Comsol Multiphysics Software is a complete simulation set that can be solved the differential equations by Finite Element Method (FEM) in one, two, and Three-dimensional areas. This software can be used for Electromagnetic fields, Stretching, Fluid dynamics and Gas dynamics. For the physical state, operator can use the predefined equations. It has been used for most of the phenomena in science and technology, such as: Variety of heat transfer methods, Electricity, Theory of elasticity, Molecular diffusion, Mass transfer, Propagation, Wave propagation and Fluid flow. COMSOL Multiphysics software used for design and simulate projects of Electricity, Mechanics, Geosciences, Chemistry, Pharmacy, Physics, Astronomy and Quantum. Comsol also lets operator to link to other engineering softwares such as: Catia and MATLAB. This book is suitable for students of: Chemical engineering, Petroleum engineering, Electrical engineering, Chemistry, Pharmacy and Physics.