An example of the results is shown in Figure 3.1.12 above and the following conclusions can be
formulated:
x Circumferential velocity of the cooled roll is influencing the heat transfer achieved from spray
nozzles.
22
x Both the maximum values of HTC and the shape of the HTC distribution are influenced by the
roll velocity.
x Cooling intensity decreases with the increase of velocity.
x The sensitivity of cooling intensity to the roll velocity can be observed in all surface
temperature intervals.
x Heat transfer coefficients at high roll velocities are the most sensitive to the surface
temperature.
x The influence of the centrifugal forces is an important factor because the coolant is removed
quickly from the roll when it is rotating at higher velocity.