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Use of surface texturing plays positive role for efficient and risk free operations of bearing. Hydrodynamic bearing are widely used in many rotating machineries for supporting loads due to which, the problem of instability occurs, that’s why dynamic performance parameters considered as important to be studied for journal bearing and the systematic diagram of hydrodynamic journal bearing is shown in figure 1. Therefore, it is essential for a designer to bring out the suitable texture distribution which enlarges its enhancement by providing maximal values of dynamic and stability performance parameters like stiffness, damping and threshold speed. In this regard, Ganji et al. (2014) investigated the influence of cylindrical textures on the dynamic performance of journal bearing by using finite difference method (FDM). They found that direct stiffness coefficients increases with increase in eccentricity ratio and direct damping coefficients decreases with increase in eccentricity ratio. The value of cross couple damping coefficient increases by increasing the eccentricity ratio.
Sharma and Yadav (2014) found that film stiffness and damping coefficient of psueoplastic lubricant is higher as compared to dilent and Newtonian lubricant. They also found that the value of fluid film stiffness of hybrid thrust bearing decreasing continuously with increasing in dimple depth.
Yadav and Sharma (2016) investigated the influence of hybrid circular thrust pad bearing by utilizing finite element method (FEM). They found that fluid-film stiffness and damping of psuedoplastic lubricant is higher as compared to dilent and Newtonian lubricant.
Matele and Pandey (2018) studied the effect of different micro-dimple having circular, square and densely distributed square on the journal bearing by utilizing laser surface texturing. They concluded that the direct stiffness coefficient in the axial direction improve for all geometrics of texture whereas the direct stiffness in circumferential direction and the direct damping coefficient in both direction decreases.
Wang et al. (2017) studied the effect of journal rotation and bearing surface waviness of hybrid journal bearing by using linear perturbation theory. They found that with the increase in eccentricity ratio and rotational speed, the principal stiffness may be increased and also by increasing eccentricity ratio and rotational speed, the value of principal damping decreased.
Sharma et al. (2020) considered the effect of dimple texture (triangular in shape) on the hydrodynamic journal bearing by utilizing FEM. They found that, at an eccentricity of 0.6, maximal value of threshold speed and direct stiffness is obtained at lower value of texture depth and the maximal value of direct damping is obtained at higher texture depth.
Jamwal et al. (2019) considered the effect of dimple texture (chevron in shape) on the hydrodynamic journal bearing by utilizing FEM. They found that maximum value of threshold speed is obtained at fully textured region distribution.
Jain and Bajpai (2014) investigated the effect of circular shape dimple on the hydrodynamic journal bearing by utilizing micropolar fluid to find the dynamic characteristic. They found that the value of stiffness and damping coefficient of a hydrodynamic journal bearing increases at higher coupling numbers and lower characteristic length.
Sharma and Awasthi (2016) investigated the effect of circular shape on the hydrodynamic journal bearing by utilizing FEM. They found that damping coefficients (CXX, Czz and CXZ) and Sxz increases with increase in L/D ratio. They also found that direct stiffness coefficient, Szx and the value of threshold speed decreases with increase in L/D ratio.
Kadda and Nadia (2020) studied the effect of textured and un-textured surfaces on the elastic behaviour of plain journal bearing by using FEM. They found that, at higher rotational speed, the important performance parameter of bearing (pressure, displacement and shear stress) of textured surface is higher as compared to un-textured surface.