(Automotive engineering: Vehicle components, Engine, transmission, and exhaust) The clearance volume is the volume remaining above the piston of an engine when it reaches top dead center.
⇒ The maximum compression pressure in the piston is controlled by the clearance volume. ⇒ When the piston is at top dead center, the clearance volume is at a minimum. When the piston moves to bottom dead center, it is at a maximum. ⇒ The nominal volume of the combustion chamber above the piston when it is at the top
dead center is the clearance volume.
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