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本文在曲率缓变型反弧段水流时均特性研究的基础上，进一步使用二维激光测速系统对其紊动特性进行探讨，通过试验测得反弧段时均流速分布，流向和法向脉动流速的各种特征值；应用离心不稳定性理论分析了反弧水流特性，阐明沿程断面流速分布在反弧前半部趋于瘦弱，后半部趋于丰满的原因，并说明离心不稳定性作用导致反弧水流的混掺加剧；论证了壁面切应力和紊流强度在反弧后半段逐渐增加的原因；通过试验发现离心不稳定性效应的滞后现象．本文还就时均能量平衡、紊动能量平衡进行了较详细的分析．
In this paper, based on the study of the mean-time characteristics of the curvilinearly curved reverse arc water flow, the two-dimensional laser velocity measurement system is used to investigate its turbulent characteristics. The mean velocity distribution, flow direction and normalized pulsation velocity The characteristics of the anti-arc flow were analyzed by using the theory of centrifugal instability. The reason why the flow velocity distribution in the cross section was lean towards the first half of anti-arc and the latter half tended to be full, and explained the instability of centrifugation Which leads to the aggravating mixing of anti-arc water flow. The reason why the wall shear stress and turbulence intensity gradually increase in the latter half of arc-reverse flow is demonstrated. The lag phenomenon of centrifugal instability effect is found through experiments. In this paper, the energy balance and the energy balance of turbulence are also analyzed in detail.