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Topic: Finding a relationship between Polynomial Equations.
Replies: 1   Last Post: Dec 15, 2008 8:31 AM

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 Adam Taylor Posts: 1 From: Chicago Registered: 11/19/08
Finding a relationship between Polynomial Equations.
Posted: Nov 19, 2008 6:37 PM

This requires a little explanation. I'm working on what are called Variable Air Volume boxes used to heat/cool buildings. They work by blowing air over exposed pipes and I need to determine the relationship between the heat transfer from water to air based on the amount of air flow and water flow. Based on manufacturers supplied data, I've got the following five equations:

y=-2.11E-10x^4+3.02E-7x^3-1.76E-4x^2+6.44E-2x+1.28
y=-1.87E-10x^4+2.82E-7x^3-1.71E-4x^2+6.28E-2x+1.27
y=-1.21E-10x^4+2.03E-7x^3-1.39E-4x^2+5.64E-2x+1.5
y=-1.40E-10x^4+2.20E-7x^3-1.41E-4x^2+5.39E-2x+1.56
y=-1.53E-10x^4+2.45E-7x^3-1.51E-4x^2+5.03E-2x+1.43
Where y is the amount of heat transfer and x is the amount of air flow. The equations are dependent on water flow through pipes: 3 Gallons/Minute, 2 GPM, 1.5 GPM, 1.0 GPM, and 0.5 GPM respectively.

Is there any way to use this information to determine a single equation with 3 variables? I'm not very fluent with the properties of Quartic Equations, so I can't see an obvious "divide this by this" or "raise this to this power."

Date Subject Author
12/15/08 Peter Taylor