# 10.3: Heat Transfer Simulation

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Here we demonstrate how heat transfer through the mould wall determines the temperature change in a casting during solidification. The simulation assumes Newtonian cooling where heat transfer is limited by the interface between the metal and the mould.

The simulation shows the effect of varying parameters such as the interfacial heat transfer coefficient, h, the casting length, L and the amount of superheat (determined by the pouring temperature, Tp). It can be carried out for a wide range of metals to study the effect of properties such melting temperature Tm, latent heat of fusion per unit volume, ΔHf,V, thermal conductivity, K and heat capacity per unit volume, Cp,V. Click here to see how the heat capacity per unit volume is related to specific heats measured relative to other amounts.

The relevant thermal properties of several pure metals are shown below

Melting temperature
Latent Heat of fusion
Volumetric Heat capacity
Thermal conductivity
K
MJ m-3
kJ m-3 K-1
W m-1 K-1
Ag
1235
1100
2920
422
Au
1337
1200
2800
272
Al
933
1070
3100
240
Cu
1358
1842
4080
395
Mg
922
640
2240
154
Pb
601
260
1590
34
Sn
505
440
1780
63
Zn
693
812
3070
112

In the simulation you can select any of these materials and its properties will be displayed. You may then vary parameters such as the casting length, the interfacial heat transfer coefficient between the solid and the mould wall and the pouring temperature in order to see how long it takes for the casting to solidify and cool.

There are a couple of provisos: Firstly because this is a Newtonian cooling simulation you must ensure that the Biot number is low enough for this assumption to be valid (hence for the metals which have poor thermal conductivities, you must keep the casting length relatively low). Secondly, of course, you must ensure that the metal is poured above its melting temperature!

There are a number of assumptions and simplifications we are making in this simulation which may not be the case for a real casting.

This page titled 10.3: Heat Transfer Simulation is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Dissemination of IT for the Promotion of Materials Science (DoITPoMS).