Abstract
In grinding process, the rotation of a grinding wheel has significant effects on the flow of air and/or grinding fluid around the wheel and workpiece. The permeability of a grinding wheel which corresponds to the grain size plays the main role in the flow through a porous media. The thermal behaviour around the workpiece surface is closely related to the flow pattern around it, and they influences the thermal deformation of a workpiece which is concerned with the machining accuracy of grinding. In addition, to design a rational grindng fluid application system, it is necessary to clarify the thermal behaviour and flow pattern around it. Here experiments were carried out in a dry surface grinding process to measure the distributions of the wall pressure and of the local heat transfer at the workpiece surface. Using the flow visualization by the fluid film and surface tuft methods, the air flow pattern around it was also observed. From the experimental results, it is clear that the grain size of a grinding wheel has a remarkable influence on the thermal behaviour and flow pattern. The air blowing out from the grinding wheel which is caused by the centrifugal force may be considered to act as an impinging jet to a workpiece surface.
