Free Piston Stirling Engine_ Expansion bellow concept

At partial loading conditions (without rotary mechanism and torque meter) the engine started at 190 oC. It achieved its maximum stroke of 54 mm at 390 oC. At full loading (with rotary mechanism and torque meter) the engine started at 310 oC and achieved the maximum measured power at 460 oC. At maximum loading it achieved a stroke of 3.1 mm, frequency of Hz and generated about 2.5 Watt. The power dissipated -at full load- in the torque meter, rotary mechanism, guiding system, expansion bellow and displacer were , , , and Watts respectively. The engine achieved % mechanical efficiency, 10.9% thermal efficiency and overall efficiency of %