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微坡旋转发电机对冲水喷气推进器性能的影响
Liu Chen1, Xiangqian Ma1, Ren Dai2
1College of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China.
Scientific reports
|August 25, 2025
概括
微旋发电机通过减少流量分离来增强船体入口. 这种被动的流量控制提高了喷水推进效率,并降低了高速的振动和噪声.
科学领域:
- 流体动力学
- 海军建筑
- 听力学
背景情况:
- 在船体入口的流量分离,特别是在低入口速度 (IVR) 时,降低了喷水推进性能.
- 在特定的操作条件下,现有的流量控制方法可能很复杂或效率较低.
研究的目的:
- 调查微旋发电机 (MRVG) 在减轻流量分离和提高冲水喷气推进系统的性能方面的有效性.
- 确定MRVG设计的最佳参数,并评估它们对流量均性,压力回收和推进效率的影响.
主要方法:
- 使用数值模拟来分析MRVG参数 (高度,角,边长,跨度间距) 对流量特征的影响.
- 进行了参数查以确定最佳的MRVG配置.
- 评估了性能指标,包括流量均性,旋转,总压力扭曲,推力,推进效率,压力脉冲和激发力.
主要成果:
- 最佳的MRVG高度是上游边界层厚度的20-40%;角和长度显示无关紧要的影响.
- 在0.5的IVR下,优化的MRVG减少了41.5%的流量不均,74.0%的旋转,61.6%的总压力扭曲,同时增加了8.4%的总压力恢复.
- 推力提高了2.86%,推进效率提高了1.60%,推进器压力脉冲幅度降低了40.86%.
结论:
- MRVG是一种有价值的被动流量控制技术,用于提高冲水喷气推进系统的整体性能.
- 使用MRVG可以显著降低水喷气推进系统在高速巡航时的振动和噪声.
- 对于提高水力动力效率和运行稳定性,MRVG提供了一个简单而有效的解决方案.
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