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If it's possible,

If it's possible,

If it's possible,

(OP)
how do I calculate how much force is necessary to prevent metal from expanding because of a temp. rise?

RE: If it's possible,

You calculate the thermal expansion of the material and the force required to deflect it back in to place.

Garland E. Borowski, PE
Engineering Manager
Star Aviation

RE: If it's possible,

.......which is an application of Castigliano's second theorem – for displacements in a linearly elastic structure

Castigliano's method for calculating forces is an application of his first theorem, which states:

If the strain energy of an elastic structure can be expressed as a function of generalised displacement qi; then the partial derivative of the strain energy with respect to generalised displacement gives the generalised force Qi.

http://en.wikipedia.org/wiki/Castigliano%27s_method

John

RE: If it's possible,

or you can use the easier familiar relationship to students of Strength of Material. Must assume a compact element.
           S=E*e which can be in this other form
         F/A=E*dl/L
        S=compressive or tensile stress;E=modulus of eleasticity;e=strain;F=force; A=cross sectional area;dl= increase or decrease in length;L=original length before heating or cooling.

RE: If it's possible,

Hooke's law, I believe, since we are giving names to various formulae.

RE: If it's possible,

(OP)
Thanks, folks. . .
This last one I must have learned at some point.  
I guess I didn't apply it to other than textbook problems, and by the time I needed for the real world, I forgot I knew it.
Or some such thing. . .?

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