Negative pressure is a state in which the gas pressure is lower than the normal pressure.
Connection: Positive pressure and negative pressure exist in opposition.
Difference:
1, different functions
Positive pressure refers to the state that the gas is higher than normal pressure (that is, one atmospheric pressure). For example, when inflating a bicycle or car tire, a positive pressure is generated at the outlet end of the pump.
Negative pressure is a state of gas pressure lower than normal pressure (that is, one atmosphere).
2. Different applications
The use of positive pressure is usually related to this concept in industry, especially in the selection of micro pumps (such as micro booster pump, micro air pump, micro air pump, micro gas circulating pump, micro air pump, micro air pump, etc.). ).
The use of negative pressure is very common, people often make a certain part of the space appear negative pressure, so they can use the ubiquitous atmospheric pressure instead of efficiency.
3. Different transmission power
The positive pressure gas transmission experiment was carried out with different lengths of beam tubes. The experimental and theoretical calculation results show that the positive pressure conveying power is 4~3 times of the negative pressure conveying power, and the positive pressure conveying gas not only shortens the gas conveying time, but also ensures the constant gas concentration. The data measured by positive pressure beam tube can truly reflect the spontaneous combustion state of coal.
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