Wood heat capacity

chemics.wood_heat_capacity.cp_wood(x, tk)[source]

Heat capacity of wood based on moisture content and temperature

\[c_{p,x} = \left(c_{p0} + c_{pw} \frac{x}{100}\right) / \left(1 + \frac{x}{100}\right) + A_c\]

where \(c_{p,x}\) is heat capacity of wet wood [kJ/(kg K)], \(c_{p0}\) is heat capacity of dry wood [kJ/(kg K)], \(c_{pw}\) is heat capacity of water as 4.18 kJ/(kg K), \(x\) is moisture content [%], and \(Ac\) is an adjustment factor that accounts for the additional energy in the wood–water bond 1.

The \(c_{p0}\) term is determined from

\[c_{p0} = 0.1031 + 0.003867\,T\]

where \(T\) is temperature [K]. The \(A_c\) term is calculated from

\[A_c = x (b_1 + b_2 T + b_3 x)\]

with \(b_1 = -0.06191\), \(b_2 = 2.36e\times10^{-4}\), and \(b_3 = -1.33\times10^{-4}\).

Parameters
  • x (float) – Moisture content [%]

  • tk (float) – Temperature [K]

Returns

cp (float) – Heat capacity of wood [kJ/(kg K)]

Example

>>> cp_wood(12, 340)
1.91

References

1

Samuel V. Glass and Samuel L. Zelinka. Moisture Relations and Physical Properties of Wood. Ch. 4 in Wood Handbook, pp. 1-19, 2010.