Damping loss factor testing system
In the prediction model of structural noise, it is often necessary to input the damping loss factor (DLF) of materials and structures, which characterizes the rate of energy attenuation after loading and the state of energy balance. It is a very important parameter in statistical energy analysis.
In noise testing, it is often necessary to test the T60 of the acoustic cavity, which can well reflect the attenuation of the noise source in the acoustic cavity. The testing module for this parameter is very common in acoustic systems. However, for most modal testing software, there are few dedicated DLF testing modules for materials and structures. The prestigious VA-DLF is a specialized testing system used for DLF testing. It uses a force hammer to excite the measured object, record and analyze the response of each measurement point, calculate the average T60 of the decay curve through the attenuation of the response, and obtain DLF using an approximate formula.
Due to the use of a portable four channel testing system, the force hammer response of three measuring points can be tested simultaneously on site. The test configuration diagram is as follows:
● Hammer head self-calibration, adjusting the hammer head status by hitting it twice
● Check the effectiveness of tapping every time the test is conducted
● Simultaneously recording real-time data from 3 to 4 channels
● Simultaneous calculation and averaging of T60 within the frequency band
● Can directly calculate DLF
Recommended system configuration
● VA-DLF software
● MC3242 data acquisition instrument × 1
● IH02 Impact Hammer × 1
● SW13232 unidirectional accelerometer × 3