In order to obtain complete information on the wind pressure on the surface of the model, people generally arrange dense measurement points on the surface. For this purpose, the researchers applied the multi-channel integrated pressure measurement system (referred to as the multi-channel pressure measurement system) to the wind tunnel pressure measurement test: the airflow in multiple pressure measurement pipes connected to the measurement points on the surface of the model is in the pneumatic manifold Pneumatic averaging is carried out in the middle, and then imported into the main pipe connected to the sensor. It must be recognized that the aerodynamically averaged peak pressure obtained with the pneumatic manifold is essentially different from directly adding the peak pressure measured at each point.
Since the peaks at each point do not occur simultaneously (ie, the correlation is not 1), directly adding the peak pressures at each point will result in overestimating the wind load on the structure. The multi-point average pulsating wind pressure measured by the multi-channel pressure measurement system is the instantaneous addition of the airflow of each input pipe of the pneumatic main, so that the wind pressure on the local area of ​​the model surface is more truly reflected. It can be seen that the use of a multi-channel pressure measurement system to measure pulsating wind pressure can not only expand the number of simultaneous measurement points, but also more realistically measure the relevant performance of the pulsating wind pressure on the model surface. The multi-channel pressure measurement system has been used to measure the average static pressure for a long time. In 1979, Surry and Stathopoulos used the multi-channel pressure measurement system to measure the multi-point aerodynamic average pulsating wind pressure.
With the development of the electronics field in recent decades, the emergence of sensors, scanning valves and other equipment has enabled people to further measure pulsating wind pressure to meet the needs of engineering practice. Due to the need for measurement, the pressure measurement pipeline system often has a certain length. After the airflow passes through the pressure measurement pipeline system to the sensor, the pulsating part of the pressure signal has been distorted (it is well understood that the average pressure will not be distorted), which causes the measurement result of the pulsating signal to be distorted. The distortion of the pulsating pressure signal can be attributed to the problem of the frequency response function (frequency response function for short) of the pressure measurement pipeline system.
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