expansion stroke


Also found in: Medical.

expansion stroke

The stroke in the operating cycle of a reciprocating engine in which both the inlet and exhaust valves are closed, the fuel-air mixture has been ignited and burned, and the piston is being forced downward by expanding gases. This is the only stroke in which power is produced. Also called the power stroke
References in periodicals archive ?
Looking at Figures 11, 12, 13, the vortex chamber shows a higher pressure and continually rising cumulative apparent heat release in the expansion stroke compared to the non-vortex counterpart.
The delay in delivering the retarded spark allows the piston to start moving downward on its expansion stroke before the ignition actually occurs.
Linear free piston engines can capture a much greater proportion of the energy contained in the fuel burnt, not only because the linear gas expander extracts electrical power directly from the expansion stroke, but also by optimising the motion of the piston to improve combustion efficiency.
0K2, featuring Honda s EXlink (Extended Expansion Linkage Engine), featuring an expansion stroke longer than its intake stroke, resulting in a high expansion ratio for greatly increased thermal and fuel efficiency.
0K2, featuring Honda's EXlink (Extended Expansion Linkage Engine)(2), featuring an expansion stroke longer than its intake stroke, resulting in a high expansion ratio for greatly increased thermal and fuel efficiency.
At low crankshaft revolutions values (under 2500rpm) the top pressure decrease is caused mainly by the considerable increase of the fast combustion phase duration, the point in which the top pressure occurs moving towards the expansion stroke (Fig.
Regenerating the filter requires altering the amount of air and fuel fed into the engine, and can be supplemented by feeding unburned fuel into the NOx catalyst during the expansion stroke.
C-Brake makes use of a hydraulic circuit to open cylinder exhaust valves during the engine's expansion stroke.
The compression and expansion lines almost overlay, indicating almost all the work done during compression is recovered during the expansion stroke, and the linearity of the process lines indicate these are polytropic with a similar polytropic index value.
The increased expansion stroke makes 5% to 10% more force and thus energy added to the piston which in turn, adds torque to the crankshaft.
This is consistent with the detrimental impact on both fuel consumption and knock margin, and again suggests that the high TKE and piston speed are disadvantageous under the lower temperature, dilute conditions of combustion later in the expansion stroke.
However, at the beginning of the expansion stroke, the combustion chamber opens into a larger area that has rather larger SA/V than piston engines.