The first 20 years of Miles' research was devoted to electrical and aeronautical engineering. He turned his mathematical abilities to geophysical fluid dynamics when he joined Scripps, and made numerous contributions to many aspects of fluid dynamics, including supersonic flow, ocean tides, the stability of currents and water waves and their nonlinear interactions, as well as extensive work in the application of mathematical methods.
Throughout his career, he wrote more than 400 publications. He has the unique distinction of being one of the few fluid mechanics researchers to have published more than hundred scientific research articles (117) in Journal of Fluid Mechanics.[2]