Reacting heterogeneous cloud

Summary

New reacting heterogeneous cloud, solver and tutorial. This cloud is formed of pure solid particles which reacts with the carrier phase. It is derived from reacting cloud.

Resolved bugs (If applicable)

(Links to issues)

Details of new models (If applicable)

The only available reacting heterogeneous model is Heteregeneous noncatalytic reaction MUCS approach.

Reference: D. Papanastassiou and G. Bitsianes, Modelling of Heterogeneous Gas- Solid Reactions, Metallurgical Transsactions, 480. Volume 4. 1973

Risks

(Possible regressions?) (Changes to user inputs?)