Nguyên tắc của của an máy đo gió và làm thế nào để sử dụng nó
Đầu dò lựa chọn của máy đo gió% 3a Phép đo phạm vi của dòng chảy vận tốc từ % 7b% 7b% 7b2}}% 7d% 7d to 1{{8% 7d}0m/s can be chia thành ba phần: thấp tốc độ: 0 to 5m/s; Medium speed: 5 to 40m/s; High speed: 40 to 100m/s. Nhiệt Nhạy Đầu dò Of The Máy đo gió Is Used for Precise Measurement From 0 To 5m% 2fs% 3b The Rotary Probe of The The Anemometer Has the most ideal effect in measuring measuring flow velocities ranging from 5 to to 40m/s; And using a pitot tube can achieve the best results in the high-speed range. An bổ sung tiêu chuẩn cho lựa chọn dòng chảy tốc độ đầu dò của an máy đo gió chính xác là là nhiệt kế được sử dụng bởi nhiệt cảm biến của máy đo gió tại nhiệt độ của xấp xỉ cộng % 7b% 7b13% 7d% 7dC. Cánh quạt đầu dò của đặc biệt được thiết kế máy đo gió có thể đạt 350C. Pitot ống được sử dụng cho nhiệt độ trên cộng 350C.
The working principle of the thermal probe of the thermal probe anemometer is based on the cold shock airflow take away the heat on the thermal element. With the help of a regulating switch, the temperature ispt constant, kept constant, and the regulating current is proportional to the flow rate. When using a thermosensitive probe in turbulence, airflow from all directions impacts the thermal element, which can affect the accuracy of the measurement results. When meagauing in turbulence, the reading of the flow velocity sensor of the thermal anemometer is often higher than that of the rotary probe. The above phenomena can be observed in touring pipeline measurement. According to different designs for managing pipeline turbulence, it can even happen at low speeds.
Do đó, the anemometer measurement process nên be carried out on the straight section of the pipeline. The starting point of the straight section should be at least 10 times before the measurement point × D (D=pipeline diameter, in CM); The endpoint should be at least 4 after the measurement point × Location D.
The fluid cross-section must not have any obstruction. The working principle of the rotary probe of the anemometer is based on converting the rotation into an electrical signal. After passing through a proximity sensing start, the rotation of the rotary wheel is "counted" and a pulse series is generated, which is then converted and processed by the detector to obtain the rotational speed value. Đường kính lớn đầu dò của máy đo gió (60mm% 2c 100mm) là phù hợp cho đo lường nhiễu loạn tại trung bình và nhỏ dòng chảy tỷ lệ (như vậy as at đường ống đầu ra). nhỏ cỡ nòng đầu dò của máy đo gió là nhiều hơn phù hợp cho đo luồng không khí với a mặt cắt ngang diện tích lớn hơn hơn 100 lần đó của thăm dò đầu.
Máy đo gió Lựa chọn Hướng dẫn% 3a Định vị của Máy đo gió trong Không khí Dòng chảy% 3a The correct điều chỉnh vị trí of the anemometer's quay đầu dò is that the airflow direction is parallel to the rotary axis. When the probe is lighttly rotated in the airflow, the reading will change suit. When the reading reaches its maximum value, it chỉ ra that the probe is in the correct measurement position. Khi đo in a pipeline, the distance from the starting point of the straight part of the pipeline to the measurement point should be greater than 0}XD, and the influence of turbulence on the thermal sensitive probe and pitot tube of the anemometer is retương đối small. Anemometer for measuring airflow velocity in pipelines: Practice has proven proven that the 16mm probe of the anemometer is the most widely used. Nó kích thước đảm bảo tốt tính thấm và có thể chịu được dòng chảy tỷ lệ lên đến 60m% 2fs.
The measurement of airflow velocity in pipelines is one of the feasible measurement methods, and the indirect measurement regulation (grid measurement method) is applicable to air measurement. Measurement of anemometer in exhaust extraction: The ventilation port will greatly change the relatively balanced distribution of airflow in the pipeline: a high-speed zone will be generated on the surface of the free ventilation port, while the rest will be a low-speed zone, and vortices will be generated on the grid. According to different design methods of the grid, the airflow cross-section is relatively stable at a certain distance (about 20cm) in front of the grid.
In this case, measurements are usually made using the caliber wheel of a high wind speed instrument. Because larger apertures can average uneven flow rates and calculate their average values over a larger range. The anemometer uses a volumetric flow funnel for measurement at the exhaust port: even if there is no interference from the grid at the exhaust point, the air flow path also has no direction, and its airflow cross-section is extremely uneven. The reason for this is the local vacuum inside the pipeline, which funnels the air out into the air chamber. Even in the area close to the extraction, there is no location that meets the measurement conditions for measurement operations.
By using a measuring funnel, a fixed cross-section that meets the flow velocity measurement conditions can be generated at a certain distance in front of the disc valve. The center of the cross-section can be measured and fixed, and the center of the cross-section can be measured and fixed here. The measured value obtained by the flow rate probe is multiplied by the funnel coefficient to calculate the extracted volumetric flow rate.
