Jigao Air Conditioning: How to measure and adjust the airflow organization in a room?
Released by Beijing Jigao Air Conditioning Maintenance Center on September 9, 2011.
The measurement and adjustment of airflow organization is the key to whether the four degrees of air (i.e., air temperature, relative humidity, airflow velocity, cleanliness) meet the design requirements. Reasonable airflow organization can make the temperature and humidity distribution in the regulated room uniform, the airflow speed appropriate, providing people with a good living and working environment.
(1) Preparations and requirements before measurement: The total air volume and total air pressure of the central air conditioning system should reach the design requirements, the air ducts of each main pipe and branch pipe and the air outlet of each room should reach the design requirements, and the air supply status should reach the design requirements. At this time, preparations for debugging the airflow organization in the room can be carried out.
1. Correct the test adjustment instruments and components.
2. Determine the method for measuring and adjusting the airflow organization in the room.
3. Start the system fan, and all equipment of the air conditioning system begin to operate normally.
4. Measure and check again whether the wind volume of the door and air outlet meets the design requirements.
(2) Measurement items and contents:
① Due to different intake forms, the measurement methods are also different. First, the method of measuring airflow organization must be determined.
② There are two types of measurement point layouts: plane measurement point layout and longitudinal section measurement point layout. The plane measurement point layout determines the distance and height of the measurement points according to the area and flow rate of the air outlet. The arrangement of longitudinal section measurement points generally arranges one measurement point every (0.2-0.5m).
③ Measurement contents and items include airflow pattern, velocity distribution, temperature distribution, degree of temperature attenuation, static pressure box static pressure distribution, etc.
(3) Measurement methods:
① There are generally two methods for measuring airflow patterns: the smoke method uses a smoking agent to emit smoke and observe the direction and shape of the smoke; the point-by-point drawing method ties synthetic fiber threads to the measuring rod to see how the synthetic fiber threads flutter at each point.
② The measurement method for airflow velocity distribution is to use a thermoelectric anemometer bound to the measuring rod to measure wind speed. The selection of measurement points is the same as the point-by-point drawing method.
③ Temperature distribution measurement selects plane measurement points and uses a thermocouple thermometer to measure the temperature at each point; then selects longitudinal section measurement points and uses a thermocouple thermometer to measure the temperature at each point. And calculate and draw the curve of the degree of temperature attenuation.
④ Static pressure distribution measurement selects 2~3 measurement cross-sections at different distances from the orifice plate in the static pressure box, distributes points layer by layer, measures the static pressure values of the three layers of points in the static pressure box, and the changes of static pressure in the longitudinal and transverse directions can be seen. Beijing Jigao Air Conditioning Maintenance Center.