  We present a rigorous procedure to derive coarse-grained red blood cell (RBC)
models, which lead to accurate mechanical properties of realistic RBCs. Based
on a semi-analytic theory linear and non-linear elastic properties of the RBC
membrane can be matched with those obtained in optical tweezers stretching
experiments. In addition, we develop a nearly stress-free model which avoids a
number of pitfalls of existing RBC models, such as non-biconcave equilibrium
shape and dependence of RBC mechanical properties on the triangulation quality.
The proposed RBC model is suitable for use in many existing numerical methods,
such as Lattice Boltzmann, Multiparticle Collision Dynamics, Immersed Boundary,
etc.
