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Shape factor Se from Equation 5.91:
Reynolds number of water:
Using Equation 5.92 for the heat transfer coefficient a
From Equation 5.90 we get for the heat received by the cooling water Qw
Cooling time tK from Equation 3.41:
From the heat balance
we obtain by iteration
Tw = 37.83 0 C
Finally, the cooling time tK with Tw = 37.83 is from Equation 3.41
tK = 8.03 s
The influence of the cooling channel lay out on cooling time can be simulated on the
basis of the equations given by changing the distances x and y (Figure 5.45) as shown
in Figure 5.46 and Figure 5.47. The effects of the temperature of cooling water and of
its velocity are presented in Figure 5.48 and Figure 5.49, respectively. From these results
it follows that the cooling time is significantly determined by the cooling channel lay
out.