Virtual Chip Test and Washer Simulation for Machining Chip Cleanliness Management Using Particle-Based CFD

Metal cutting/machining is a widely used manufacturing process for producing high-precision parts at a low cost and with high throughput. In the automotive industry, engine components such as cylinder heads or engine blocks are all manufactured using such processes. Despite its cost benefits, manufacturers often face the problem of machining chips and cutting oil residue remaining on the finished surface or falling into the internal cavities after machining operations, and these wastes can be very difficult to clean. While part cleaning/washing equipment suppliers often claim that their washers have superior performance, determining the washing efficiency is challenging without means to visualize the water flow. In this paper, a virtual engineering methodology using particle-based CFD is developed to address the issue of metal chip cleanliness resulting from engine component machining operations. This methodology comprises two simulation methods. The first is the virtual chip test, which can track the movement of machining chips within internal cavities and tunnels of a machined part, such as the water jackets and oil galleries of a cylinder head, and the simulation results can be used to predict chip clogging locations and severity. Next, the chip clogging data are input into the second method, washer simulation, to design chip washers and washing cycles that can effectively remove the machining chips. The advantage of this methodology lies in its capability to quantify chip cleanliness risks as well as washing efficiencies with numerical quality indices, enabling comparisons of chip cleaning difficulties and evaluations of chip washer performance. The innovation of this methodology is the adaptation of a particle-based CFD method to model the behavior of machining chips as well as the dynamics of water jets in the chip washer.