According to the source, diesel engines achieve high torque output due to what combination?

According to the source, diesel engines achieve high torque output due to what combination?

• A. Slow speed characteristics and short crankshaft throws.
• B. Long strokes and high air intake.
• C. Rapid engine speeds with large displacement.
• D. High compression with no effect of crankshaft throws.

Answer: (A)

Diesel engines are designed to deliver strong torque at low speeds, and two mechanical traits help make that possible: operating at slower crankshaft speeds and keeping the moving mass lightweight with shorter crank throws. At low RPM, the engine has more time per cycle for the combustion energy to act, so the pressure developed translates into torque rather than being shed as rapid high-speed motion. Shorter crankshaft throws reduce the reciprocating inertia of the pistons and connecting rods, meaning less energy is wasted in accelerating heavy moving parts. Put together, these factors let the engine convert more of the combustion energy into turning the crankshaft, yielding high torque even at low speeds. The other ideas emphasize speed, displacement, or compression without addressing how reduced inertia from short throws complements slow-speed operation to boost torque.

Diesel engines are designed to deliver strong torque at low speeds, and two mechanical traits help make that possible: operating at slower crankshaft speeds and keeping the moving mass lightweight with shorter crank throws. At low RPM, the engine has more time per cycle for the combustion energy to act, so the pressure developed translates into torque rather than being shed as rapid high-speed motion. Shorter crankshaft throws reduce the reciprocating inertia of the pistons and connecting rods, meaning less energy is wasted in accelerating heavy moving parts. Put together, these factors let the engine convert more of the combustion energy into turning the crankshaft, yielding high torque even at low speeds. The other ideas emphasize speed, displacement, or compression without addressing how reduced inertia from short throws complements slow-speed operation to boost torque.