Using slit outlet, the critical height of vortexsink is substantially lower than that of the round outlet used when the area of outlet and flow are equal.
采用缝隙式出流口时产生漩涡的临界高度比采用同面积的圆形出流口时的低得多。
2
A sink brims with water.You pull the plug.The water stirs.A vortex materializes.
满满一盥洗槽的水，当你拔去水槽的塞子，水就会开始搅动。
3
In this paper, the effect of compression does not be treated with PrandtI-Glauert's transformation, bat directly treated with compressible source (sink) and vortex.