blowby


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blowby

[′blō‚bī]
(mechanical engineering)
Leaking of fluid between a cylinder and its piston during operation.

blowby

The loss of pressure in the cylinder of a reciprocating engine resulting from the leakage of burned gases past the piston rings.
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Higher-mileage cars tend to have increased blowby, and blowby is one of the factors found in the literature review affecting GDI IVD.
For highly boosted TGDI engines, the blowby recirculation reaches its maximum in the LSPI zone on the engine speed-load map [11].
Crankcase ventilation filter systems that keep oily blowby from coating turbochargers and precision components are introduced.
Dependent on this, there is a reduction in trapped mass of up to 70% due to blowby during the settling period.
By neglecting valve leakage and blowby, we may assume conservation of mass m during the combustion cycle:
For aircraft engines, which eat a lot of lead and have more blowby than auto engines, I prefer a mineral basestock, which has better solvent characteristics than the semi-synthetic basestocks used in the Shell and Exxon products.
* As MLRSs grow older, the engines often have more of a blowby problem, no matter how careful you are about proper idling.
Blow-by emissions can be as much as 25 percent of the total emissions (tailpipe and blowby) over an FTP transient cycle.
The blowby of the real engine is decreasing with higher engine speeds, so that the pressure difference in comparison with the simulation is negative for high engine speeds, and vice versa for lower engine speeds.
Leakage of gases from the combustion chamber past the piston rings is often referred to as blowby. These gases pass into the engine crankcase, where they are vented to prevent excessive pressurization.
Looking only at the single-cylinder lab engine (CLR) tests using aircraft oil and ZMax (AvBlend), however, still shows 17-percent reduction in blowby, a six-percent reduction in piston-skirt wear, a two-percent reduction in exhaust-valve wear, and about an 8.5-percent gain in power and efficiency.
While operating the engine in this way, the only way for the cylinder to breathe was by blowby losses past the rings.