Proposed is a displacement dwell mechanism for increasing Stirling engine power output and efficiency. The dwell mechanism allows for deviations from a sinusoidal displacement profile found in crank-driven Stirling engines. Longer dwell allows slightly more time for heat transfer to occur in both the hot- and cold-side heat exchangers. Preliminary simulations using freely available Stirling engine simulation code by Israel Urieli indicates that even a modest increase in dwell time increases power output and efficiency. Increasing the power output and efficiency of a Stirling engine by way of a simple mechanical device represents the ?low hanging fruit? compared to complex and expensive regenerator/heat exchanger optimization and development.
Potential NASA Commercial Applications: The NASA applications for a Stirling power conversion system having higher efficiency and higher power density are long duration missions far from the sun, and missions in hostile environments and other cases where photovoltaic systems cannot meet the power generation requirements.