مطالعهی آزمایشگاهی قدرت جریان ثانویه و مقدار ورتیسیتی در قوس ۹۰ درجه با آبشکنT شکل منفرد

Abstract

This paper deals with the results of experiments on strength of the secondary flow and vorticity in a channel bent with and wiuthout a spur dike located at section 75o of the bend. Experiments were conducted in a channel with a 90o bend. The results of experiments with spur dike for two cases of flat bed and scoured bed are compared. The three-dimensional Acoustic Doppler Velocimeter (ADV) was used for measuring the flow field.The comparison of three dimensional components of velocity was made in different sections and strength of the secondary flow and vorticity along the bend were analyzed.The results show that in the bend without the spur dike, The strength of the secondary flow and vorticity were maximum at about section 40 degree of the bend. While in the bend with the spur dike, maximum strength of the secondary flow and vorticity were maximum at about section 73.75 degree of the bend.The variations of secondary flow, vorticity and vortices in diiferent sections of the bend were also addressed in this paper.