Three pipes in a vice, copper, low-carbon steel, stainless, one blowlamp, one flame. Copper doesn't just win, it isn't even the same event. This episode explains exactly why.
In this episode of The Copper Connection Podcast, Chris Bailey continues Unit 303 of the 9289 apprenticeship (ST0303), Phase 2, covering AC3.4 and AC3.5 — the three methods of heat transfer, and how the units of energy, heat and power actually relate to each other.
Chris works through conduction and the coefficient of thermal conductivity (copper at 385 W/mK against expanded polystyrene at 0.03), U values and the area × U value × temperature difference heat loss formula with a full worked cavity wall example, convection and why a hot water cylinder circulates without a pump, radiation and why a patio heater warms you but not the air, where the Joule and the watt come from, specific heat capacity and why water was chosen as the heat transfer medium, and linear expansion including why a 25 metre steel steam pipe moves over 31 millimetres once steam is flowing.
You will learn to:
Explain conduction, convection and radiation, and the hot-goes-to-cold rule underneath all three
Rank common materials by coefficient of thermal conductivity in W/mK
Calculate heat loss through a structure using area, U value and temperature difference
Explain how a hot water cylinder heats by convection, and why density drives it
Explain why radiation heats objects but not the air it travels through
Derive the Joule from force and distance, and the watt as Joules per second
Convert between watts and BTU per hour on older equipment specifications
Apply specific heat capacity values for water, ice, kerosene and propylene glycol
Calculate linear expansion for copper, steel and PVC pipework using the coefficient formula
Work through Worksheet 4 on U values and the expansion calculations before the next Unit 303 session.
heat transfer, specific heat capacity, linear expansion, unit 303 phase 2, 9289 apprenticeship, ST0303
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