Ansys use the command /units
USER — User-defined system (default).
SI — International system (SI or MKS; m, kg, s, K).
CGS — CGS system (cm, g, s, °C).
MPA — MPA system (mm, Mg, s, °C).
BFT — British system using feet (ft, slug, s, °F).
BIN — British system using inches (in, lbm...