Is 流 a mountain-water painting?About 流:
Its first part is called ‘three-drop-water’ in Chinese; The top of its right component is changed-form of 云（clouds) and the bottom one should comes from 川 （river) which two sides symbol the banks of the river and the middle-vertical-stroke represents the water-current!
So, look at the whole word: Three streams flows; Over the head the clouds are floating in the sky and it seems that it is raining hard; The current of the river is so strong that the banks are going to be broken and the water would probably become flood!
流（liu) means ‘current’ or ‘running current’ or ‘flowing’. ---------------Chinese people often use simple drawing to express some object. Is it funny？I hope you enjoy my explaining!
(You may also take the 川-like thing as a changed form of 水(water）. Why? The ancient form of 水 looks like cloth-like waterfall. One Chinese described cataract in this way: The great waterfall comes down from the top of the high cliff of the mountain, it seems that as if it had flied here from the heaven!