To solve the problem associated with the cryogenic cooling approach and the one with the chilled air approach, an actively cooled coolant approach is proposed and examined. The proposed cooling system is also able to reduce the time period to reach the equilibrium state to enhance productivity. An active cooling prototype was developed that utilizes a compact air conditioner design, which is easy to use, movable, and can be easily fitted into different type of machine designs with relatively low costs. The system is based on the use of forced convection of the heat generated during the machining process. Experimental and computational studies of the effects of actively cooled coolant for grinding brittle materials are carried out. The experimental results show that the use of actively cooled coolant is able to improve surface quality for up to 13.1% on average in terms of surface roughness Ra. The results of optical and SEM examinations confirmed that the proposed approach is advantageous. Computational testing results show that the heat can be taken away more effectively by using the proposed approach.

Abstract. An active cooling and activation approach for coolant during ductile material grinding is proposed and examined. The aim is to enhance the surface quality of the workpiece being machined by the grinding process. Problems in the existing cooling approaches, such as activation, cryogenic cooling, and chilled air cooling, are discussed. Experimental and computational studies of the effects of actively cooled and activated coolant for ductile material grinding were conducted. Experimental results show that the proposed approach is able to improve surface quality by up to 36.68% on average in terms of surface roughness R a . In addition, it was found that surface roughness could be reduced if the coolant temperature is reduced. The results of the XRD tests show that the proposed method could, in general, produce low residual stress values. Further studies of this topic are necessary. Results of optical and SEM examinations also confirmed that the proposed approach is advantageous.

In order to enhance the cooling performance, better understanding of the effects of coolant parameters is necessary. In this project, a total of five input parameters for actively cooled and activated cutting fluid were studied. An aerosol spectrometer was used to measure the particle size spatial distribution of the cooling mist in the fluid. Taguchi method was used in the design of experiments. It was found that the unit volume net specific particle counts exhibit the behavior of oscillation and attenuation of a second order dynamic system. Cooling mist particle spatial frequency ranges from 0.01269/μm to 2.5/μm, the weighted average size ranges from 0.3051μm to 3.714μm and the particle size difference for 99.8% count attenuation ranges from 0.5μm to 19.7μm. The order of importance of the input parameters was studied and the coolant concentration was found as the most important input parameter for the unit volume net particle counts.