Physics / Engineering
Alpha Stirling engine
Two pistons share one crankpin in a 90° V. Inspect the rod bearings, compare reservoir temperatures and explore a separate adjustable-crank teaching mode.
What happens
Two pistons share one crankpin in a 90° V. Inspect the rod bearings, compare reservoir temperatures and explore a separate adjustable-crank teaching mode.
Both connecting rods run on one crankpin. The 90° angle between cylinders fixes the piston phase lag at 90°. Teaching variant: two separately indexed crankpins on one shaft. Change the piston phase lag while the cylinder angle remains 90°.
Open the drive close-up and step the shaft by 45°. Ideal isothermal gas, perfect regeneration and prescribed shaft speed; heat transfer, friction and flywheel acceleration are not solved. Torque is indicated gas torque before external-pressure subtraction.
Try this
Inspect the shared crankpin and step by 45°. Shaft speed is prescribed; compare indicated work in the p–V loop.
Equations used in the module
Equations p = nR / (Vh/Th + Vc/Tc + Vr/Tr) Tr = (Th−Tc) / ln(Th/Tc) W = ∮ p d(Vh+Vc) τ = p d(Vh+Vc)/dθ P = W f
