定位格架与子通道压力损失预测模型研究

摘要

定位格架与子通道压力损失的准确预测对定位格架和压紧系统设计以及临界热流密度关系式开发有着至关重要的影响.本文通过对典型定位格架结构识别,研究了典型定位格架子通道划分依据,重点研究了定位格架压力损失与子通道压力损失之间的关系以及子通道内各设计特征,包括不同设计的弹簧、刚凸、搅混翼、导向翼、条带等引起的压力损失特点.通过对子通道内各设计特征进行合理简化与抽象,以经典水力学阻力结果为基础,等效为圆管内具有一定倾角的平板,从而建立了子通道压力损失预测模型,进而建立了定位格架压力损失预测模型.计算结果显示模型能准确预测试验值.%Accurately predicting pressure loss of spacer grids and sub-channels is critical for fuel assembly spacer grids and holding system design and for developing critical heat flux (CHF) correlation .The present study distinguished different types of sub-channels in a typical mixing spacer grid , and focused on the investigation of the relationship between spacer grids pressure loss and the sub-channels pressure loss .Different design features were considered ,including springs ,dimples ,mixing vanes and guide tabs etc . Based on classic hydraulic resistance results , all design features were hydraulically equivalent to flat plate with an angle in a circular tube .Models of predicting pressure loss of spacer grids and sub-channels were established .It is found that the prediction results agree with the experimental results very well .