Modeling, simulation and analysis of chemically reacting flow systems have become very important last days due to continuously increasing demand in efficient power generators ? gas turbines, power plants, internal combustion engines etc. Reducing emission of carbon dioxide, nitrogen oxides and other pollutants without significant loss of the efficiency of combustion facilities requires very sophisticated modeling and precise knowledge of governing processes of combustion. The aim of this research was to develop and implement geometrical methods for qualitative and quantitative system analysis of the combustion processes taking place in multiphase media. Combustion of a flammable spray as an auto-ignition of a cloud of fuel droplets in a hot gas and pressure driven flame - a flame propagating in a confined media were modeled and investigated. The method of singular perturbations has been used, further developed and adapted for the analysis. The results and methods present in this book would be very helpful to the researchers dealing with reacting flow modeling, asymptotic analysis and numerical simulations, to engineers and students interested in applied mathematics.