Aspiration
The Roots blower is commonly used on the two stroke diesel engine, which requires some form of forced induction. In this application, the blower does not provide significant boost and these engines are considered naturally aspirated with the blower providing just slightly more than positive pressure as the device is acting as a positive displacement pump; turbochargers are generally used when significant boost is needed. In small engines, a conventional turbo will be followed by the blower. In large engines, particularly in railroad, marine or stationary services, the turbo is a combination turbo-compressor, with the compressor being driven by the crankshaft through an overrunning clutch during starting and at low rpms, and by the turbine with the clutch being disconnected when the exhaust gasses have reached sufficient temperature.
Read more about this topic: Two-stroke Diesel Engine
Famous quotes containing the word aspiration:
“Half of my life is gone, and I have let
The years slip from me and have not fulfilled
The aspiration of my youth, to build
Some tower of song with lofty parapet.”
—Henry Wadsworth Longfellow (1809–1882)
“I should think the American admiration of five-minute tourists has done more to kill the sacredness of old European beauty and aspiration than multitudes of bombs would have done.”
—D.H. (David Herbert)
“My aspiration now is to get by luck what I could not get by merit.”
—Mason Cooley (b. 1927)