Standard property names of thermodynamic model results

Introduction

ThermoContribution objects generate calculated properties that are eventually via the ThermoFrame objects exported to the client code. The following section puts some standard on the names of these properties, in particular for generic properties that can be expected to be evaluated by any thermodynamic model.

Generally, properties starting with an underscore _ are not exposed in the material objects and hence the process modelling context.

Standardized properties

The following properties shall be published under the listed names, such that downstream contributions and materials can rely on them:

Variable name	Description
_state	The canonical state of the thermodynamic model, as it may be required for derivative calculations in constrained systems.
T	Temperature
p	Pressure
n	Vector of molar quantities
S	Entropy (as the extensive quantity)
mu	Chemical potential vector

Standard property suffixes

Some of the above properties that are updated from one contribution to another (e.g. S, mu), can be frozen in various states with below suffixes.

Variable name	Description
*_std	Standard state properties
*_im	Ideal mix properties
*_ig	Ideal gas properties
*_res	Residual property
*_ex	Excess property

Optionally, a model can export second order properties, for which the physical interpretation is dependent on the coordinate system:

Variable name	Description
dSdT	Temperature derivative of entropy at constant pressure
dVdT	Isobaric expansion
dVdp	Isothermal compression
s_bar	Partial molar entropies (vector)
v_bar	Partial molar volumes (vector)