The most reasonable method is that at least one of the author's subordinate units has purchased genuine FLUENT, so it doesn't matter whether your result is pirated FLUENT or genuine FLUENT simulation.

If all the author units have not purchased FLUENT, then if these units are not blacklisted by FLUENT, even if the paper mentions FLUENT, don't worry too much, and no one will pursue it. Of course, it's hard to say when someone investigates. It's just that many of our articles are published in this way, and they are all pirated and smooth. I've never heard of anyone having a problem. As far as I know, some units are blacklisted by Ni, but their papers will still say that Ni collected the data, and it is no problem to win EI.

If you really dare not write, you can only say that your method is numerical simulation, not to mention any commercial software. The calculation method needs to be more detailed, such as finite element or finite volume, turbulence model, discrete scheme and so on. And it is best to explain clearly.

I hope it helps you.