Bleeding simulation with physical viscoelasticity in smooth particle hydrodynamics

Being composed of blood cells and plasma, the blood flow has different rheological properties from common fluids. The viscoelastic properties of blood not only affect the flow characteristics of blood but also influence the shape of bleeding. In order to achieve the bleeding simulation with physical viscoelastic, we consider the effect of the aggregation behavior of red blood cells on the bleeding process. The elastic force caused by viscoelastic fluid elasticity is incorporated into the standard Navier–Stokes momentum equation, and an improved momentum equation that characterizes the rheological characteristics of viscoelastic blood is constructed. The effect of introducing elastic force on the particles motion is analyzed from the microscopic particle perspective by designing a two-dimensional particle system. The results of bleeding simulation show that the improved method eliminates the discontinuous boundary due to blood gushing out of the wound and forms irregular bleeding shapes in the bleeding process. In addition, the viscoelastic bleeding simulation exhibits a similar bleeding effect without distortion when the number of particles decreases, which further proves the reliability of proposed method.