WEBVTT

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A cool surface can hide a

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hotter core centre.

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Heat moves more
easily along each

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sheet than across
the coated stack.

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A larger limb
makes the escape

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path longer.

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Compare equal lengths
of circular limbs,

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with the same loss per unit

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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

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thinner packets,
bringing oil closer to

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the interior.

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Spacers must keep
those ducts open

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after clamping,
without concentrating

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pressure.

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Each duct also removes
space available

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for steel.

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Duct positions,
flow paths and net

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steel section must
therefore be designed

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together.

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A surface reading
alone cannot establish

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the centre temperature.