What is an Anemometer?

An anemometer is an instrument that measures air velocity. There are many types of it, and the most commonly used one in meteorological stations is the wind cup anemometer, which consists of three parabolic empty cups fixed on the bracket at 120° to each other to form the sensing part, and the concave surfaces of the empty cups are all in one direction. The entire sensing part is installed on a vertical rotating shaft, and under the action of wind force, the wind cup rotates around the rotating shaft at a speed proportional to the wind speed. Next, we will introduce you to the knowledge of anemometer.

Advantage

Anemometers have many advantages, the following are some of the more important ones:

1. Small size, little interference to the flow field.
2. Wide application range. It can be used not only for gas but also for liquid, and can be used in subsonic, transonic and supersonic flow of gas.
3. High measurement accuracy and good repeatability.
4. In addition to measuring the average speed, it can also measure the pulsation and turbulence. In addition to measuring unidirectional motion, velocity components in multiple directions can be measured simultaneously.

How to maintain anemometer？

In addition to maintaining the accuracy of daily data, the following points should also be paid attention to during daily maintenance and use:

1. It is forbidden to use the anemometer in a flammable gas environment.
2. It is forbidden to place the anemometer probe in flammable gas. Otherwise, fire or even explosion may result.
3. Please use the anemometer correctly according to the requirements of the instruction manual. If used improperly, it may cause electric shock, fire and sensor damage.
4. During use, if the anemometer emits abnormal smell, sound or smoke, or liquid flows into the anemometer, please shut down immediately and take out the battery. Otherwise, there will be danger of electric shock, fire and damage to the anemometer.
5. Do not expose the probe and anemometer body to the rain. Otherwise, there may be danger of electric shock, fire and personal injury.
6. Do not touch the sensor inside the probe.
7. When the anemometer is not in use for a long time, please take out the internal battery. Otherwise, the battery may leak and cause damage to the anemometer.
8. Do not place the anemometer in a place with high temperature, high humidity, dust and direct sunlight, as this will cause damage to the internal components or deterioration of the performance of the anemometer.
9. Do not wipe the anemometer with volatile liquid, which may cause deformation and discoloration of the anemometer shell. If the surface of the anemometer is stained, it can be wiped with a soft cloth and neutral detergent.
10. Do not drop or put heavy pressure on the anemometer.
11. Do not touch the sensor part of the probe when the anemometer is charged, this will affect the measurement results or cause damage to the internal circuit of the anemometer.

Application

The anemometer has a wide range of applications and can be used flexibly in all fields. It is mainly used in electric power, steel, petrochemical, energy-saving and other industries. There are other applications in the Beijing Olympic Games, such as sailing competitions, rowing competitions, field shooting competitions, etc., all of which need to be measured by anemometers.

The hot wire anemometer 0.1~25 m/s is relatively advanced. In addition to measuring wind speed, it can also measure wind temperature and air volume. There are many industries that need to use anemometers, recommended industries: fishing industry, various fan manufacturing industries, industries that require ventilation and exhaust systems, etc.

Different seasons and different geographical conditions will cause the wind direction in the atmosphere to change constantly. For example, the wind direction at the beach is different day and night, and there are different monsoons in winter and summer. Studying wind direction can help us predict and study climate changes, and we need to use anemometers at this time. The design of the anemometer is mostly in the shape of an arrow, but also in the shape of an animal, like a rooster. The arrow part of the anemometer will rotate with the wind direction.

How to measure wind speed and volume?

Specific detection methods of wind speed and air volume

1. Air volume and wind speed detection must be carried out first. All purification effects are obtained under the designed air volume and wind speed.
2. Before testing, check whether the fan is operating normally. The size of the air outlet and air duct to be tested must be measured on the spot.
3. For a unidirectional flow (laminar flow) clean room, the air volume should be determined by the method of average wind speed and clean product.

(Take the section 0.3m away from the high-efficiency filter and perpendicular to the airflow as the sampling section. According to the regulations that the distance between test points should not be greater than 0.6m, set no less than 5 test points on the section, and take the arithmetic mean of all readings as the sampling section. Average wind speed.)

The measurement section of the vertical unidirectional flow (laminar flow) clean room is taken from the horizontal section of 0.8m~1m from the ground, and the measurement section of the horizontal unidirectional flow (laminar flow) clean room is taken from the air supply surface of 0.5m~1m vertical section of . The number of test points on the section should not be less than 10, and the distance should not be greater than 2m, and they should be evenly arranged.

4. For the tuyere with a filter, the air volume is determined by the product of the average wind speed of the tuyere section and the net cross-sectional area of the tuyere. (The average wind speed can be obtained from no less than 6 uniformly arranged test points on the section of the tuyere or the section of the auxiliary air duct.)
5. When there is a long branch pipe on the windward side of the tuyere and holes have been or can be drilled, the air volume can be determined by the air duct method. (Drill holes not less than 3 times the pipe diameter or 3 times the length of the large side before the air outlet.)
6. For rectangular air ducts, divide the measured section into several equal small sections, each small section is as close to a square as possible, the side length is not more than 200mm, the test point is located in the center of the small section, but the entire section should not be less than 3 tests point. For circular air ducts, the measuring section shall be divided and the number of test points shall be determined by the equal-area circular method. Open a hole on the outer wall of the air duct and insert the thermal anemometer probe or tube. (Converted to air volume by measuring dynamic pressure.)