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本研究通过普通螺旋桨(无侧斜)和大侧斜螺旋桨在空泡水洞两个特定流场(对称非均匀流场和不对称非均匀流场)中诱导的脉动压力试验测量,探讨其不同的脉动压力特性和侧针的减振效果;介绍了为测量脉动压力而建立的传感器和数据采集处理系统。这一根据高速采集储存数据、慢速传送微机处理思想建立起来的Molti-Function系统,有别于通常采用的由高速处理机和磁带记录机组成的脉动压力数据采集处理系统,具有数据采样速度快,无信号失真等优点。本研究发现,大侧斜桨具有降低螺旋桨空化诱导的脉动压力幅值作用,但这一作用的大小与空化数和流场特徵有关;无论是普通桨还是大側斜桨,在不均匀流场中诱导的脉动压力均具如下特徵,即与一阶叶频谐调分量相比,在较大空化数情况,二阶以上叶频谐调分量明显丰富,而在较小空化数情况,则明显变小。本研究认为,在应用简化网格模拟得到的不均匀流场中进行螺旋桨脉动压力测量的比较试验,可克服模拟流场差异带来的测量结果误差,有助于提高实验室的脉动压力测试技术水平。
In this study, the pulsating pressure test induced in the two specific flow fields (symmetric non-uniform flow field and asymmetric non-uniform flow field) of ordinary propeller (no side slope) and large side inclined propeller in hollow cavity was used to investigate the difference Of the pulsating pressure characteristics and side needle damping effect; introduced to measure the pulsating pressure and the establishment of the sensor and data acquisition and processing system. The Molti-Function system, which is based on high-speed acquisition and storage of data and slow transmission of microcomputer processing, is different from the commonly used pulsating pressure data acquisition and processing system which is composed of a high-speed processor and a tape recorder, and has the advantages of fast data sampling speed , No signal distortion and so on. In this study, we found that the large-side inclined propeller has the effect of reducing the amplitude of the pulsating pressure induced by propeller cavitation. However, the magnitude of this effect is related to the number of cavitations and the characteristics of the flow field. In both the ordinary propeller and the large propeller, The pulsating pressure induced in the flow field has the following characteristics. Compared with the first-order harmonic component, the larger the cavitation number is, the second harmonic component is obviously enriched. In the case of small cavitation number, Obviously smaller. In this study, the comparative experiment of pulsating pressure measurement of propeller in non-uniform flow field using simplified grid simulation can overcome the error of measurement results caused by the difference of simulation flow field, and help to improve the laboratory pulsating pressure testing technology Level.