Lewis said: "I am delighted to accept this position. We will now positively harness the energy that has been generated by the recent debate and together take Women's Six Nations rugby forward."
Meanwhile, Fiona Hayes, a member of the Ireland Women's Grand Slam-winning squad this year, will be at Thomond Park this Saturday as Munster take on Leinster in their big RaboDirect PRO12 derby.
Cork native Fiona will be joined by Ireland Women's head coach Philip Doyle to present the Six Nations trophy to supporters and conduct a half-time interview live on the big screen.