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Inside a piston engine.

How does a piston turn a wheel?

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Original demonstrations by The Bugged Dev. The teaching models and interactions here are new implementations.

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Inside a piston engine.

How does a piston turn a wheel?

Setting up the engine…

Stroke: Ready
Crank turned: 0°

More

Intake valve: Closed
Exhaust valve: Closed

Fit the linkage and valves before turning the crank.

How does a piston turn a wheel?

The connecting rod converts the piston’s back-and-forth motion into crank rotation. Intake draws in a charge, compression squeezes it, combustion drives the power stroke, and exhaust clears the cylinder. Four strokes take two crank revolutions.

4 strokes = 720° of crank rotation

What this model simplifies

Ideal single-cylinder slider-crank model. Valve states at endpoints describe the stroke just completed; valves change at ideal stroke boundaries. This powered-cycle demonstration requires fuel and a positive crank-speed setting. Each half turn is slowed for inspection. Higher crank-speed settings shorten playback, but the displayed motion does not run at real RPM; zero speed or fuel stops a powered advance. The camshaft and thermodynamics are not simulated. Pressure values and thermodynamic efficiency are not predicted.

Read the source · www1.grc.nasa.gov ↗

Put it to work.

Assemble the linkage and complete intake, compression, power and exhaust.

Make it work.

Complete the four-stroke powered cycle.

Run

Fine adjustments 2

Fuel supply%

Crank speedrpm