Parametric study of textured hydrodynamic journal bearing for turbulent flow using CFD analysis

Surface topology plays a pivotal role in improving the performance and longevity of the bearing in several ways, including lubrication, heat transfer, load distribution, adhesion, wear resistance, etc. The present study analyzed the effect of the micro-textured surface by using water as a lubricant on four different types of dimple geometries-cylindrical (I), A shape (II), triangular (III), and square (IV) dimples, on the dynamic characteristics of hydrodynamic journal bearings and carried out a comparative study with the non-textured bearings considering turbulent flow. The imperative dynamic characteristics of bearings’ maximum pressure and load carrying capacity were evaluated by changing the start angle, number of rows, radius of the circle circumscribing the dimple shape, axial gap, and depth of dimples. It is observed from the result that the shape, size, and distribution pattern of texture, are of paramount importance for the improvement of dynamic characteristics. Texture shape II performs better than other textures and texture shape I perform worse. The start angle ( \(\theta _0\) ${\theta }_0$ ), number of rows ( \(N_r\) $N_r$ ), and radius of the circumscribing circle ( \(r_g\) $r_g$ ) of the texture affect performance by \(1-12\%\) $1-12\%$ . The axial gap ( \(S_g\) $S_g$ ) and depth of texture (d) affect load capacity and maximum pressure by \(0-2\%\) $0-2\%$ . The number of rows ( \(N_r\in (1,10)\) $N_r\in (1,10)$ ) for start angle ( \(\theta _0=330^{\circ }\) ${\theta }_0={330}^{\circ }$ ) decreases the load capacity ratio ( \(W/W_0\) $W/W_0$ ) in the range 5–35%; and pressure ratio ( \(P/P_0\) $P/P_0$ ) in the range 2–16%; texture-II beating others shapes. The effect of \(N_r\) $N_r$ is less prominent (decrease of 2–10%) for the case of \(\theta _0=10^{\circ }\) ${\theta }_0={10}^{\circ }$ as compared to the case of \(\theta _0=330^{\circ }\) ${\theta }_0={330}^{\circ }$ .