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Liquid jets in surrounding air face capillary and shear forces which eventually disintegrate the jet into droplets or spray. The instabilities developed in the flow inevitably break down an initial laminar (coherent) jet into a turbulent one. In the manufacturing process called grinding, one of the oldest approaches of shaping metals and other materials, liquid coolant jets are frequently used. A non-coherent or turbulent jet has a reduced flow rate due to cavitation, air entrapment and atomization of the fluid particles. The jet spread does not allow the coolant jet to effectively breach the high-speed rotating air layer, created by entrainment of air along the surface of rapidly rotating grinding wheel. The coherent, nearly columnal jet should be sufficiently long to maintain its initial velocity to penetrate the layer of air rotating with the grinding wheel. Thus, in many critical grinding applications, it is advised to use a coherent jet instead of a spray to eradicate defects of ground surface. In this study, we present simulations of liquid jet flows to see how the jet develops and breaks due to surface tension and shear forces. Creating an accurate model to predict liquid jet characteristics, especially for high-speed applications such as grinding wheel cooling would require wellresolving numerical grids and turbulence model selection. The problem being multi-phased with a density ratio of coolant-to-air being order of 1000 adds to the computational complexity. The presented numerical model and results are different compared to the previous simulations of liquid jets as the characteristics of jet disintegration are explored under conditions that closely resemble a grinding cooling application. Finite volume discretization of the flow domain and calculation of flow field characteristics were done by commercial software ANSYS Mesh and ANSYS Fluent modules, respectively. The numerical calculation and visualization of disintegration of free jet and the jet impinging into grinding wheel will be presented.