Viscosity is the key feature of liquids. A high viscosity value makes them behave stiff, whereas a low value relates to the smooth flow of water.

In this tutorial we simulate liquids with different velocity settings. And we exchange the water shader with a gold shader.

Here's the Wikipedia article about viscosity:

https://en.wikipedia.org/wiki/Viscosity

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And here are some renderings of this kind of approach in my blog:

http://www.maxschoenherr.de/clock/bif...

And here I animate water flowing along a curve:    • Maya: Water Along a Curve [Bifröst]