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3 Formulas of Heat Transfer
Heat transfer and flow processes occur in the majority of polymer processing machinery
and often determine the production rate. Designing and optimizing machine elements
and processes therefore require knowledge of the fundamentals of these phenomena.
The flow behavior of polymer melts has been dealt with in Chapter 2. In the present
chapter, the principles of heat transfer relevant to polymer processing are treated and
explained with examples.
3.1 Steady State Conduction
Fourier's law for one-dimensional conduction is given by
where
Q = heat flow thermal conductivity
A — area perpendicular to the direction of heat flow
T = temperature
x = distance (Figure 3.1)
Figure 3.1 Plane wall [1]
3.1.1 Plane Wall
Temperature profile (Figure 3.1) [I]:
Heat flow:
(3.1)
(3.2)
(3.3)