Correct Answer : Complex use
Explanation : Hypersonic flow makes use of computational fluid dynamics to get accurate results because it is very inexpensive, is fast and gives straighforward results. The practical engineering problems are approximated by making some assumptions to find pressure distribution, lift drag etc. The hypersonic flow usually varies from subsonic and supersonic flow because of the presence of a thick boundary layer between the surface and thin shock wave. This cannot be solved by the conventional boundary layer methods. Hence CFD plays an important role in finding the results.
