Rotational energy smoothing in engines The component that smooths out cyclic power impulses from the engine crankshaft is the:

Introduction / Context:
Reciprocating engines produce pulsating torque because each cylinder only fires intermittently. A device is needed to store energy during power strokes and release it during compression/exhaust strokes to smooth rotation.

Given Data / Assumptions:

• Conventional four-stroke engine with discrete firing events.
• Rigid crankshaft and drivetrain.
• A heavy rotating mass attached to the crankshaft.

Concept / Approach:
The flywheel provides rotational inertia, storing kinetic energy (E = 0.5 * I * omega^2). During power strokes it accelerates slightly; during non-power strokes it decelerates, evening out speed. Other components serve different roles: clutch disengages drive, differential splits torque left-right, torque converter fluid-couples the engine to the transmission in automatics but is not used on manuals and is not the primary smoothing device on the crank itself.

Step-by-Step Solution:
Identify the need: smooth angular velocity.Recall the part providing inertia: flywheel.Select 'flywheel' as the correct answer.

Verification / Alternative check:
Engines with lightweight flywheels exhibit more speed fluctuation at idle; multi-cylinder engines require smaller flywheels due to more frequent firing, confirming the effect.

Why Other Options Are Wrong:
Clutch couples/decouples power flow; differential distributes torque to wheels; torque converter adds hydrodynamic coupling but the core smoothing of crank pulsations is by the flywheel.

Common Pitfalls:
Confusing NVH damping with inertia; assuming torque converters are present on manuals; overlooking dual-mass flywheels designed to further isolate torsional vibrations.

Final Answer:
flywheel