A viscoelastic model of shear-induced hemolysis in laminar flow.

We present measurements of human blood hemolysis caused by laminar shear stresses ranging from 50 to 500 Pa for exposure times extending from 60 to 300 s using a Taylor-Couette device. A viscoelastic model is proposed that captures the response of the red blood cells to shear stress. The model is based on well-established mechanical properties of the red blood cell membrane, and shows good agreement with data from the experiments presented here, as well as data from the existing literature. Two characteristic time scales are identified: a fast time scale corresponding to the relaxation time of the red blood cell membrane and a slow time scale that represents the onset of plasticity and is related to hemoglobin release from a damaged cell. The model proposed here collapses the available data over almost five orders of magnitude in exposure time and shear stresses up to 500 Pa.