Did you know …
The average temperature of the exhaust gas, at the entry point to a diesel turbo, is 800 degrees centigrade. A petrol engine can reach 1,000 degrees, glowing bright yellow. Hot enough to melt window glass.
A new generation turbo’s impellers rotate at up to 220,000 revs per minute. The impellers on a Boeing 747 engine rotate at about 7,000 revs in comparison.
The speed of the air meeting the compressor blades at the turbo intake will often exceed the speed of sound (Mach 1).
At average engine revs, a medium size turbo will swallow 130 cubic feet of air per minute, equivalent to the interior volume of a Transit van.
Turbocharger balance is crucial – imbalance at maximum revs equivalent to a 1 kilogram force is normally acceptable. Poorly balanced turbos supplied for service will often have up to 6 kilograms of imbalance. This is equivalent to driving along with a brick attached to your wheel rim!
The “hot end” turbine blades in a turbo, are made from a high nickel content alloy, as used in jet aircraft engines. The blade tip will typically travel at speeds up to 900 MPH (400 meters per second) in normal operation.
A turbo will accelerate from 20,000 revs per minute to over 150,000 revs per minute in less than one second.
You do now …