Specific detection methods for measuring wind speed and airflow using an anemometer
A. Air volume and wind speed detection must be carried out first. All purification effects are achieved under the designed air volume and wind speed.
B. Before testing, it is necessary to check whether the fan is operating normally and measure the dimensions of the tested air outlet and air duct on site.
C. For unidirectional flow (laminar flow) clean rooms, the air volume is determined by the product of the average wind speed of the room section and the clean product.
(Take a section 0.3m away from the high-efficiency filter perpendicular to the airflow as the sampling section, and set no less than 5 test points on the section with a spacing of no more than 0.6m. The arithmetic mean of all readings is taken as the average wind speed.) The measurement section of the vertical unidirectional flow (laminar flow) clean room is taken from a horizontal section 0.8m to 1m from the ground; The measurement cross-section of a horizontal unidirectional flow (laminar flow) clean room is taken from a vertical cross-section of 0.5m to 1m on the air supply surface; The number of test points on the cross-section should not be less than 10, and the spacing should not be greater than 2 meters, evenly arranged;
D. For air outlets equipped with filters, the air volume is determined by the product of the average wind speed of the outlet section and the net cross-sectional area of the outlet. (Calculate the average wind speed based on at least 6 uniformly arranged test points on the cross-section of the air outlet or the section of the auxiliary air duct.)
E. When there is a long branch pipe section on the windward side of the air outlet that has been or can be perforated, the air volume can be determined using the duct method. (Punch holes at least 3 times the pipe diameter or 3 times the length of the large side in front of the air outlet;)
F. For rectangular air ducts, divide the measurement section into several equal small sections, with each small section as close to a square as possible and a side length of no more than 200mm. The test points should be located at the center of the small section, but there should not be less than 3 test points on the entire section; For circular air ducts, the equal area ring method should be used to divide the measurement cross-section and determine the number of test points; Open a hole on the outer wall of the air duct and insert a thermal anemometer probe or pitot tube. (By measuring the dynamic pressure, it is converted into air volume.)
