重型柴油机试验台架振动特性分析与优化

Analysis and Optimization of Vibration Characteristics of Heavy-duty Diesel Engine Test Bench

以某型号重型柴油机振动噪声实验台架为研究对象,对实验台架的异常共振现象进行研究,优化重型柴油机实验台架的振动特性。通过有限元模态分析,计算了实验台架的模态与振型。对比不同优化方案的模态分析结果,发现在实验台架下连接钢槽水泥体能使实验台架发生强烈共振的频率显著提升,当钢槽水泥体厚度为80~500 mm时,共振频率提升126%~248%;将铁地板切割为两部分,试验台架发生共振的频率提升380%。轴心高度每降低50 mm,共振频率提升约1.8%。因此,增加铁地板厚度和将铁地板分为两部分,是避免试验台架在实验转速范围内发生异常共振的有效途径。

Taking a heavy-duty diesel engine vibration and noise test-bed as the research object,the abnormal resonance phenomenon of the test-bed is studied to optimize the vibration characteristics of the heavy-duty diesel engine test-bed.Through the finite element modal analysis,the modal and mode shapes of the test bench are calculated.Comparing the modal analysis results of different optimization schemes,it is found that the frequency of strong resonance of the test bench can be significantly increased by connecting the steel trough cement under the test bench.When the thickness of the steel trough cement is 80~500 mm,the resonance frequency can be increased by 126%~248%;By cutting the floor into two parts,the resonance frequency of the test bench can be increased by 380%;When the axis height decreases by 50 mm,the resonance frequency can be increased by about 1.8%.Therefore,increasing the thickness of the iron floor and dividing the iron floor into two parts are effective ways to avoid abnormal resonance of the test bench within the experimental rotational speed range.