The recent developments in computational fluid dynamics (CFD) can be useful in observing the detailed haemodynamics in renal artery bifurcation for clinical evaluation and treatment. The present study focuses on haemodynamic behaviour of blood as it flows through the abdominal aorta-renal artery junction in an idealistic healthy artery with varying bifurcation angles to the abdominal aorta, i.e. from 30° to 90° with increments of 15°. This is to examine the effect of angulation on the junction and to determine whether arterial geometry plays a role in the prediction of atherosclerotic lesions. The three-dimensional models used in this study were generated using ANSYS WORKBENCH 19.0, and numerical simulation was done using FLUENT 19.0 solver. The blood flow is assumed to be Newtonian, incompressible and laminar. Haemodynamic parameters such as velocity, wall pressure and wall shear stress along with flow variation are compared among the different models. As the angulation increased, velocity and wall shear stress at the ostial region decreased by 14% and 52% respectively. Wall pressure at the same region saw an increase by 3%. Therefore, renal arteries with higher bifurcating angles to the abdominal aorta were observed to be more prone to the formation of atherosclerotic lesions. The present study is a precursor for future studies on renal artery with stenosis.

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Paper deals with the effect of turbulence on steady state performance characteristics of an eccentrically loaded 120° single pad externally adjustable fluid film bearing. The bearing has an aspect ratio of one and operates over a wide range of eccentricity ratios and adjustments. Two load-offset positions (β/χ) of 0.45 and 0.55 are considered in the present analysis. Reynolds equation incorporated with the Linearized turbulence model of Ng and Pan is solved numerically using finite difference method. A comparative study predicts that, load capacity of a bearing operating with β/χ = 0.55 and Re = 16000 is superior for negative radial and tilt adjustment configuration of the pad.