Most of engineering problems, especially heat transfer equations, are nonlinear, therefore some of them are solved using numerical solution and some are solved using different semi-analytic methods. There are several new semi-analytical methods, including homotopy perturbation method (HPM), Parameter perturbation method (PPM), Differential Transformation Method (DTM), hybrid differential transformation-finite difference (Hybrid-DTM), Adomian decomposition method (ADM), Homotopy Analysis Method (HAM), and Galerkin Optimal Homotopy Asymptotic Method (GOHAM). These methods can solve a large class of nonlinear problems efficiently, accurately and easily. In this book, semi-analytical methods are applied to solve a range of engineering problems. After the various methods are introduced, their application in nanofluid flow and heat transfer, magnetohydrodynamic flow, electrohydrodynamic flow and heat transfer, and nanofluid flow in porous media within several examples are explored. This will be a valuable reference resource for materials scientists and engineers, and will help familiarize them with a wide range of semi-analytical methods, and how they are used in nanofluid flow and heat transfer. The book also includes case studies to illustrate how these methods are used in practice. Readers will gain complete familiarity with governing equations where nanofluid is used as working fluid Readers will gain a thorough understanding of the fundamentals in new analytical methods in solving to the applications of nanofluid flow and heat transfer in presence of magnetic and electric field Gives a detailed overview of nanofluid motion in porous media.