In the recent past, there has been an advanced concern in solving nonlinear partial and ordinary differential equations associated with Mathematical models. Several industries such as Engineering and Technological industries encountered nonlinear boundary-value problems that cannot be treated easily by analytical methods. In the field of fluid mechanics and its allied subjects, despite remarkable progress made in improving new and powerful tools for solving the boundary-value problems constituted because of these fields, still much remains to be done. The highlight of the Book is to study the effect of non-dimensional parameters arising in the mathematical modeling of the physical problem on the flow and heat transfer under different physical situations. This book can help the reader to understand the Mathematical models of fluid flow through different geometries and the toolset needed to treat them, namely numerical and analytical techniques such as the Kellerbox method and Optimal Homotopy Analysis Method (OHAM).