Hematocrit Centrifuge: Blood Separation by Density

A microhematocrit centrifuge is one of the oldest and still most-used diagnostic tools in medicine: spin whole blood fast enough and long enough, and it separates into three visible layers purely by density — packed red cells at the bottom, a thin buffy coat of white cells and platelets above them, and straw-colored plasma on top. This simulator models that separation with real physics: Stokes' law drives each cell type's settling velocity under the centrifugal field, so red cells (densest) pack first, the buffy coat forms as a distinct band, and the live hematocrit readout climbs toward the patient's true red-cell fraction exactly as it would on a real spun tube read against a hematocrit chart. Adjust the rotor speed to change the relative centrifugal force (RCF), dial in a patient's true hematocrit to simulate anemia or polycythemia, and watch the tube tilt out to the horizontal as the rotor spins up, just like a real swinging-bucket rotor.