Application of Lubrication Theory to Fluid Flow in Grinding: Part I—Flow Between Smooth Surfaces

Abstract

The present paper, which consists of two parts, proposes models of fluid flow in grinding with nonporous wheels. In this first part, a smooth wheel is employed instead of a rough grinding wheel to simplify the analysis. Fluid flow is investigated for laminar and turbulent regimes using the classical Reynolds equation of lubrication and a modified Reynolds equation for turbulent flows, respectively. The applicability of the proposed models is discussed and verified experimentally in terms of the developed hydrodynamic pressure. It is found that the classical Reynolds equation reliably predicts the hydrodynamic pressure if the Reynolds number Re (based on the minimum gap size) is lower than about 300. Experimental results for 300<Re<1500 agree with the proposed turbulent flow model. This suggests that the flow in this range of Re is turbulent, and that the fluid inertia is negligible. The influence of wheel roughness is investigated in Part II.

Modeling and Experimental Investigation of Pressure Field in the Grinding Zone with Nanoparticle Jet of MQL

“…Yet when the ratio of the grinding liquid in the grinding zone reached a certain value, it will increase with the increasing flow. Hryniewicz [15] conducted experiments of two grinding liquids (the oiliness grinding liquid and chemical synthetic fluids) and found that in the same experimental conditions, the maximum dynamic pressure generated by the oiliness of the grinding liquid was much larger than that from chemical synthetic fluids. In this research, the modeling and experimental investigation was conducted on nano-particle jet flow of MQL grinding pressure field.…”

“…With the simulating calculation, the larger the velocity of grinding wheel is, the larger the normal force will be. Hryniewicz et al [15] applied two types of nozzles in the experiment of cooling system. The first was formed by two nozzles, and the main nozzle was used to the feeding of the grinding liquid, and the assistant nozzle was used to break through "airbond" of air flow around the grinding wheel.…”

“…Based on two-dimensional steady incompressible fluid Navier-Stokes equation, the fluid equation in grinding zone was deducted in planar grinding, and the dynamic pressure of the fluid was simulated and solved, which was verified in experiments. Hryniewicz et al [15,16] considered the influence of the roughness and established a two-dimensional mathematical model. The regularities of distribution of the dynamic pressure were simulated and solved, which was verified in experiments.…”

Modeling and Experimental Investigation of the Flow Velocity Field in the Grinding Zone

“…High normal force was measured, caused by the fluid contact pressure. The normal force increased with wheel speed and delivered flow rate [18][19][20]. Frank et al pointed out that hydrodynamic lift force is remarkably high in the overall grinding resistance, and suggested that a grooved wheel was effective to release the pressure generation [21][22].…”

Nanomanufacturing : nano-structured materials made layer-by-layer.

“…Many extensions of this basic theory exist, including elastohydrodynamic lubrication [Greenwood (1972), Taylor and O'Callaghan (1972), Oh and Huebner (1973), LaBouff and Booker (1985), Jones (1993) [Constantinescu (1959), Ng (1964), Elrod and Ng (1967), Hirs (1973)], and lubrication of non-Newtonian fluids [Ng and Saibel (1962), Swamy et al (1977), Johnson1993, Bhattacharjee and Das (1996), Hryniewicz et al (2001), Nair et al (2007), Mongkolwongrojn and Aiumpronsin (2010)], among others [Christensen (1971), Eringen and Okada (1995), Feng and Weinbaum (2000), Stone (2005), Jang and Khonsari (2005), Bujurke and Kudenatti (2007), Rojas et al (2010)]. Recent books by Hori [Hori (2006)] and Szeri [Szeri (2010)] thoroughly review the history and applications of lubrication theory and derive the governing equations.…”