Modeling Hemodynamic Tolerability of Short-Radius Artificial Gravity

Human physiology is not suited for long-term spaceflight. Spending prolonged periods of time exposed to microgravity leads to cephalad fluid shifts, cardiovascular deconditioning, and Spaceflight Associated Neuro-ocular Syndrome (SANS). A proposed countermeasure to reduce these risks is to generate artificial gravity with a short-radius centrifuge, since it can restore mechanical loading; however, its effective gravity increases with radius, producing large head-to-foot hydrostatic pressure gradients that may lower pressures near the head while increasing pressures in the lower extremities. Determining whether a given centrifuge configuration is hemodynamically tolerable requires modeling both whole-body pressure and flow redistribution, as well as local vessel-level fluid mechanics. This presentation will describe a combination of models that uses the lumped-parameter whole-body cardiovascular simulator CVSim to predict time-resolved systemic pressures and flows under baseline and centrifuge conditions. The CVSim outputs are then used as physiologically grounded boundary data for a 3D incompressible Navier–Stokes model to quantify local quantities such as pressure-drop pulsatility and wall shear stress. Together, these models provide complementary safety-relevant predictions that neither approach can supply alone.