Simulation and Analysis of the Cutting and Drilling Process of the Human Skull Bone with Water Jet Process Using Finite Element ABAQUS Software.

Behnaz ali Jani¹ Niloufar Kazemi²

1) Department of Biomedical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
2) Department of Biomedical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran

Publication : International Congress on Science, engineering & New Technologies(secongress.com/1st)
Abstract :
The bone drilling process is the most important process in orthopedic surgery and fracture treatment, and it is also widely used in dentistry and bone sampling. In simulating the impact of water jet on bone tissue, we are dealing with two-phase liquid-gas flow. For this reason, the fluid volume method has been used for two-phase flow. Also, in this research, the heat transfer in the impact of the water jet on the surface of the hemisphere has been investigated. According to the results obtained for a constant nozzle diameter, the distribution of pressure coefficient and friction coefficient on the collision surface depends on the distance of the nozzle from the surface. The pressure increases as the distance of the nozzle from the surface decreases at the still point. From the analysis of the Nusselt number distribution with constant diameter and changes in the distance of the nozzle from the surface, it was shown that the local Nusselt number decreases from the maximum value at the still point along the r/d radius, and as the distance of the nozzle from the impact surface increases, the maximum Nusselt at the still point, decreases. Also, for a fixed distance from the nozzle to the collision surface, the distribution of pressure coefficient and friction coefficient on the collision surface depends on the diameter of the nozzle from the surface. The pressure increases with the increase in the diameter of the nozzle at the stagnation point. Also, the speed changes for the hemisphere geometry show that a 20% change in the jet speed did not have a significant effect on the pressure and friction coefficients, but the speed increase caused a 44.5% increase in the Nusselt number. Using the ABAQUS software, which is a software based on the finite element method, a hemisphere segment that can be a simple model of the human skull has been modeled and by applying real characteristics and coefficients, such as Poisson s ratio and Young s modulus, for the bone surface in the model, to A section of the hemisphere has been drilled into the bone material. As a result, the drilling contour of the bone surface has been shown with Tresca and Von Mises criteria, as well as the comparison of the maximum applied stresses in different criteria, and it was concluded that with a speed of 232 m/s and a distance of the nozzle from the surface of 0.5 mm and a nozzle diameter of 1 mm, which is considered in this research taken, a proper drilling can be done
Keywords : Water Jet Bone Drilling Simulation Finite Element ABAQUS Software Johnson Cook Criterion