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It often disperses downwind in a pattern called an exhaust plume. It is a major component of motor vehicle emissions (and from stationary internal combustion engines), which can also include crankcase blow-by and evaporation of unused gasoline. Air pollution from burning fossil fuels is estimated to kill over 5 million people each year.
A 4-2-1 exhaust system is a type of exhaust manifold for an engine with four cylinders per bank, such as an inline-four engine or a V8 engine. The layout of a 4-2-1 system is as follows: four pipes (primary) come off the cylinder head , and merge into two pipes (secondary), which in turn finally link up to form one collector pipe.
Shock diamonds are the bright areas seen in the exhaust of this statically mounted Pratt & Whitney J58 engine on full afterburner.. Shock diamonds (also known as Mach diamonds or thrust diamonds, and less commonly Mach disks) are a formation of standing wave patterns that appear in the supersonic exhaust plume of an aerospace propulsion system, such as a supersonic jet engine, rocket, ramjet ...
When the descending piston first exposes the exhaust port on the cylinder wall, the exhaust flows out powerfully due to its pressure (without assistance from the expansion chamber) so the diameter/area over the length of the first portion of the pipe is constant or near constant with a divergence of 0 to 2 degrees which preserves wave energy.
Scavenging is the process of replacing the exhaust gas in a cylinder of an internal combustion engine with the fresh air/fuel mixture (or fresh air, in the case of direct-injection engines) for the next cycle. If scavenging is incomplete, the remaining exhaust gases can cause improper combustion for the next cycle, leading to reduced power output.
The first use of plasma engines was a Pulsed plasma thruster on the Soviet Zond 2 space probe which carried six PPTs that served as actuators of the attitude control system. The PPT propulsion system was tested for 70 minutes on 14 December 1964 when the spacecraft was 4.2 million kilometers from Earth. [6]
The mechanism by which exhaust emissions are controlled depends on the method of injection and the point at which air enters the exhaust system, and has varied during the course of the development of the technology. The first systems injected air very close to the engine, either in the cylinder head's exhaust ports or in the exhaust manifold.
Plume shapes can be influenced by flow in the ambient fluid (for example, if local wind blowing in the same direction as the plume results in a co-flowing jet). This usually causes a plume which has initially been 'buoyancy-dominated' to become 'momentum-dominated' (this transition is usually predicted by a dimensionless number called the ...