Research on thermal insulation structure of piezoelectric active vibration suppression system in cryogenic wind tunnel

The cryogenic wind tunnel test has emerged as the primary method for acquiring the aerodynamic characteristics of aircraft. Nevertheless, within the cryogenic wind tunnel, the high flow velocity, low temperature, and complex flow significantly degrade the performance of the piezoelectric active vibration suppression system. This situation poses challenges to the accurate measurement of the aerodynamic parameters of the aircraft model. Consequently, this paper puts forward a composite multi-layer insulation structure for the active vibration suppression system, which is based on finite-element transient thermal analysis. The key parameters of the thermal insulation structure are optimized using the genetic algorithm to enhance both the mechanical properties and the thermal insulation capacity of the structure. Finally, a test was conducted by constructing a low-temperature test platform. The test results demonstrate that the designed insulation structure decreases the cooling rate of the active vibration suppression system by 97% and improves the overall temperature uniformity.