Volume versus temperature

1. Jan 5, 2013

spaghetti3451

1. The problem statement, all variables and given/known data

Many automobile engines have cast-iron cylinders and aluminium pistons. What kinds of problems could occur if the engine gets too hot? (The coefficient of volume expansion of cast-iron is approximately the same as that of steel.)

2. Relevant equations

Relation of volume to temperature

3. The attempt at a solution

The coefficient of volume expansion of steel is 4.8*10-5(C°)-1. I don't see the relevance here of this numerical value. Do you?

The problems I could come up with:

1. The cylinders and pistons would expand and frictional forces would act between the cylinders and the pistons. This would lead to a slower rate of speed of the automobile for a given rate of fuel consumption.

2. Any others???

2. Jan 5, 2013

rock.freak667

If there is too much friction, what will happen to the temperature of the pistons and hence what can happen to its diameter?

3. Jan 5, 2013

mrcotton

How will each expand?
Look at the values of the Coefficients of Thermal Expansion in the table of the website
http://physics.info/expansion/
Why do piston rings have a gap in them?
The website talks about Concorde, I once read that the Lockheed SR-71 Blackbird dripped fuel on the runway and only after heating up and expanding was it fuel tank sealed.

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