The most quiet refrigerator
the quietest refrigerator is adsorption. The fact that the refrigerant in it moves through the heating Coil. The most quiet refrigerator is not very cheap and expensive, but it can work from a gas bottle. There is no difference where to get energy. Even mobile refrigerators to cars, powered from the network 12 and running through cooling semiconductor passing current, can not be compared with adsorption. In the latter case, you only hear the sound of the circulating refrigerant, whereas the gel, using the battery under the hood, require at least two fans and warm beauty.
the Adsorption refrigerators are not so rare, but not often known to the General public. Well, who would have thought that cooling can be achieved by combustion of gas? Currently, there is already the idea of creating an adsorption refrigerator operating through solar energy. No one knows exactly when was the first model. In fact, during the cold war, the unit was classified for use in military and space industry, because it seemed too good to be creating adsorption refrigerator. Information were removed from textbooks, and so continued until the conference in Paris in 1992. Some data about the first adsorption refrigerators can be obtained from specialized books published before 1960.
First of all, on terms. In the literature referred to as absorption and adsorption chillers. There is every reason to believe that this is related designs, working on the varieties of sorption, and some of the writers (we don't do for himself (herself) is mistaken, not knowing really what was going on. For us it is not so important as the fact of the existence of that type of equipment, which works through the absorption cycles and feedback refrigerant granules of adsorbent or a liquid absorbent. Because today we decided to answer the question, what refrigerators are the most quiet.
And the difference between phenomena that underlie their work, is as follows:
- Absorbent absorbs a substance throughout the volume.
- In the case of adsorption refers only to the surface layer, i.e., absorbable substance does not penetrate into the depths.
Taking into account such considerations, it is not difficult to understand the confusion in this section home appliances. There is every reason to believe that the liquid sorbent is called absorbent, and solid (granules) – adsorbent.
Principle of operation of the adsorption refrigerator
No sensible explanation of how it works is the most quiet refrigerator in a network can not be found. Very pleased with interesting excerpt from an old textbook, but it is without pictures. There are two technologies that are used in the adsorption refrigerators:
the Granules of the adsorbent absorb the refrigerant coming from the evaporator. This continues as long as there is media in the gas phase. Then it is necessary to vaporize the refrigerant, this adsorbent is heated. Steam enters the condenser where it turns into a liquid and releases heat. Then, the refrigerant is discharged on a special device and enters the evaporator. When the transition in the gas phase is absorbed by the heat 50 times more than you already have in the media. Due to this, the temperature in the refrigerating chamber is reduced. Granules of adsorbent stationary at all times during a working cycle, which is periodic switching of the heating element.
the questions arise:
- why the refrigerant cannot move in the opposite direction;
- how do you implement such a system without valves;
- as teh understands when the duty cycle has come to an end.
We see that this General description is rather vague, but the second method, where the absorption chiller refrigerant is ammonia, nothing better!
- as absorbent used distilled water, and the refrigerant is ammonia. To prevent corrosion inside the system is filled with sodium chromate, and the desired pressure difference creates hydrogen – in the area of the evaporator, its concentration is lower. Water is at the bottom of the absorber where it is absorbed ammonia in the gas phase coming from the evaporator. A concentrated solution is pumped into the boiler by Hermonassa. In the process of evaporating the ammonia evaporates much better than water because of its lower boiling point, resulting in a pair of his flock to the condenser. Vanished as the moisture is going reflux (sort of cooled external environment of the tube and flows into the absorber, which also comes gaseous ammonia from the evaporator. So the cycle is closed.
it is unclear how different aged partial pressure of hydrogen in the evaporator and the condenser, and the principle of operation of Hermonassa – and quite insoluble mystery. Otherwise, I would like to understand why the concentrated solution is fed into the boiler, and as he is separated from the weak solution. Let us presume that the temperature of the Heater is maintained at all rather big, so the water evaporates no worse than ammonia, but is deposited on the dephlegmator much better. And so it turns easier, less weak solution. And with Hermonassa any ideas does not even arise.
Disadvantages of adsorption refrigerators
the Noise parameters of adsorption refrigerators like a really limited to the gurgling of the refrigerant, but this type of equipment has its drawbacks:
- Consumes a lot of energy.
- Long enters the operating mode (on average half an hour).
- does Not tolerate different bends and warps relative to earth's gravity.
- Ammonia and other refrigerants, is dangerous, they have long abandoned compressor models.
So, to summarize we can say that firms that produce the most quiet refrigerators, something must answer all these questions. Today the technique is very popular among fishermen: it's better than freeze fish carbon dioxide fire extinguisher. However, complaints about the low reliability of the equipment, which according to scientists minds can work virtually forever, because it has no moving parts, give reason to think that not so smooth in the field of adsorption. Reviews of quiet fridges in General confirm all their advantages and disadvantages, but we have not yet mentioned the high price of the equipment. As noted by the users, and we would have fewer problems and greater reliability.
How to understand a quiet refrigerator or noisy
On all appliances are specific standards that specify which features should have the equipment to go one way or the other group. Often the interpretation of the laws intersect, sometimes contradict each other. One of the documents, which can be applied to a quiet refrigerators, is ST SEV 4672-84. Despite the antiquity of the document, according to some reports it is active. About refrigerators there are the following data that enables to classify:
- Up to 200 litres – 40 dB.
- From 200 to 400 liters – 43 dB.
- more Than 400 litres – 50 dB.
- Up to 200 litres – 42 dB.
- From 200 to 400 liters – 45 dB.
- more Than 400 litres – 55 dB.
- Up to 200 litres – 53 dB.
- From 200 to 400 liters – 55 dB.
- more Than 400 litres – 60 dB.
We see that the class of the refrigerator in terms of noise is determined by its volume. It should be noted that inverter compressors are now able to provide 42 dB (some expensive models from Liebherr reach 38 dB), but a lower level it has not seen. In this regard, the adsorption refrigerators clearly fall within group A. In them there is nothing to make a noise, only the rustling of the refrigerant bit. To choose the most quiet refrigerator, it is a synonym for adsorption. Here there is no options.
How to measure the noise of the fridge? The method is based on adjusting the sound pressure in such a way as to exclude from the spectrum of frequencies that does not hear the human ear. This applies primarily in compressors, which are often issued and ultrasound. As for the adsorption refrigerators, here and adjust do not have measured sound pressure and will be required parameter. For the purposes of the experiment you will need regular microphone and methods of work.
Usually the subject of a quiet refrigerator is installed in a room where there are no reflections of the sound. For living conditions, you must have the ceiling and carpets on the floor and walls. Part of the apparatus is determined according to ST SEV 1351-78 or ST SEV 1807-79. Then the refrigerator can be installed on any hard floor at a distance from the sound-reflecting wall 15 see, This can be the piece of painted concrete. The nearest angle should be at least 1.5 m Microphones are positioned as in the drawing.
d – not less than 1 m; a, b, c are chosen on the basis of reasonable. Surface area measurements by the formula:
S = 2 ( 2ac + 2ab + bc ), in fact, the area of the box minus the floor and rear concrete wall.
Before measuring the fridge works 6 hours on medium mode, then break for 10 minutes. After that, the machine starts up again, and after 3 minutes is measured. Processing of the results is conducted in document ST SEV 541-77 (GOST 23941-2002).
Thus, you can choose the quietest refrigerator, believing the manufacturer, or making his own dimension. And what is this? If you are in the house 6 microphones and instrument…