The use of computational fluid dynamics (CFD) tools by the aerospace field to increase understanding of fluid dynamics and aerodynamic phenomena has been increasing rapidly during the last decade, especially in recent years. The main reasons for this are the fast-growing simulation capabilities in the CFD field and the rapid expansion of capabilities in computer hardware performance. For example, the speed of execution of computer hardware has increased by a factor of about 15 in the last decade and by more than 200 during the last two decades. This rapid advance in computational execution speed. The upper curve shows how the theoretical peak execution speed has improved over time and includes effects of both circuit velocity and architectural improvements, eg Vectorization of Cray computers. The lower curve represents the improvement in the speed of execution due to the speed of the circuit. The average curve represents the actual improvement in execution speed performance of a variety of CFD application codes as approximated from the shaded symbols.