## 4 Results and Discussion
Figure 10 further confirms that the angular region spanning 270-330\({}^{\circ}\) represents the core pressure zone in two-lobe journal bearings, establishing this sector as the optimal location for precision surface texturing applications. Figure 11 demonstrates how texture depth variations (cubic, cylindrical, and semi-ellipsoidal geometries) affect the load capacity of two-lobe noncircular journal bearings. The data reveal that surface textures within the 270-300\({}^{\circ}\) angular region enhance bearing load capacity across all geometry types. This improvement occurs primarily at shallow penetration depths, with diminishing returns observed beyond optimal depth thresholds. Cubical textures generate the most substantial load capacity enhancement among the three geometries examined. However, relocating textures to the 300-330\({}^{\circ}\) sector reverses this trend, with cubic textures exhibiting the most significant load capacity reduction under these conditions. Figure 11: The effect of the geometric shape of surface textures on the load carrying capacity of two-lobe bearings as a function of texture depth. This analysis establishes that the 270-300\({}^{\circ}\) angular sector represents the optimal texturing zone, whereas the 300-330\({}^{\circ}\) region proves disadvantageous for surface texture application on two-lobe journal bearing interiors when enhancing load capacity relative to untextured configurations. Careful examination of load capacity variations relative to texture depth modifications reveals distinct optimal depth values corresponding to peak performance points for each geometry type. The analysis shows cubic and cylindrical textures in the lower lobe's high-pressure region achieve maximum effectiveness at shallower penetrations, while semi-ellipsoidal geometries require greater depths for optimal performance. Figure 12 demonstrates how strategically oriented surface textures of varying geometries influence rotor attitude angle within two-lobe bearing clearances across different penetration depths. The graphical data reveal distinct behavioral patterns for textures positioned at two circumferential locations (270-300\({}^{\circ}\) and 300-330\({}^{\circ}\)), identified as strategic angular sectors for surface modification in such rotor-bearing systems. Analysis of Figure 12 indicates that texture implementation within the 270-300\({}^{\circ}\) region induces significant attitude angle reduction, though this effect diminishes beyond certain depth thresholds. Notably, cubic textures exhibit the most pronounced influence on angular orientation among the three geometries studied. In contrast, texture placement in the 300-330\({}^{\circ}\) region produces irregular attitude angle variations that lack consistent correlation with increasing penetration depth. The variations in bearing attitude angle shown in Figure 6 reflect vertical displacement of the rotor center within the clearance space to maintain vertical alignment of the resultant load under various operating conditions. Texturing the high-pressure bearing region (270-300\({}^{\circ}\) angular sector) initially reduces the attitude angle up to a critical depth for all geometry types, indicating rotor equilibrium at lower positions. Beyond this threshold, further depth increases reverse this trend. According to the graphs in Figure 12, it can be seen that cubic surface textures achieve maximum attitude angle reduction at shallower penetration depths compared to cylindrical and semi-ellipsoidal configurations. The linear dynamic analytical model yields critical rotor-bearing system parameters characterizing dynamic rotor behavior within the two-lobe bearing clearance space. This for  
Figure 12: Effect of the geometric shape of surface textures on the rotor attitude angle in two-lobe bearings as a function of texture depth.