CAJ | 학술논문

为研究粗细颗粒间相互作用对非均匀沙输移的影响，采用推移质动态采集、图像识别和多普勒测速技术，实现了瞬时输沙量、颗粒组成与近壁脉动流速的实时同步监测。针对双峰型非均匀沙进行了211组推移质系列水槽试验，分析表明：推移质输移量与粗沙拣选度的随机波动与紊动猝发引起的流速脉动具有响应关系；推移质中细粒基本保持持续输移，而粗粒输移则具阵发性，并遵循促发、触发与失怙3种模式；颗粒组成结构对3种模式的实施过程有重要影响；它制约着泥沙中细粒对粗粒的激励、碰撞和解怙强度，使得推移质总沙、细沙和粗沙输移率随床沙组成的改变各自呈现出不同的变化规律；水流强度一定时，随床沙粗细比的减小，输沙率呈驼峰型曲线变化；只有适宜的粗细颗粒搭配（ηc）才能使非均匀推移质输沙率达到峰值，且大于该床沙组成中任一均匀沙的输沙率。
위연구조세과립간상호작용대비균균사수이적영향，채용추이질동태채집、도상식별화다보륵측속기술，실현료순시수사량、과립조성여근벽맥동류속적실시동보감측。침대쌍봉형비균균사진행료211조추이질계렬수조시험，분석표명：추이질수이량여조사간선도적수궤파동여문동졸발인기적류속맥동구유향응관계；추이질중세립기본보지지속수이，이조립수이칙구진발성，병준순촉발、촉발여실호3충모식；과립조성결구대3충모식적실시과정유중요영향；타제약착니사중세립대조립적격려、팽당화해호강도，사득추이질총사、세사화조사수이솔수상사조성적개변각자정현출불동적변화규률；수류강도일정시，수상사조세비적감소，수사솔정타봉형곡선변화；지유괄의적조세과립탑배（ηc）재능사비균균추이질수사솔체도봉치，차대우해상사조성중임일균균사적수사솔。
In order to study the impacts of the interactions between the coarse and fine particles on the non-uniform sediment transport, the real time simultaneous monitoring of the sediment delivery amount, grain composition and the fluctuating velocity near bed have been realized,based on the technologies of in?stantaneous bed load acquisition, image identification and Doppler velocity measurement, etc. Aimed at the non-uniform sediment with bimodal pattern, 211 cases experiments on bed load transport have been carried out under series flume conditions. The analysis indicates that the random fluctuation of the bed load trans?port quantity and selection degree of the coarse particles have some response relations with the velocity fluc?tuation caused by the turbulence burst near the bed. The fine particles in the bed load mostly remain con?tinuously transport in a process, however, the transport of the coarse particles is always paroxysmal, abid?ing by three modes:priming,triggering and breaking. The structure of particles composition plays an impor?tant role in the enforcement of the three models. It restricts the effect intensity of exciting, colliding and breaking of the fine particles on the coarse particles, which results that the transport rates of the total, fine and coarse show different variation trends respectively with the changing of the bed material composi?tion. At a certain flow intensity, the transport rate presents a hump curve with the decrease of the thick?ness ratio of bed load. Only if the ratio is appropriate,may the transport rate of the non-uniform bed load reach the peak, which is higher than either transport rates of the uniform coarse or fine sediment in this non-uniform sediment. Such cognition may give a significance reference for the improvement of non-uniform sediment transport theory.