Effect of suction nozzle structure on reverse circulation performance of down-the-hole hammer drill bit

This paper aims to disclose the effect of suction nozzle structure on the RC suction capacity of DTH drill bit. For this purpose, three different types of suction nozzles were developed for the DTH drill bit. Then, the CFD software was adopted to simulate the fluid movement in a hole and the DTH drill bit. The results show that type three ranked first in terms of RC suction capacity, while type two came at the bottom. Then, the entrainment ratio was introduced to quantify the RC capacity. The results show that the RC capacity of type three is about 6 times of that of the other two types of nozzles. Our research opens up a new direction for future engineering practices.