Computed Synovial Fluid Flow in a Simple Knee Joint Model

Abstract

Prediction of shear stress induced by the fluid flow on knee joint cells is the main aim of this study. Oscillatory flow of a Newtonian synovial fluid is examined in two-dimensional joint geometries. The experimental model is a fluid driven shear loader test rig, which features a finite plate oscillating at 1Hz, that is 1mm over a stationary cell culture surface. Oscillating Couette flow in the thin gap is generated by the finite span plate. An incompressible two-dimensional transient and laminar CFD model is developed using the STAR-CD® code. The infinite oscillating plate Couette flow solutions (Stoke’s Second Problem with a finite gap) are reviewed and used in the grid sensitivity and validation tests of the computational finite oscillating plate model. The resulting flow features and vorticity convection are discussed and shear stress induced on the stationary plate due to an oscillating finite plate is compared with its infinite counterpart. As an extension, the effect of articular cartilage curvature is studied in a topologically equivalent model with and without menisci.