The 200KHz ultrasonic gas flow transducer is a non-contact, high-precision core component for gas flow measurement, widely used in natural gas, coal gas, and other gas flow monitoring applications. It emits ultrasonic signals at a 200KHz frequency and measures gas flow velocity using the time-of-flight method or Doppler effect principle, featuring high accuracy, wide measurement range, and strong anti-interference capabilities.

I. Core Working Principle

1. Time difference method

The sensor emits ultrasonic signals, and there is a difference (△t) in propagation time in the downstream and upstream directions, which is calculated through the formula

 The flow velocity (v) is calculated by the formula: V = L · △t / (t1 · t2) · cosθ, where L is the probe spacing and θ is the angle between the acoustic wave and the fluid direction.

Advantages: Suitable for clean gases, with accuracy up to +0.5%, and a wide range ratio (1:160~1:350).

2. Doppler Effect Method

The reflection of ultrasound by suspended particles or bubbles in a gas causes a frequency shift (△f) between the reflected and emitted frequencies, which can be calculated using the formula

The formula Δf = -2ftv*cosθ/c is used to calculate the flow velocity (v).

Advantages: Suitable for gases containing impurities or bubbles, with strong anti-interference capability.

II. Key Technical Parameters (Taking a Typical Model as an Example)

III. Application scenarios and selection suggestions

1. Urban gas metering

Requirement: Wide range, anti impurity (such as condensate water, dust).

Recommendation: A 200KHz transducer (such as MIC Meter AF0200K1) with a wide range ratio (1:160) and strong penetration.

2. Industrial process control

Requirement: High precision, high temperature and high pressure resistance.

2. Industrial process control

Requirement: High precision, high temperature and high pressure resistance.

Recommendation: Titanium alloy probe (with strong corrosion resistance),

Supports temperatures ranging from -50 ℃ to 420 ℃ and a pressure of 25MPa.

3. Intelligent gas meter

Requirement: Low power consumption and miniaturization.

Recommendation: MIC Meter AF0200K1, AF0500K1, small size, stable operation.

IV. Key points for installation and maintenance

1. Installation specifications

Requirements for straight pipe section: upstream ≥ 30D, downstream ≥ 10D (D is the diameter of the pipeline), avoiding interference from valves and elbows.

Coupling agent usage: Ensure good coupling between the probe and the pipeline, avoiding bubbles or gaps (it is recommended to use specialized ultrasonic coupling agents).

Angle calibration: The angle error between the sound wave and the fluid direction should be ≤± 1 °, otherwise the flow error will increase.

2. Common faults and solutions

Unstable reading: Check if the pipeline is filled with fluid or if the probe is installed at the weld/rust area.

No signal or weak signal: Clean the oil/rust on the surface of the probe, or replace the damaged probe.

Decreased accuracy: Regular calibration (recommended once a year), or check if the temperature and pressure compensation module is functioning properly.

V. Development Trends

1. Intelligence

Integrated IoT technology, supporting remote monitoring and fault warning.

Built in AI algorithm, realizing dynamic flow field compensation and self diagnosis function.

2. Material innovation

Using composite materials such as ceramics and titanium alloys to enhance corrosion resistance and high temperature resistance.

Develop low-power probes (with driving voltage as low as 5Vp-p) to extend battery life.

3. Multi channel technology

The large-diameter pipeline adopts a multi probe array (such as a 6-channel design) to eliminate the influence of uneven flow field, and the accuracy is improved to ± 0.2%.