WEBVTT

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A cool surface can hide a hotter

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core centre.

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Heat moves more easily along each sheet

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than across the coated stack.

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A larger limb makes the escape path

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longer.

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Compare equal lengths of circular limbs,

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with the same loss per unit volume.

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Double the diameter:

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heat generation becomes four times greater,

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but the side surface only doubles.

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Cooling ducts split the stack into thinner

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packets, bringing oil closer to the interior.

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Spacers must keep those ducts open after

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clamping, without concentrating pressure.

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Each duct also removes space available for

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steel.

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Duct positions, flow paths and net steel

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section must therefore be designed together.

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A surface reading alone cannot establish the

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centre temperature.