This book presents a detailed numerical study of various boundary layer free convective flow problems including nanofluid flows. The complete details of a robust, well-tested, implicit finite-difference numerical method to solve the governing boundary-layer coupled non-linear system of partial differential equations are presented. The influence of the significant parameters on the velocity field, temperature field, concentration field, skin friction coefficient, Nusselt number and the Sherwood number are extensively discussed with the help of graphs and tables. It is hoped that this book will be useful for the researchers who are working on the solution of partial differential equations governing fluid dynamics and heat and mass transfer problems.