what is the name of Nuh's son

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

If you mean the son of Nooh (Noah) who did not ride the ship, and was among the drowned, and whose story is mentioned in the Quran, then there are different narrations about him. Ibn Katheer said in his Tafseer (Interpretation of the Quran): "This is the fourth son whose name was Yaam; and he was a disbeliever." Al-Qurtubi said, “Allaah’s Saying (which means): {and Noah called to his son}[Quran 11:42]: It was said that he was a disbeliever and his name is Kan`aan, or Yaam according to another saying."

Allaah Knows best.