Why discretize continuous models?

Answer 1

I hope I understand your question is related to the discretization of phenomena/ processes. The reason we do it is to get answers. I will extend a bit the question - as to why we take a continuous process/ phenomena and break it down into discrete segments, blocks, cells, etc. Some continuous processes are described by differential equations, and have general solutions. But not all processes are solvable through calculus. If we can describe a process in a discrete "control volume" at a point in time, then this can be extended to model a system with a network of cells or mesh. In doing so, we are discretizing the process in both the time and spatial dimensions. From the discretize system, time and spatial-variant responses of the system of key components of the system can be obtained through numerical methods. This is done in many of the scientific/ engineering fields, including hydrology, ecology, petroleum reservoir simulation, aeronautics and atmospherical studies. Ozone depletion and global warming models are good examples of discretized continuous systems.