不同断面形态河槽阻力特性试验

Experimental study on resistance characteristics of flumes with different cross-section shapes

阻力相似是河工模型关键问题之一。本文通过水槽试验分别对偏V形断面和矩形断面明渠加糙后的阻力特性进行对比研究。研究结果表明:在阻力平方区,偏V形水槽加糙后随雷诺数增加阻力变化很小,对于矩形水槽加糙后随着雷诺数增加阻力有略微减小的趋势;当雷诺数为10000时,矩形断面加糙后其阻力明显大于偏V形断面加糙后的阻力,随着雷诺数增大两者阻力趋于相同值。

Resistance similarity is a key principle in river models. To simulate resistance, the artificial roughening method is employed. Experiments are performed to compare the resistance characteristics of a V-shaped flume and a rectangular flume, both with Y-shaped materials to enhance their roughness. Research results show that, in the turbulent regions, the resistance ccefficient of the V-shaped flume changes very little with the Reynolds number, but that of the rectangular flume appreciably decreases with the Reynolds number. When the Reynolds number reaches 10000, the resistance coefficient of the rectangular flume is larger than that of the V-shaped flume. As the Reynolds number increases, the resistance coefficients of both types of flumes trend to have equivalent values.