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One of the present industrial requirements is the development of high-speed, high load-carrying capacity machines. The problem of instability in high-speed conventional fluid film bearings can be prevented with the use of externally adjustable fluid film bearings. In the present study, the elastohydrodynamic behavior of a single pad externally adjustable fluid film bearing is reported for radial and tilt adjustment of the pad in the upward direction. Using the computational fluid dynamics (CFD) technique, a numerical study has been performed to measure fluid pressure generation for various eccentricity ratios. Later bearing deformation and stresses developed in the bearing are predicted using ANSYS commercial software. The current numerical method, which can be used to solve complex bearing models, has been evaluated against previously published literature, and the findings are in good agreement. The results of the CFD study indicate that bearing performance is superior when the pads are adjusted in the upward direction at a larger eccentricity ratio. Under the same geometric modification, design parameters such as fluid pressure, pad deformation, and stresses are evaluated and compared using the one-way and twoway fluid structure interaction (FSI) technique. These two-way FSI results help in the bearing design stage.

Abstract. Thermal efficiency and power output of gas turbines increase with increasing turbine rotor inlet tem[1perature. The rotor inlet temperatures in most gas turbines are far higher than the melting point of the blade material. Hence the turbine blades need to be cooled. In this work, simulations were carried out with the leading edge of gas turbine blade being internally cooled by coolant passages with V-shaped ribs at angles of 30°, 45° or 60° and at three aspect ratios (1:1, 1:2 and 2:3). The trailing edge of the blade was cooled by cylindrical and triangular pin-fin perforations in staggered and inline arrangements. Numerical analyses were carried out for each configuration of the cooling passages. The best cooling passages for leading edge and trailing edge were deduced by comparing the results of these analyses. It was found that using V-shaped ribs and fins induces a swirling flow, which in turn increases the velocity gradient and hence produces an improvement in heat transfer. The results show that under real time flow conditions, the application of V-shaped ribs and pin-fin perforations is a very promising technique for improving blade life.

Fluid film bearings are well suited for high-speed industrial machineries like turbine generators and marine propulsion systems. Several numerical methods are employed to theoretically investigate the flow phenomenon and performance parameters of journal bearings, operating under various conditions. This paper reviews various Computational Fluid Dynamics (CFD) and Fluid–Structure Interaction (FSI) techniques that are adopted to solve the flow equations pertaining to fluid film bearings. This review attempts to highlight the importance of cavitation, temperature, and their effect on bearing performance using CFD and FSI techniques. A comparison of various performance parameters in the form of load-carrying capacity, oil flow rate, friction as well as deformation and stresses developed in the bearing element due to oil film pressure using CFD and FSI, are also presented. Observations from the reviewed literature are presented which aims to benefit the researchers working in the field of both CFD and FSI analysis on hydrodynamic journal bearing. Graphical Abstract This review article emphasized the significance of cavitation and temperature effects on journal bearing performance using CFD and FSI techniques.