Properties of blood cells and their interaction determine their distribution in flow. It
is observed experimentally that erythrocytes migrate to the flow axis, platelets to the
vessel wall, and leucocytes roll along the vessel wall. In this work, a three-dimensional
model based on Dissipative Particle Dynamics method and a new hybrid (discrete-continuous)
model for blood cells is used to study the interaction of erythrocytes with platelets and
leucocytes in flow. Erythrocytes are modelled as elastic highly deformable membranes,
while platelets and leucocytes as elastic membranes with their shape close to a sphere.
Separation of erythrocytes and platelets in flow is shown for different values of
hematocrit. Erythrocyte and platelet distributions are in a good qualitative agreement
with the existing experimental results. Migration of leucocyte to the vessel wall and its
rolling along the wall is observed.