通风机消声器性能研究和选配安装

介绍了通风机噪声产生的机理及主要噪声源部位 ,根据噪声传播的衰减规律及大量消声器的试验总结资料 ,提出了常用消声器的选配原则和安装方式。

爆轰载荷下三层药型罩射流成型影响研究

针对普通药型罩侵彻能力不足的问题,提出了一种新型三层药型罩,利用AUTODYN软件模拟三层药型罩射流成型过程,研究三层药型罩3种材料、不同厚度比对射流性能的影响。研究结果表明:三层药型罩外、中、内罩材料分别为铝、铜、镍时,射流性能最好;在此装药结构上增加外罩厚度可有效提升射流的速度、有效长度和总能量,提高射流性能;在所设计的10组不同厚度比方案中,三层药型罩最优厚度比为4/1/1,该结构下的射流比单层铜药型罩的射流头部速度提升15.91%,有效长度增加15.28%,总能量提高26.61%;与双层铝-铜药型罩相比,射流头部速度提升3.71%,有效长度增加2.79%,总能量提高10.24%。

Experimental Study on Noise Reduction of Punch Press

To reduce the noise of punch press during the punching process, the polyurethane elastomer is used as the damping material. The experiments of reducing noise were made by means of adding the polyurethane elastomer at different positions of 100 kN and 1 000 kN punch press. The better effect of reducing the noise was obtained. With the research and analysis of a large number of test data, the 'equivalent damping hypothesis' is put forward. The hypothesis makes the experiment of reducing noise be more simple and cost effective. This method would be exploited in area of vibration control and reducing noise.