Study of heat transfer coefficient in helical coil
changes from 521 W·m-2·K-1 to 684 W·m-2·K-1. As seen, when comparing the highest and the
lowest agitation rates, the trend is evident.
On the following graph (Figure 10) it is shown that in reality there was some heat loss through
the bath walls, therefore another way to calculate the global heat transfer coefficient was used.
f(x) = NaN ln(x) 250
R² = NaN
200
150
Q lost (W)
1342100
rpm Logarithmic (1342 rpm) 618 rpm
50
0
0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000
time (s)
Figure 10: Bath heat loss
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