this case, all ten tentacles of the squid gather into a knot above the head, and it acquires a streamlined shape. The nozzle is equipped with a special valve, and the muscles can turn it, changing the direction of movement. The squid engine is very economical, it is capable of speeds up to 60 - 70 km / h. (Some researchers believe that even up to 150 km / h!) No wonder squid is called a "live torpedo". Bending the tentacles folded in a bundle to the right, left, up or down, the squid turns in one direction or the other. Since such a rudder is very large in comparison with the animal itself, its slight movement is enough for the squid, even at full speed, to easily dodge a collision with an obstacle. A sharp turn of the steering wheel - and the swimmer rushes in the opposite direction. So he bent the end of the funnel back and now slides head first. He bent it to the right - and the jet push threw it to the left. But when you need to swim fast, the funnel always sticks out right between the tentacles, and the squid rushes forward with its tail, like a crab would run - a runner endowed with the agility of a horse.

If there is no need to rush, squids and cuttlefish swim, undulating with fins - miniature waves run along them from front to back, and the animal glides gracefully, occasionally pushing itself also with a stream of water thrown out from under the mantle. Then the individual shocks that the mollusk receives at the time of the eruption of water jets are clearly visible. Some cephalopods can reach speeds of up to fifty-five kilometers per hour. It seems that no one has made direct measurements, but this can be judged by the speed and range of flying squid. And such, it turns out, there are talents in the relatives of octopuses! The best mollusk pilot is the stenoteutis squid. English sailors call it - flying squid ("flying squid"). It is a small animal the size of a herring. He pursues fish with such impetuosity that he often jumps out of the water, rushing like an arrow over its surface. He resorts to this trick and saving his life from predators - tuna and mackerel. Having developed the maximum jet thrust in the water, the pilot squid takes off into the air and flies over the waves for more than fifty meters. The apogee of a live rocket's flight lies so high above the water that flying squids often land on the decks of ocean-going ships. Four to five meters is not a record height to which squids rise into the sky. Sometimes they fly even higher.

The English shellfish researcher Dr. Rees described in a scientific article a squid (only 16 centimeters long), which, having flown a fair distance through the air, fell on the yacht's bridge, which was almost seven meters above the water.

It happens that many flying squids fall on the ship in a sparkling cascade. The ancient writer Trebius Niger once told a sad story about a ship that even sank under the weight of flying squids that fell on its deck. Squids can take off without acceleration.

Octopuses can fly too. French naturalist Jean Verany saw how an ordinary octopus accelerated in an aquarium and suddenly jumped out of the water backwards. After describing an arc five meters long in the air, he flopped back into the aquarium. Gathering speed to jump, the octopus moved not only due to the jet thrust, but also rowed with tentacles.
Baggy octopuses swim, of course, worse than squid, but at critical moments they can show a record class for the best sprinters. Staff at the California Aquarium tried to photograph an octopus attacking a crab. The octopus rushed to its prey so quickly that there was always lubricant on the film, even when shooting at the highest speeds. So the throw lasted hundredths of a second! Usually, octopuses swim relatively slowly. Joseph Seinle, who studied the migration of octopuses, calculated that an octopus, half a meter in size, floats on the sea at an average speed of about fifteen kilometers per hour. Each stream of water thrown out of the funnel pushes him forward (or rather, backward, since the octopus swims backwards) two to two and a half meters.

Jet propulsion can also be found in the plant world. For example, ripe fruits of “mad cucumber” at the slightest touch bounce off the stalk, and a sticky liquid with seeds is thrown out of the hole with force. At the same time, the cucumber itself flies in the opposite direction up to 12 m.

Knowing the law of conservation of momentum, you can change your own speed of movement in open space. If you are in a boat and have several heavy stones, then by throwing stones in a certain direction, you will move in the opposite direction. The same will happen in outer space, but there they use jet engines for this.

Everyone knows that a shot from a gun is accompanied by a recoil. If the weight of the bullet were equal to the weight of the gun, they would fly at the same speed. Recoil occurs because the rejected mass of gases creates a reactive force, thanks to which movement can be ensured both in air and in airless space. And the greater the mass and velocity of the outflowing gases, the greater the recoil force our shoulder feels, the stronger the reaction of the gun, the greater the reactive force.

Application of jet propulsion in technology

For many centuries, humanity has dreamed of space travel. Science fiction writers have offered a variety of means to achieve this goal. In the 17th century, the story of the French writer Cyrano de Bergerac about the flight to the moon appeared. The hero of this story reached the moon in an iron cart, over which he constantly tossed a strong magnet. Pulling towards him, the wagon rose higher and higher above the Earth until it reached the moon. And Baron Munchausen said that he climbed to the moon on a bean stalk.

At the end of the first millennium AD, China invented jet propulsion, which propelled rockets - bamboo tubes filled with gunpowder, they were also used as fun. One of the first car projects was also with a jet engine and this project belonged to Newton.

The author of the world's first project of a jet aircraft designed for human flight was the Russian revolutionary N.I. Kibalchich. He was executed on April 3, 1881 for participating in the assassination attempt on Emperor Alexander II. He developed his project in prison after the death sentence. Kibalchich wrote: “While in prison, a few days before my death, I am writing this project. I believe in the feasibility of my idea, and this belief supports me in my terrible situation ... I will calmly face death, knowing that my idea will not perish with me. "

The idea of \u200b\u200busing rockets for space flights was proposed at the beginning of this century by the Russian scientist Konstantin Eduardovich Tsiolkovsky. In 1903, an article by the teacher of the Kaluga gymnasium K.E. Tsiolkovsky "Exploration of world spaces with jet devices". This work contained the most important mathematical equation for astronautics, now known as the "Tsiolkovsky formula", which described the motion of a body of variable mass. In the future, he developed a scheme for a liquid-fuel rocket engine, proposed a multistage rocket design, and expressed the idea of \u200b\u200bthe possibility of creating entire space cities in near-earth orbit. He showed that the only device capable of overcoming gravity is a rocket, i.e. apparatus with a jet engine using fuel and an oxidizer located on the apparatus itself.

A jet engine is an engine that converts the chemical energy of a fuel into the kinetic energy of a gas jet, while the engine gains speed in the opposite direction.

The idea of \u200b\u200bK.E. Tsiolkovsky was implemented by Soviet scientists under the leadership of Academician Sergei Pavlovich Korolev. The first ever artificial Earth satellite was launched by a rocket in the Soviet Union on October 4, 1957.

The principle of jet propulsion is widely used in aviation and astronautics. In outer space, there is no medium with which the body could interact and thereby change the direction and modulus of its velocity, therefore, only jet aircraft, i.e. rockets, can be used for space flights.

Rocket device

The motion of the rocket is based on the law of conservation of momentum. If at some point in time any body is thrown away from the rocket, then it will acquire the same impulse, but directed in the opposite direction

Any rocket, regardless of its design, always has a shell and fuel with an oxidizer. The rocket shell includes a payload (in this case, a spacecraft), an instrument compartment, and an engine (combustion chamber, pumps, etc.).

The bulk of the rocket is fuel with an oxidizer (an oxidizer is needed to maintain fuel combustion, since there is no oxygen in space).

Fuel and oxidizer are pumped into the combustion chamber. Fuel, burning, turns into gas of high temperature and high pressure. Due to the large pressure difference in the combustion chamber and in outer space, gases from the combustion chamber rush out in a powerful jet through a specially shaped bell, called a nozzle. The purpose of the nozzle is to increase the speed of the jet.

Before the launch of the rocket, its impulse is zero. As a result of the interaction of the gas in the combustion chamber and all other parts of the rocket, the gas escaping through the nozzle receives a certain impulse. Then the rocket is a closed system, and its total impulse should be zero even after launch. Therefore, the shell of the rocket, all that is in it, receives an impulse equal in magnitude to the impulse of the gas, but opposite in direction.

The most massive part of the rocket, designed to launch and accelerate the entire rocket, is called the first stage. When the first massive stage of a multistage rocket runs out of fuel during acceleration, it is separated. Further acceleration is continued by the second, less massive stage, and to the speed previously achieved with the help of the first stage, it adds some more speed, and then separates. The third stage continues to increase the speed to the required value and delivers the payload to orbit.

The first person to fly in outer space was a citizen of the Soviet Union Yuri Alekseevich Gagarin. April 12, 1961 He circled the globe aboard the Vostok satellite

Soviet rockets were the first to reach the Moon, circled the Moon and photographed its invisible side from the Earth, the first to reach the planet Venus and deliver scientific instruments to its surface. In 1986, two Soviet spacecraft Vega-1 and Vega-2 examined Halley's comet at close range, approaching the Sun once every 76 years.

The best case, to demand correction ... "R. Feynman Even a brief review of the history of the development of technology shows an amazing fact of the avalanche development modern science and technology on the scale of the history of all mankind. If the transition of a person from stone tools to metal took about 2 million years; improvement of a wheel from a solid wood wheel to a wheel having a hub, ...

Which is lost in the depths of centuries, was, is and will always be the focus of national science and culture: and will always be open in the cultural and scientific movement to the whole World. "*" Moscow in the history of science and technology "- this is the name of the research project (led by S.S. Ilizarov), carried out by the Vavilov Institute of the History of Natural Science and Technology of the Russian Academy of Sciences with the support of ...

The results of his many years of work in various fields of physical optics. It laid the foundations for a new direction in optics, which the scientist called micro-optics. Vavilov paid great attention to questions of the philosophy of natural science and the history of science. He is credited with developing, publishing and promoting the scientific heritage of M.V. Lomonosov, V.V. Petrov, and L. Euler. The scientist headed the Commission on History ...

Today, most people associate jet propulsion in the first place, of course, with the latest scientific and technical developments... We know from physics textbooks that "reactive" means movement that occurs as a result of the separation of any part from an object (body). Man wanted to climb into the sky to the stars, he strove to fly, but he was able to fulfill his dream only with the advent of jet planes and stepped spaceships, capable of moving over great distances, accelerating to supersonic speeds, thanks to the modern jet engines installed on them. Designers and engineers developed the possibility of using jet propulsion in engines. Scientists also did not stand aside, offering the most incredible ideas and ways to achieve this goal. Surprisingly, this principle of movement is widespread in nature. It is enough to look around, you can notice the inhabitants of the seas and land, among which there are plants, the movement of which is based on the reactive principle.

History

Even in ancient times, scientists studied and analyzed with interest the phenomena associated with jet propulsion in nature. One of the first to theoretically substantiate and describe its essence was Heron, a mechanic and theoretician of Ancient Greece, who invented the first steam engine, named after him. The Chinese were able to find practical use for the reactive method. They were the first, taking as a basis the method of movement of cuttlefish and octopuses, in the 13th century they invented rockets. They were used in fireworks, making a great impression, and also, as signal flares, perhaps there were also combat missiles, which were used as rocket artillery. Over time, this technology came to Europe as well.

N. Kibalchich became the pioneer of modern times, having come up with the scheme of a prototype aircraft with a jet engine. He was an outstanding inventor and a staunch revolutionary, for which he was imprisoned. It was while in prison that he went down in history by creating his project. After his execution for active revolutionary activities and opposition to the monarchy, his invention was forgotten on the archival shelves. After some time, K. Tsiolkovsky was able to improve the ideas of Kibalchich, proving the possibility of exploring outer space by means of jet movement of spaceships.

Later, during the Great Patriotic War, the famous Katyushas, \u200b\u200bfield rocket artillery systems, appeared. That is how the people unofficially called the powerful installations that were used by the forces of the USSR with an affectionate name. It is not known for certain, in connection with which, the weapon received this name. The reason for this was either the popularity of Blanter's song, or the letter "K" on the body of the mortar. Over time, the front-line soldiers began to give nicknames to other weapons, thus creating a new tradition. The Germans also called this combat rocket launcher "Stalin's organ" for appearance, which resembled a musical instrument and a shrill sound that came from launching rockets.

Vegetable world

Representatives of the fauna also use the laws of jet propulsion. Most of the plants with such properties are annuals and juveniles: prickly carp, pedunculate garlic, touch-me-not core, double-cut pickle, three-veined meringia.

The prickly carp, aka mad cucumber, belongs to the pumpkin family. This plant grows to a large size, has a thick root with a rough stem and large leaves. It grows in the territory of Central Asia, the Mediterranean, in the Caucasus, quite common in the south of Russia and Ukraine. Inside the fruit, during the period of seed ripening, it is converted into mucus, which, under the influence of temperature, begins to ferment and release gas. Closer to ripening, the pressure inside the fetus can reach 8 atmospheres. Then, with a light touch, the fruit breaks off from the base and the seeds with liquid at a speed of 10 m / s fly out of the fruit. Due to its ability to shoot up to 12 m in length, the plant was named "lady's pistol".

The touch-me-not core is an annual widespread species. It is found, as a rule, in shady forests, along the banks along rivers. Once in the northeastern part of North America and South Africa, it successfully took root. The touch-sensitive core is propagated by seeds. The seeds of the touch-me-not core are small, weighing no more than 5 mg, which are thrown at a distance of 90 cm. Thanks to this method of seed distribution, the plant got its name.

Animal world

Reactive motion - interesting Factsconcerning the animal world. In cephalopods, reactive movement occurs by means of water exhaled through a siphon, which usually narrows to a small opening to obtain maximum expiratory flow. Water flows through the gills before exhalation, fulfilling the dual purpose of breathing and moving. Sea hares, otherwise gastropods, use similar means of movement, but without the complex neurological apparatus of the cephalopods, they move more awkwardly.

Some knight fish have also evolved jet propulsion by pumping water through their gills to complement their fin movement.

In dragonfly larvae, reactive force is achieved by displacing water from a specialized cavity in the body. Scallops and cardids, siphonophores, tunics (such as salps) and some jellyfish also use jet propulsion.

Most of the time, scallops lie quietly on the bottom, but in case of danger, they quickly close the valves of their shells, so they push out the water. This behavior mechanism also speaks of the use of the principle of reactive movement. Thanks to him, the scallops can float and move a great distance, using the technique of opening and closing the sink.

The squid also uses this method, absorbs water, and then with tremendous force pushing through the funnel moves at a speed of at least 70 km / h. Gathering the tentacles into one knot, the body of the squid forms a streamlined shape. Taking such a squid engine as a basis, the engineers have designed a water cannon. Water in it is sucked into the chamber, and then thrown out through the nozzle. Thus, the vessel is directed in the opposite direction from the ejected jet.

Compared to squid, salps use the most efficient engines, spending an order of magnitude less energy than squid. Moving, the salpa launches water into the opening in front, and then enters a wide cavity where the gills are stretched. After the pharynx, the opening is closed, and with the help of contracting longitudinal and transverse muscles that compress the body, water is ejected through the opening from behind.

The most unusual of all locomotion mechanisms is the common cat. Marcel Despres suggested that the body is able to move and change its position even with the help of only internal forces (not starting from anything and not relying on anything), from which it could be concluded that Newton's laws may be wrong. A cat that fell from a height could serve as proof of his assumption. During the fall upside down, it will still land on all its paws, this has already become a kind of axiom. Having photographed in detail the movement of the cat, we were able to examine in frames everything that it was doing in the air. We saw her paw movement, which caused a response from the trunk, turning in the other direction relative to the movement of the paw. Acting in accordance with Newton's laws, the cat landed successfully.

In animals, everything happens at the level of instinct, man, in turn, does it consciously. Professional swimmers, having jumped from the tower, manage to turn around three times in the air, and, having managed to stop the rotation, they straighten strictly vertically and dive into the water. The same principle applies to circus aerialists.

No matter how much a person tries to surpass nature, improving the inventions created by it, all the same, we have not yet reached the technological perfection when airplanes could repeat the actions of a dragonfly: hover in the air, instantly move backwards or move to the side. And all this happens at high speed. Perhaps a little more time will pass and planes, thanks to adjustments for the aerodynamics and jet capabilities of dragonflies, will be able to make sharp turns and become less susceptible to external conditions. Having looked at nature, man can still improve a lot for the benefit of technological progress.