The paper describes a universally structured simulation platform which is used for the analysis and prediction of combustion in compression ignition (CI) engines. The models are on a zero-dimensional crank angle resolved basis as commonly used for engine cycle simulations. This platform represents a kind of thermodynamic framework which can be linked to single and multi zone combustion models. It is mainly used as work environment for the development and testing of new models which thereafter are implemented to other codes.One recent development task focused on a multi zone combustion model which corresponds to the approach of Hiroyasu. This model was taken from literature, extended with additional features described in this paper, and implemented into the thermodynamic simulation platform. Within this environment the models were systematically assessed by analysis and identification of the mechanisms which predominantly control the combustion process and the formation of NO and Soot. Due to the flexibility of the simulation platform the multi zone model could be directly compared with a conventional 2-zone model.For the assessment a systematic procedure was developed which clearly depicts the advantages of the multi zone approach. The assessment also resulted in identified model parameters. In applying them to measurements of three different engines, the quality of the models (multi-zone vs. 2-zone) is demonstrated and discussed.