How to optimize the width of 50 ou microstrip in HFSS or CST

How can I optimize the width of 50 Ω microstrip in HFSS or CST?That is, How can I get the best width when the impedance of the microstrip equals to 50 by simulation in HFSS or CST?
Thanks in advance!

I don't see why you want to optimize the witdth of a 50ohm microstrip. There are empirical models, free tools like "line call", etc. So the 50 ohm width is known, so what you need to optimize?

Yes, if you desing 50Ohm ms line with (semi)empirical utils like TXLINE, EM simulation in HFSS or CST should fit - if not, your model is probably bad!
I use TXLINEs to design the ms lines and it's enough accurate.

Hi burton,
I think you do not need to put extra effort just to design a 50 ohm line, because there are many free tools which you could get the width of the 50 ohm line just by entering the specifications that you need.