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对水面舰艇纵向轴系游动端支座间隙设计的深化研究 总被引:5,自引:2,他引:3
通过系统的分析研究表明,水面舰艇中垂及中拱弯曲变形对纵向轴系游动端支座间隙有一定的影响,尤其当纵向轴系被固定在上甲板或舰底时,这种影响会达到不容忽视的地步。本文提出一项新的纵向轴系游动端支座合理间隙设计计算公式。由于该公式较客观地计及耻舰艇中垂及中拱弯曲变形对纵向轴系游动端支座间隙的影响,因此,用该公式计算,可使水面舰艇纵向轴系游动端支座间隙设计变得更安全、更切合实际。 相似文献
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本文提出一项新的纵向轴系游动端支座合理间隙设计计算公式。该公式较客观他计及了舰艇中垂及中拱弯曲变形对纵向轴系游动端支座间隙的影响,因此,按该公式计算,可使水面舰艇纵向轴系游动端支座间隙设计变得更安全、更切合实际。 相似文献
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为了使船舶纵向轴系游动端支座游隙设计更切合实际,本文提出一项将船体中垂或中拱弯曲变形影响包括在内的船舶纵向轴系游动端支承游隙设计公式,利用该公式及有关已知参数,船舶机械工程技术人员很容易直接求得船舶纵向轴系游动端支座游隙的合理尺寸。 相似文献
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船体中垂及中拱弯曲变形对纵向轴系游动端支承游隙所造成的影响是不可忽视的。本文提出了一项形式十分简单的游隙设计公式,使船舶纵向轴系游动端支承游隙设计更切合实际。 相似文献
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减小船舶轴系纵向振动的动力减振器参数优化 总被引:1,自引:0,他引:1
在船舶轴系中安装动力减振器是减小轴系纵向振动的有效方法,而对动力减振器参数优化的研究是有效控制振动的关键之一。基于达朗伯原理建立船舶轴系纵向振动数学模型,导出动力减振器响应位移的动力放大系数解析式,运用动力谐调消振理论求解最优固有频率比和最优阻尼比。然后针对特定频带内动力减振器的参数优化,以固有频率比与阻尼比为设计变量,选择两种目标函数,采用最大值最小化问题的直接搜寻算法得到动力减振器参数的最优值。比较和分析了各种计算方法得到的结果,并研究动力减振器各参数对船舶轴系纵向振动影响,为轴系纵向振动控制及动力减振器的设计提供理论了依据。 相似文献
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针对轴系纵向振动引起的船舶尾部振动噪声问题,提出基于主动推力平衡原理的轴系纵向减振方法,设计了轴系纵向减振结构,通过试验研究了该结构的刚度特性,并对比分析了应用纵向减振结构前后轴系纵向振动特性。结果表明,提出的基于主动推力平衡原理轴系纵向减振方法,可有效化解减振结构低动刚度和高静刚度之间的矛盾,有利于桨轴系统纵向振动控制向低频范围扩展;应用基于主动推力平衡原理的纵向减振结构后,轴系纵向振动控制效果明显。 相似文献
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介绍了我国港口资源的整合现状,指出港口整合可以提升港口的形象和地位,也为区域经济和城市的发展注入强大的动力。最后指出在港口资源整合中要避免的几个问题。 相似文献
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广州集装箱码头的轮胎式场桥小车制动器使用10多年后,出现了许多问题,故进行了改造.分析了轮胎式集装箱龙门起重机小车制动器的主要故障现象,提出了改造方案,并加以实施. 相似文献
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本文对现有的选定球面轴承的三种工程方法进行了分析比较.引入了“合力系数”,并给出了合力方向上投影面积的精确解. 相似文献
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分析柴油机故障中常见的机体裂纹故障原因,认为由于设计缺陷和管理及操作不当,易造成船舶柴油机缸体上的裂纹多发生在气缸套凸肩处。如不及时处理这些裂纹和故障,就会造成缸套的裂纹直至出现缸套漏水等严重后果,针对NANTAIQUEEN轮柴油机对该类型故障的检修提出具体措施。 相似文献
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The hydrophysical and hydrochemical structure of the Sea of Azov, with developed bottom anoxia, was studied during the RV “Akvanavt” cruise from July 31 to August 03, 2001. The anoxic zone with a thickness from 0.5 to 4 m above the bottom was found in all deep regions of the Sea. Concentrations of hydrochemical parameters were similar to the pronounced anoxic conditions (about 90 mmol m− 3 of hydrogen sulfide, 17 mmol m− 3 of ammonia, 6 mmol m− 3 of phosphate, 7 mmol m− 3 of total manganese). The hydrophysical structure was characterized by the uniform distribution of temperature in the upper 6–7 m mixed layer (UML). Below this a thin (0.4–0.8 m) thermocline layer was observed, just above the anoxic waters. Formation of this phenomenon was connected with that summer weather conditions. Intensive rains led to increased influx of river waters in June. That resulted in large input of allochtonous organic matter (OM) and inorganic nutrients; the latter were consumed on the additional autochthonous organic matter production. In July the weather was characterized by a significant rise in the daily averaged air temperature and large oscillations of temperature during the day. In this period a wind of constant direction was absent, but wind bursts were observed. The completed analyses showed that the formation of such a structure could be connected with the following factors: (i) positive growth trends of the daily averaged temperature and the daily oscillations of temperature, (ii) presence of wind bursts. The joint action of these factors resulted in the formation of the UML. The amplitude of wind bursts determined the depth of UML, and the value of trend determined the value of the temperature change in the thermocline. An initial presence of bottom halocline (caused by the Black Sea water influx to the bottom of the Sea of Azov) prevented the heating of the bottom layer and therefore led to an increase of vertical gradient of temperature in the thermocline. The spatial distribution of the turbulent exchange coefficient confirmed the existence of a “stagnation” area located above the anoxia zone, which is also, apparently, the reason for its occurrence. 相似文献
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