共查询到15条相似文献,搜索用时 171 毫秒
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井下用锚杆钻车风机除尘系统服役一定周期后噪声恶化,为找出噪声恶化原因,将消声器进行拆解,发现消声器内部穿孔管部分堵塞,多孔吸声材料被煤尘污染。构建消声器声学有限元模型,计算穿孔管被煤尘完全堵塞、部分堵塞及正常使用下消声器传声损失,并初步探讨吸声材料污染对消声器传声损失的影响。仿真结果表明穿孔管堵塞是造成消声器消声性能下降及除尘系统噪声恶化的主要原因,说明要想保证除尘系统噪声水平需要提高除尘系统除尘能力,避免消声器污染。 相似文献
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介绍了消声器声学及流场仿真的理论及方法,针对某工程车辆排气噪声贡献大的特点,对其消声器进行了声场仿真,根据仿真结果对消声器进行了结构优化,通过计算流体力学(CFD)的方法对优化前后的消声器进行了流场仿真,仿真及试验结果显示,改进后消声器改善了消声性能和空气动力性能。 相似文献
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分析液压系统中压力损失产生的原因,介绍液压油在圆管呈层流和紊流2种流动状态时,沿程压力损失的计算公式,对液压管道、液压附件等局部阻力系数及压力损失计算方法进行探讨;提出减少液压系统中压力损失的相关方法。 相似文献
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在煤矿企业高压输供电过程中,电能传送和电磁能量转换都是通过电流实现的,电流通过导线或电气设备时会产生损耗。线损是电能在传输过程中所产生的有功、无功电能和电压损失的简称,线损管理是供电线路的一项重要工作,线损率是电力系统规划设计、生产运行、经营管理和企业经济效益水平的综合体现。文章通过对煤炭企业供电网络负荷进行分析整理,针对影响煤矿110kV供电网线损的多种因素,对煤炭企业高压供电网络的理论线损进行了分析与计算,并对煤矿企业110kV供电网的降损措施进行探讨。 相似文献
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Dr. Reina Hashimoto Gregor Mori Muhammad Yasir Uwe Tröger Helmut Wieser 《BHM Berg- und Hüttenm?nnische Monatshefte》2013,158(9):377-383
The chemical composition of condensates recovered from a test car was systematically analysed in this study. It was found that most condensates contain a higher concentration of chloride than that of sulphate. In order to understand the effect of sulphate on the pitting behaviour of 436SS and to predict whether pitting will occur in these condensates, pitting potentials were determined in a 0.2M sulphate solution with varying chloride concentration by using the potentiodynamic cyclic polarization curve method. The results demonstrate that sulphate prevents pitting initiation of 436SS when the concentration of sulphate is higher than that of chloride. However, no inhibitory effect of sulphate was observed when the sulphate concentration is lower than the chloride concentration. As the condensate recovered from the muffler contains more chloride than sulphate, the muffler is most likely suffering from pitting. This was confirmed by the microscopic observation of the corroded muffler from the test car. 相似文献