Dowtherm A, Thermal Expansion Coefficient? 2

[rocketscientist]

Does anyone have the thermal expansion coefficient for Dowtherm A? I will need to size a PSV for thermal expansion. I need it at about 315 C and 260 C.

Thanks

 

[dogtop]

http://www.dow.com/PublishedLiterat...rans/pdfs/noreg/176-01463.pdf&fromPage=GetDoc

 

[rocketscientist]

Actually, I have this sheet and it does not provide the liquid expansion coefficient.

 

[dcasto]

Calculate it from the density vs temp table.

 

[rocketscientist]

Okay,

Thanks, I guess sometimes, I've forgotten more than I know. Here's how to work it out:

alpha = 1/V (dV/dT) solving for the integral:

Integral(alpha dT) = Integral (dV/V)

Solving for T1, T2, V1, V2:

alpha = ln(V2/V1)/(T2-T1)

Where to get Vs:

Assume a 1 lbs. basis: V = W(1 lbs.)/density @ T

Substitute V2, V1 for T1, T2 and solve for thermal expansion over the interval.

Reference:

http://en.wikipedia.org/wiki/Thermal_expansion

Thanks,

 

[unclesyd]

You might want to get the data disk for Therminol VP-1, the same as Dowtherm A.

Dow also has a booklet on Dowtherm A.

http://www.therminol.com/pages/tools/toolscd.asp