Nering Krzysztof, Kwiecień Arkadiusz, Nering Konrad
Faculty of Civil Engineering, Cracow University of Technology, 31-155 Cracow, Poland.
FlexAndRobust Systems Ltd., 31-155 Cracow, Poland.
Materials (Basel). 2024 Dec 3;17(23):5910. doi: 10.3390/ma17235910.
This study investigates the dynamic stiffness and damping characteristics of three polyurethane materials-PM, PS, and PST-using a comprehensive vibroacoustic testing approach. The aim is to examine material parameters such as dynamic stiffness, Young's modulus, critical damping factor, and the influence of sample irregularities on the accuracy of measurements. The study employs both experimental testing, in which cuboidal and cylindrical polyurethane samples were subjected to sinusoidal excitation, and finite element modeling (FEM) to simulate the test conditions in sample without irregularities. Results indicate that sample contact surface irregularities (even as low as ~0.04 mm) significantly impact the measured dynamic stiffness, with the effect intensifying for materials with higher Young's modulus values (above 5 MPa). Furthermore, cylindrical samples demonstrated more stable and repeatable measurements compared to cuboidal samples, where surface irregularities were tested in a more controlled environment. The findings underscore the need to consider sample geometry and irregularities in dynamic stiffness assessments to ensure better material evaluations. This work contributes valuable insights for the accurate modeling and testing of materials used in vibration isolation and sound insulation contexts.
本研究采用综合振动声学测试方法，研究了三种聚氨酯材料（PM、PS和PST）的动态刚度和阻尼特性。目的是研究诸如动态刚度、杨氏模量、临界阻尼因子等材料参数，以及样品不规则性对测量精度的影响。该研究既采用了实验测试（对长方体和圆柱形聚氨酯样品进行正弦激励），也采用了有限元建模（FEM）来模拟无不规则性样品的测试条件。结果表明，样品接触面的不规则性（即使低至约0.04毫米）会显著影响测量的动态刚度，对于杨氏模量值较高（高于5兆帕）的材料，这种影响会加剧。此外，与长方体样品相比，圆柱形样品的测量结果更稳定、可重复，长方体样品的表面不规则性是在更可控的环境中测试的。研究结果强调，在动态刚度评估中需要考虑样品几何形状和不规则性，以确保更好地评估材料。这项工作为准确建模和测试用于隔振和隔音环境的材料提供了有价值的见解。
