基于实验数据的吊篮表面脉动压力分析

基于堆内构件缩比模型流致振动实验实测得到的吊篮表面脉动压力数据,分析了吊篮表面不同位置脉动压力功率谱密度的分布特征,并对脉动压力功率谱密度的相关性进行分析得到相关长度的特性。结果表明,吊篮表面的脉动压力功率谱密度随频率的增大快速减小然后趋于平缓,是一种频率成份十分丰富的宽带衰减谱,在吊篮同一高度区域的脉动压力功率谱密度基本相同,不同高度区域的脉动压力功率谱密度的能量差别较大;脉动压力功率谱密度的相关长度随频率递增而急剧减小然后趋于常值;吊篮流致振动响应对脉动压力功率谱密度的影响较小,将吊篮流致振动简化为弱耦合问题是合理的。 

Analysis for Fluid Pressure Fluctuation of Core Barrel Surface Based on Experimental Data

Based on the fluctuating pressure data obtained in the flow- induced vibration test of reactor pressure vessel internals scale model, the distribution characteristics of fluctuating pressure power spectral density are analyzed at different positions on the core barrel surface, and the correlation length characteristics of fluctuating pressure power spectral density are obtained based on the correlation analysis. The power spectrum density of the fluctuating pressure on the core barrel surface is broadband attenuation spectrum with a very rich frequency andecreases quickly with the increasing of the frequency and then tends to be gentle; The fluctuating pressure power spectral density is basically the same in the region located at the same height on the core barrel, but the differences of the PSD (power spectral density) are obvious between the regions at different heights. The correlation length of the fluctuating pressure power spectrum density decreases sharply with the increasing frequency and then tends to be constant. The flow-induced vibration response of the core barrel has little effect on the fluctuating pressure power spectral density and it is reasonable to simplify the flow-induced vibration of the core barrel into the weak coupling problem.