Bubble Level Meter Air-Blowing Liquid Level Gauge for Precise Measurement of Liquid Level Height

The air-blowing level gauge is an instrument used to measure the liquid level. Its working principle is based on the relationship between the static pressure of the liquid and the liquid level height. The following are its main working principles and processes:

1. Working principle
The air-blowing level gauge calculates the liquid level height by passing a certain pressure of gas (usually compressed air) into the measuring tube and measuring the pressure change when the gas flows through the pipe.

- **Liquid static pressure formula**:
[
P = rho g h
]
Where:
- (P) is the static pressure of the liquid;
- (rho) is the density of the liquid;
- (g) is the acceleration of gravity;
- (h) is the liquid level height.

- **Core process**:
- Gas enters the tank or container through the air-blowing pipe.
- When the pressure of the gas reaches equilibrium and just offsets the static pressure of the liquid, the gas pressure at the pipe mouth is equal to the liquid pressure.
- Use a pressure sensor to measure the pressure value of the gas in the pipe, and combine the known liquid density and gravity acceleration to calculate the liquid level height.

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2. Equipment composition
The air-blowing liquid level gauge is mainly composed of the following parts:
- **Air blowing device**: used to generate and adjust the pressure of the air flow;
- **Air blowing tube**: inserted into the liquid, and its lower end opening position corresponds to the liquid level reference point;
- **Pressure sensor**: measures the gas pressure in the air blowing tube;
- **Display or transmitter**: converts the measured pressure into liquid level height and displays or outputs it.

3. Features and advantages

- **Advantages**:
- Suitable for measuring viscous or corrosive liquids because there is no direct contact between the air blowing tube and the sensor.
- Simple structure and easy maintenance.
- Can work in high temperature, high pressure and highly corrosive environments.

- **Disadvantages**:
- There are requirements for the quality of the gas source, and the gas must be free of impurities or moisture.
- The measurement accuracy is affected by the change in liquid density.
- The air blowing process may introduce slight disturbances, which may not be applicable to some sensitive liquids.

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4. Application scenarios
Air-blowing level gauges are widely used in industrial process control, such as:
- Corrosive liquid storage tanks in the chemical industry;
- Crude oil or sewage treatment in the petroleum industry;
- Tank level monitoring in the water treatment industry.

Air-blowing level gauges can achieve continuous measurement and monitoring of liquid levels, which are suitable for various complex working conditions.