Variations in pressure with and without aeration in cavitation region are measured and the compressible characteristics of pressure waveforms and relation between mach number and compression ratio are analyzed ; the time - averaged pressure profiles of different air concentration in cavitation erosion region are measured , the variations of the pressure with air concentration and effects of back pressure on cavitation erosion are analyzed ; the relations between least air concentration to prevent cavitation erosion and flow velocity are proposed ; the cavitation numbers with and without aeration in cavitation region are compared 实测了空化区掺气前后压力的变化，分析了压力波形的可压缩流特征以及马赫数与压缩比的关系；实测了空蚀区不同掺气浓度的时均压力分布，分析了压力随掺气浓度的变化及背压对空蚀的影响；提出减免空蚀的最低掺气浓度与流速的关系，比较了掺气前后水流的空化数。
The surface material is liable to erosion wear with high - velocity sediment - laden flow , hi this paper , sand wear mechanisms are discussed and some effects of significant flow factors on material wear are analyzed ; the possibility of preventing erosion wear with aeration is proposed ; based on test data , the formula for calculating the concrete material wall surface wear rate is derived . it is indicated that the wear rate is related to the air concentration , the strength of material , the flow velocity and the sediment content . it is shown that wear rate can be reduced with the help of flow aeration 分析了空蚀与磨蚀的不同物理特征；探讨了沙粒磨蚀机理，提出了影响磨蚀vi河海大学博士学位论文一的因素；研究了掺气抗磨的可能性：建立了混凝土材料壁面磨蚀率的计算公式；说明含沙水流对固壁材料的磨蚀率随掺气浓度、材料强度的增大而减小，随水流流速、含沙量的提高而增大；利用掺气可有效地降低过流表面的泥沙磨蚀率。
In order to increase the energy dissipation of stepped spillway at iarge unit discharge , the integhty dissipater of aerated splitter pier and steppe characteristics is studied . because of verticaj diffhaion now by aerated splitter and impachng steppe 3 by drop flow , the air concentration and the energy dissipation efficiency are greatly increased ; the potentiality of cavitations is decrease . in special at large unit discharge , this effect is more obvious 掺气分流墩的增加，明显地改善了阶梯面上的压强分布，消除或减小了阶梯凹角内和立面上部的负压；由于掺气分流墩使水流纵向扩散以及挑流落下后在阶梯上的撞击，使水流的掺气浓度和消能率都得到较大的提高，降低了阶梯面空蚀的可能性，特别是在大单宽流量时，这种效果更为明显。
Based on simulation results which were satisfied , the effect of bubble diameter on entrainment concentration forcast result was analyzed . the bubble moving rule was found which includs the bubble is escaping upwards along the way , the diameter of the bubble is bigger , the velocity upwards is larger and the bladder remaining near channel bottom is smaller . to make best use of the function of the aerator , the demands of enough air entrainment quantity and suitable air bubble diameter are needed to be satisfied 根据计算结果，对水气两相流中气泡尺寸对掺气浓度预测结果的影响进行了分析，得到沿程气泡不断上逸，气泡粒径越大，其上逸速度越大，则留在渠底附近的气泡越少的气泡运动规律，提出了掺气槽的设计，除满足掺气量外还应满足掺气粒径要求的工程建议。
United with visual c + + language which face to object , a software is exploited which have functions like gray transform , image improve , bubble identify , void fraction calculation , which show the strongpoint of object - facing programming . in order to validate the reliability and practicability of the image technique in measurement of bubble void fraction , a test aiming at water - gas field is done 为验证本文给出的掺气浓度图像处理方法的可靠性和实用性，作者采用图像处理技术对掺气浓度场进行实测研究，研究结果表明:文中实测计算出的掺气浓度值是可靠的，基本上能反映真实的掺气浓度情况，这表明本文提出的方法具有实际应用价值。
