Heat transfer is fundamentally described as the energy in transit due to temperature difference. Heat transfer calculations in various facets of engineering applications are significant to aid engineering design of heat exchanging apparatus. Reducing computational time is a demanding task faced by researchers and users. The book discusses the calculation procedure in some application fields, such as differential evaluation of heat recoveries with CFD in a tube bank, heating and ventilation of equipment, and methods for analytical solution of nonlinear problems. Numerical evaluation is the prerequisite for design and manufacture of heat exchanging tools. Numerical and experimental knowledge, as well as the analytical solution of heat transfer is also discussed. Furthermore, the book elaborates on the study of heat transfer phenomenon and its applications.