You could have split forced induction into Turbocharging and Supercharging.
The turbocharger is driven by exhaust gas, while the supercharger is driven directly from the crank, usually by a belt. This difference in drive causes the major division between the two - the characteristic called "turbo lag". This is the delay that the turbocharger spends waiting for the engine to produce enough exhaust to spin up the charger and deliver boost. Play bike games, bike games online free.
Turbochargers experience this lag as an intrinsic part of their nature. Turbo fans don't care because they're interested in the high end performance anyway. Being driven by the vehicle's own exhaust means a turbocharger tends to reflect and amplify the breathability characteristics - highs and lows - of the vehicle throughout its powerband. west full flavour
Superchargers are driven continuously while the motor runs, like a fan or air conditioner, and run at a fixed ratio to the engine rpm, delivering the same curve of boost regardless of the engine's natural aspiration, so they tend to impose their own characteristics on the vehicle's breathability. But some of them can deliver instant boost practically from idle, which is held to be the great differentiator between the turbo and the supercharger.
See our individual pages for better detail on each, but here's a very crude summary of the four popular methods of Forced Induction in automobile and marine engines today:
1. A turbocharger is an air pump driven by exhaust gas, pumping air it has ALREADY compressed. It delivers exponentially increasing boost as rpm increases.
Some like to say a turbocharger is a centrifugal supercharger driven by exhaust instead of mechanically, the only difference is the way the system is powered. [also see the Turbochargers page]
Or you could have split it between the way the compressors are driven.
2. There are two types of supercharger and the first, a centrifugal supercharger, is an air pump driven directly from the crank, injecting air it has ALREADY compressed. It delivers exponentially increasing boost as rpm increases.
Some like to think of the centrifugal supercharger and the turbocharger as the same thing except with the compressor wheel turned by different means. The centrifugal does experience lag at the lower end also. [also see the Centrifugal Superchargers page]
Or you could have split it between compressors and (positive displacement) non-compressors.
3. Of the two types of supercharger the second, commonly called a Roots blower, is a positive displacement air pump driven directly from the crank, injecting air it has NOT compressed. It delivers linearly increasing boost as rpm increases.
The great difference of the roots type blower is that it produces high boost at low end rpm, with no significant lag. [also see our Roots Superchargers page]
But now you have to split it between NON-positive displacement compressors, positive displacement NON-compressors, and the twin screw positive displacement compressor.
4. The twin-screw supercharger is a positive displacement air pump driven directly from the crank, injecting air it has ALREADY compressed. It delivers linearly increasing boost as rpm increases. The twin screw delivers full boost at low rpm, like the Roots, but also delivers compressed air, like the centrifugal and the turbo.
[also see our Twin Screw Superchargers page]
NOTES
Although both its original inventor Lysholm and its foremost American producer Whipple call it a positive displacement compressor, one commentator in Motor Sports Digest has suggested making the twin-screw its own new category of supercharger. Nice thought.
And take a look at our Supercharger Comparison Chart for the different performance characteristics between the turbocharger, the centrifugal supercharger, the roots supercharger, and the twin screw supercharger.
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