Repeatedly each of us heard the expression "ultrasound" - in this article we will look at what it is, how it is created, and what it is for.
The concept of "ultrasound"
Ultrasound is mechanical vibrations that are much higher than the frequency range that the human ear hears. Oscillations of ultrasound are somewhat reminiscent of a wave similar to light. But, unlike light-type waves, which propagate only in a vacuum, ultrasound needs an elastic medium - liquid, gas, or any other solid body.
Basic parameters of ultrasound
The main parameters of an ultrasonic wave are considered to be the wavelength and period. The time it takes for a full cycle is called the wave period and is measured in seconds.
The ultrasonic emitter is considered to be the most powerful generator of ultrasonic waves. A person cannot hear the ultrasonic frequency, but his body is able to feel it. In other words, the human ear perceives ultrasonic frequency, but the part of the brain responsible for hearing is unable to decipher this sound wave. Unpleasant to human hearinghigh frequency, but if you raise the frequency by one more range, then the sound will completely disappear - despite the fact that it is in the ultrasonic frequency. And the brain is making efforts to unsuccessfully decode it, because of this, a person has a terrible headache, dizziness, nausea and other not very pleasant sensations.
Generators of ultrasonic vibrations are used in all areas of technology and science. For example, ultrasound can not only wash clothes, but also weld metal. In the modern world, ultrasound is actively used in agricultural machinery to repel rodents, since the body of most animals is adapted to communicate with their own kind at an ultrasonic frequency. It should also be said that the ultrasonic wave generator is also capable of repelling insects - today many manufacturers produce this kind of electronic repellents.
Varieties of ultrasonic waves
Ultrasonic waves are not only transverse or longitudinal, but also surface and Lamb waves.
Transverse ultrasonic waves are waves that move perpendicular to the plane of the direction of velocities and displacements of body particles.
Longitudinal ultrasonic waves are waves whose movement coincides with the direction of velocities and displacements of the particles of the medium.
The Lamb wave is an elastic wave that propagates in a solid layer with free boundaries. It is in this wave that the oscillatory displacement of particles occurs both perpendicular to the plane of the plate and in the direction of motion of the wave itself. It is the Lamb wave -this is a normal wave in platinum with free boundaries.
Rayleigh (surface) ultrasonic waves are waves with elliptical motion of particles that propagate on the surface of a material. The speed of a surface wave is almost 90% of the speed of a transverse wave, and its penetration into the material is equal to the wavelength itself.
Using ultrasound
As mentioned above, the diverse use of ultrasound, in which its most diverse characteristics are used, can be conditionally divided into three areas:
- getting information;
- active effect on the substance;
- signal processing and transmission.
It should be taken into account that for each specific application it is necessary to select an ultrasound of a certain frequency range.
The effect of ultrasound on matter
If a material or substance falls under the active influence of ultrasonic waves, then this leads to irreversible changes in it. This is due to non-linear effects in the sound field. This type of impact on the material is popular in industrial technology.
Obtaining information using ultrasound methods
Ultrasonic methods are widely used today in various kinds of scientific research for a thorough study of the structure and properties of substances, as well as for a complete understanding of the processes taking place in them at the micro and macro levels.
All these methods are mainly based on the dependence of the speed of propagation and attenuation of acoustic waves on what is happening in themprocesses and properties of substances.
Signal processing and transmission
Ultrasonic generators are used to convert and analogize various kinds of electrical signals in all branches of radio electronics and to control light signals in optics and optoelectronics.
Do-it-yourself ultrasonic transducer
In the modern world, the ultrasonic generator is widely used. For example, in industry, ultrasonic baths are used to quickly and efficiently clean something. It should be said that this cleaning method has proven itself only from the best side. Today, the ultrasonic generator is gaining popularity in other applications as well.
Assembling an UZG scheme to scare away dogs
Many residents of the country's megacities daily face a rather tangible problem of meeting a pack of stray dogs. It is impossible to predict the behavior of the flock in advance, so UZG will come to the rescue here.
In this article we will analyze how to make an ultrasonic generator with your own hands.
To create an ultrasound at home, you will need the following details:
- circuit board;
- mirkoschema;
- radio engineering elements.
It will not be difficult to assemble the circuit by yourself. In order to be able to control the impulses, it is necessary to fix the radio component microcircuit with a soldering iron to the specific legs.
Let's analyze the constructionhigh power ultrasonic frequency generator. The D4049 microcircuit, which has 6 logical intertors, works as an ultrasonic frequency generator.
Foreign microcircuit can be replaced with an analogue of domestic production K561LN2. To adjust the frequency, a 22k regulator is required, with the help of its US it can be reduced to an audible frequency. The output stage, thanks to 4 medium-power biopolar transistors, receives signals from the microcircuit. There are no special conditions for choosing transistors, the main thing here is to choose complementary pairs that are as close as possible in terms of parameters.
Almost any RF head that has a power of 5 watts or more can be used as a radiator. The ideal option would be domestic heads such as 10GDV-6, 10GDV-4 or 5GDV-6, they can easily be found in all acoustic systems manufactured in the USSR.
The self-made circuit of the ultrasonic generator remains only to be hidden in the case. A metal reflector will help control the power of the ultrasonic generator.
Ultrasonic generator circuit
In the modern world, it is customary to use an ultrasonic generator to repel dogs, insects, rodents, as well as for high-quality washing. UZG is also used to significantly reduce the time spent on washing and etching printed circuit boards. Chemical processes in the liquid proceed much faster due to cavitation.
The USG circuit is based on two rectangular pulse generators and a power amplifierbridge type. On logical elements of type DD1.3 and DD1.4, a tunable pulse generator of ultrasonic frequency of the meander shape is installed. It should be remembered that its operating frequency directly depends only on the total resistance of resistors R4 and R6, as well as on the capacitance of capacitor C3.
Remember the rule: the lower the frequency, the greater the resistance of these resistors.
On the elements DD1.1 and DD1.2, a low-frequency generator is made, which has an operating frequency of 1 Hz. The generators are interconnected by means of resistors R3 and R4. In order to achieve a smooth change in the frequency of the high-frequency generator, you need to use capacitor C2. One secret should also be remembered here - if capacitor C2 is shunted using switch SA1, then the frequency of the high-frequency generator will become constant.
The use of ultrasound: the widest scope of application
As we all know, ultrasound is not used anywhere in the modern world. Surely each of us at least once in his life underwent an ultrasound procedure (ultrasound examination). It should be added that it is thanks to ultrasound that doctors can detect the occurrence of diseases of human organs.
Ultrasound is actively used in cosmetology for effective cleansing of the skin not only from dirt and fat, but also from the epithelium. For example, ultrasonic phonophoresis is successfully used in beauty salons for nutrition and cleansing, as well as for moisturizing and rejuvenating the skin. The technique of using ultrasonic phonophoresis enhances the protective mechanisms of the skin due to the action of an ultrasonic wave. Cosmetic procedures withThe use of ultrasound is considered universal and suitable for all skin types. Ultrasonic phonophoresis echoes miracles!
The ultrasonic steam generator is actively used not only in Turkish hammams, Finnish saunas, but also in our modern Russian baths. Thanks to steam, our body is effectively cleansed of invisible dirt, our body gets rid of toxins and toxins, skin and hair are healed, steam has a positive effect on the human respiratory system.
Artificial fog generators are actively used to increase indoor air humidity, which has a beneficial effect on the climate in the apartment. This becomes especially relevant in the cold season, when central heating dries out the air. Artificial fog generators are used both in residential premises and in a terrarium or winter garden. Experts advise to have an ultrasonic fog generator for people with respiratory diseases or those prone to allergic diseases.
Conclusion
In home use, an ultrasonic steam or fog generator is a very useful device that will not only create comfort and coziness, but will also be able to enrich the air with invisible vitamins, light negative air ions, which are so numerous on the seashore, in the mountains or in the forest and very little inside our apartments. And this, in turn, will help to increase the emotional state and improve he alth.
