Not in the sense you probably mean, but I have performed three or four analyses when I worked at an engineering firm (entertainment - structural, mechanical) in F#. One involved an FSI system (Fluid-Solid Interaction using Project Chronos in C++) that I used F# for the mathy parts before the simulation. I also used F# to munge failure data and perform a Weibul analysis and generate a report for ride equipment. I have not used F# at all for web stuff. I typically reach for Mathematica (tried Julia, love it, but Mathematica's all-in-one notebook with curated data is hard to beat when you are doing something ecelctic and don't want to lose the flow of trying to pull in a data source or search for a library). I wish F# had more presence in the scientific community. It's very simple compared with Haskell, less verbose than C#, and it has the entire .Net ecosystem to draw on.