# 2.12. Version 5.6 (2022/04/18)

New Features

  - Added support for variable solidus and liquidus temperatures in melting sources and electrochemistry.

  - Added support for multi-dimensional structured tables to generic models

  - Added support for universal aria expressions

  - Added time step (`dt`) as a standard global variable, available to use in global functions.

  - Improved the Generalized_Rad and Generalized_Nat_Conv models to allow in-line specification of constants or string functions for h and Tref.

  - Improved performance of simulations using chemeq with dynamic rebalance. Specifically, the default single weight criteria per equation system used by the graph partitioner was split into several weight criteria (`CHEMEQ`, `ASSEMBLY`, `LINEAR_SOLVE`, `DEFAULT`) resulting in better load balancing.

  - Increased the maximum number of variables allowed in a string function to 50 variables.

  - Stability improvements for Sparc-Aria aerothermal coupling.

  - Added native implementation of (micromechanics pressurization) MMP modeling within Aria. This model incorporates decomposition/thermal expansion of pores and tracks material permeability within explosive materials using native expressions. This model is based off of the work done by Hobbs et al. [2].

Convention Change

  - Updated sign convention for residual-based post-processors to be consistent with expression-based post-processors and aria flux specifications (positive = outflux)