Ragland taught courses in fluid dynamics, combustion and the control of air pollution. Research projects led to graduate theses on the burning rate of coal and wood particles under high convective flow, the fragmentation of coal in a fluidized bed combustor, the pressurized combustion of wood chips in a downdraft combustor for a gas turbine, modeling of deep-bed biomass combustion, and incineration of waste liquid chemicals. This research was supported by the U.S. Department of Energy, the U.S. Forest Products Laboratory and the Electric Power Research Institute. In later years, research focused on renewable energy from biomass and the associated combustion processes. Professor Ragland became chair of the Department of Mechanical Engineeringin July 1995.