Exhaust pulse pressure charging (EPPC) is a system for supercharging

two-stroke A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes of the piston, one up and one down, in one revolution of the crankshaft in contrast to a four-stroke engine which re ...

diesel engine The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...

s of the loop-scavenge type. Loop-scavenge engines cannot be pressure-charged in the same way as uniflow engines or

four-stroke A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either directio ...

engines because the inlet and exhaust ports are open at the same time.

Overview

The engine usually has a

Roots blower The Roots blower is a positive displacement lobe pump which operates by pumping a fluid with a pair of meshing lobes resembling a set of stretched gears. Fluid is trapped in pockets surrounding the lobes and carried from the intake side to th ...

to provide air for scavenging and this is arranged to deliver excess air so that air follows the exhaust gases into the exhaust manifold. Some of this air is then forced back into the cylinder by a rise in pressure in the exhaust manifold resulting from the exhaust pulse from another cylinder. For additional pressure charging a

turbocharger In an internal combustion engine, a turbocharger (also known as a turbo or a turbosupercharger) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake air, forcing more air into th ...

may be fitted, in series with the Roots blower, but a turbocharger cannot be used alone as it would not provide enough air for scavenging at low speeds.

Examples

Exhaust pulse pressure charging was used by

Crossley Crossley, based in Manchester, United Kingdom, was a pioneering company in the production of internal combustion engines. Since 1989, it has been part of the Rolls-Royce Power Engineering group. More than 100,000 Crossley oil and gas engin ...

in these

diesel locomotive A diesel locomotive is a type of railway locomotive in which the prime mover (locomotive), power source is a diesel engine. Several types of diesel locomotives have been developed, differing mainly in the means by which mechanical power is con ...

engines: * the HST-Vee 8, used in the British Rail Class 28, the CIE 001 Class and the WAGR X class * the EST-Vee 8 used in the CIE 201 Class * the ESNT 6 used in British Rail Class D3/3 shunting locomotives

Sources

* Superchargers Two-stroke diesel engines Exhaust systems {{automotive-tech-stub

Overview

Examples

See also

Sources