How to Test the Performance of a Fume Hood Centrifugal Fan?

How to Test the Performance of a Fume Hood Centrifugal Fan?

Why Test the Performance of a Fume Hood Centrifugal Fan? The performance of a fume hood centrifugal fan has a significant impact on its operation and service life. Therefore, before using a fume hood centrifugal fan, it is essential to measure and understand its performance so that it can be used correctly and effectively to provide optimal service. Specifically, the primary objectives of testing the performance of fume hood centrifugal fans can be summarized as follows: (1) To become proficient in and master the methods for measuring the performance of fume hood centrifugal fans using performance testing equipment. (2) To learn the specific experimental methods and operational procedures. (3) Determine the performance of the fume hood centrifugal fan and convert the results into characteristic curves and parameters. In this experiment, the instruments, equipment, and specific test setup employ the suction test method, using a conical suction collector to measure the airflow of the fume hood centrifugal fan. The test air duct consists of a test tube, a throttle grid, a flow straightener, and other components. The experimental steps are as follows. (1) Connect the pressure gauge to the pressure measurement port of the test air duct using a connecting tube. Before connecting, check the pressure measurement tube for leaks. If leaks are present, do not use it. (2) Add weights to the torque measurement arm to keep it level. (3) Install the fan to be tested, remove the impeller, and start the motor. If the torque arm is not level, add weights until it is level, then record the no-load torque. (4) Install the propeller, connect the air supply tube to the test air tube, and rotate the coupling to check for any damage or friction between the propeller and the air inlet. (5) Start the motor and let it run for 10 minutes. During this time, keep the torque arm level. Once the fume hood-type centrifugal fan has stabilized, record the necessary parameter values. (6) Reduce the flow rate and vary the operating conditions of the fume hood centrifugal fan, recording the parameters for each set of operating conditions. Typically, 10 sets of operating conditions are measured. (7) Record atmospheric pressure and temperature before and after the experiment for comparison. The processing of experimental results includes the following: (1) Plot the aerodynamic performance curve based on the measurement data. (2) Convert the parameters obtained from the experiment into dimensionless quantities and plot the dimensionless performance curve.