低温环境下高寒列车材料阻尼特性的试验

摘要

低温环境下，高速列车阻尼材料阻尼性能大大降低。为此，通过试验研究高寒列车现有四种阻尼材料温变、频变特性。测试温度包括常温、-10°C和-25°C，分析频率高达850 Hz。通过有限元方法计算无阻尼板件结构的模态频率和振型，并采用力锤敲击系统测试喷涂不同阻尼材料后的四种阻尼复合板件，得到结构模态频率、振型和阻尼比。结合仿真和试验实测振型结果，获得850 Hz内57阶模态阻尼比。对比四种阻尼复合板件结构在三种温度工况下的阻尼比变化规律。结果表明，现车用阻尼材料在常温和中频下具有较好的阻尼效果，随着温度的降低，其阻尼特性变差；而低温阻尼材料在温度达到-10°C时阻尼效果最佳；常温阻尼材料在常温条件下中频部分阻尼性能最好；当低温阻尼材料与常温阻尼材料混合使用时，阻尼性能表现为宽温域，宽频带和高阻尼。低温和常温混合阻尼材料更适合高寒列车在不同季节下的运行条件。相关实测数据为高寒列车阻尼材料选材提供依据；同时，试验方法也为阻尼材料性能测试提供参考。%In low temperature environment the damping material performance of high-speed train will be deteriorated greatly, which will lead to the problem of vibration and noise of the train. In this paper, the change of property of the damping material used in high-speed train is investigated experimentally at the room temperature,-10° C and-25° C environments respectively. In the experiment, four panels with different sprayed damping structures are tested by the hammering method, and their natural frequencies, modals and damping ratios of the 57 orders below 850 Hz frequency are obtained. Then, the corresponding finite element analysis for the four panels without damping is done. And the results are compared with those of the experiments. The results show that the present damping material has good damping performance at the room temperature, but it becomes poor with the temperature dropping. The low-temperature damping material has a best performance at-10° C. The room- temperature damping material has a good performance at the room-temperature in intermediate frequency range. When using the room temperature damping material combined with the low temperature damping material, the panels show a high damping effect in a wide temperature range and a wide frequency band. So the mixture of the low temperature damping material and normal temperature damping material is more suitable to the high-speed trains operating in the area where the temperature changes drastically. The measured data provides a basis for the choice of the damping material for high-speed train, and the test method provides a reference for damping capacity test for damping materials.