The nccessity and urgency of PDCbit downhole folw field testing are demonstrated according to the character of PDC bit structure,principle of rock fracturing and circumstances of using in drill sites.

• 根据PDC钻头的结构特点、破岩原理及现场使用情况，阐明了进行PDC钻头井底流场试验研究的必要性和迫切性。