Abstract:
The characterization of thermal properties continues to be a challenge facing the
development of composite phase change materials. To overcome the practical issues
of current techniques a new experimental method was developed. The system is
modelled using two fundamental models and a simplified analytical representation.
Pure myristic acid is used for validation and a performance comparison based on time,
accuracy and stability. All three approaches perform comparatively well in terms of
accuracy with an average prediction error of less than one third of a degree and all
thermal properties in line with expectations. The enthalpy model is susceptible to
instability while the effective heat capacity method does not show any such
behaviour. In addition, due to the choice of a smooth function for the transition from
liquid to solid, this method delivers more realistic behaviour. The effective heat
capacity method is faster than the enthalpy method by a factor of three, but the
analytical approach is the fastest. However for a more robust and comprehensive
representation the effective heat capacity method is preferred.
