Anemometer probe selection method

The anemometer commonly used measuring instruments have certain applications in many fields, among which the anemometer probe is divided into two types: a thermal probe and a rotary probe, both of which are probes of an anemometer. There are still big differences between the two. How should the anemometer choose the correct probe to use? Let's look at it together.

1 Anemometer Thermal Probe The anemometer's thermal probe works on the principle that a cold-impinging air stream carries heat away from the thermal element, and with a regulating switch that maintains a constant temperature, adjusting the current and the flow rate is proportional. When thermal probes are used in turbulent flow, the air flow from all directions strikes the heat element at the same time, which affects the accuracy of the measurement results. When measured in turbulent flow, the thermal anemometer flow sensor is often higher than the rotary probe. The above phenomena can be observed during the pipeline measurement. Depending on the design of the turbulence in the management pipeline, it can even occur at low speeds. Therefore, the anemometer measurement process should be performed on the straight part of the pipeline. The starting point of the straight part should be at least 10 × D before the measuring point (D = pipe diameter in CM); the ending point is at least 4 × D after the measuring point. The fluid cross section must not have any blockage. (corners, resuspended, objects, etc.)

2 Anemometer Rotary Probe Anemometer Rotary probe working principle is based on the transformation of the rotation into electrical signals, first through a proximity sensor beginning, "count" the rotation of the runner and generate a pulse series, and then After the detector conversion processing, you can get the speed value. The anemometer's large-diameter probe (60mm, 100mm) is suitable for measuring turbulence in medium and small flow rates (eg at the outlet of pipes). The anemometer's small-caliber probe is more suitable for measuring air flow with a cross-section greater than 100 times more than the cross-section of the explorer.