倾角和压力对空气中微润管出流特性的影响

为探明倾角(微润管与水平面的夹角)和压力对空气中微润管出流特性的影响,确定微润管倾角和压力与比流量的关系,通过室内试验研究了不同铺设倾角(0°、30°、45°、60°、90°)及0°和90°倾角时不同压力水头条件下微润管的出流特性。结果表明:微润管出流规律符合达西定律,微润管比流量随压力水头的增大而增大,两者具有较好的线性关系;相同进水压力条件下,微润管比流量随倾角的增大而增大,与倾角正弦值呈线性关系,可将微润管倾角折算为等效水头;据此提出了包括倾角和压力的微润管比流量计算公式。研究成果为微润灌溉工程规划、设计提供基础依据。

Effect of dip angle and pressure head on flow characteristics of moistube in the air

In order to find out the effect of dip angle (the angle between moistube and horizontal plane) and pressure on the flow of moistube in the air, and to determine the relationship between moistube dip angle, pressure and the specific discharge, the discharging characteristics of moistube was studied through laboratory test under conditions of different laying angles (0°, 30°, 45°, 60°, and 90°) and different pressure head of 0° and 90°. The results indicate that the flow of moistube accords with Darcy''s law, the specific discharge of moistube increases with the increase of pressure head and there are good linear relationship between them. Under the same water pressure head, the specific discharge of moistube increases with the increase of the angle and has a linear relationship with the inclination of sine, while the moistube angle can be converted into equivalent head.Thecalculation formula of moistube specific discharge including angle and pressure head is put forward. The research results can provide basis for the planning and design of the micro embellish irrigation works.