Development of a new method for testing strength of cells against fluid shear stress

A new method for testing the strength of cells against fluid shear stress by using a long capillary column was proposed. The trajectories of cells in the column were simulated by introducing the Brownian motion model. The Brownian motion was performed by the generation of random numbers. The mean exposure time to shear stress and the mean shear stress acting on the surface of cells were discussed by the result of computer simulation. The mean shear stress acting on the surface of cells flowing in the capillary column was estimated as 4/3-fold of the shear stress at the column wall provided that the ratio of the cell radius to the column radius does not exceed 0.08. The effectiveness of this new method for testing the strength of cells against fluid shear stress was shown.List of Symbols a m radius of cell - c constant - E distribution function - L m length of capillary column - M number of division - N number of division - p probability - Q m³/s flow rate - R m radius of capillary column - r m radial position - t s time - T s exposure time - T _m s mean exposure time - T ₀ s mean residence time - m/s axial velocity - u _m m/s cross-sectional flow velocity - z m axial position - s^–1 shear rate - _w s^–1 shear rate at wall - Pa s viscosity - spherical coordinate - spherical coordinate - Pa shear stress - _m Pa mean shear stress - _w Pa shear stress at wall