Concepts, Capabilities, and Limitations of Global Models: A Review

For researchers wishing to generate an understanding of complex plasma systems, global models often present an attractive first step, mainly due to their ease of development and use. These volume averaged models are able to give descriptions of plasmas with complex chemical kinetics, and without the computationally intensive numerical methods required for spatially resolved models. This paper gives a tutorial on global modeling, including development and techniques, and provides a discussion on the issues and pitfalls that researchers should be aware of. Further discussion is provided in the form of two reviews on methods of extending global modeling techniques to encompass variations in either time or space. A discussion of global modeling development and techniques is given, aimed at researchers wishing to use or create a global model of a plasma system. Emphasis is given to issues that may arise and pitfalls that should be considered, in particular with regards to accuracy of any results. Further discussion is given on extensions that are able to include variations in either space or time.