Wave rotor charging process - Effects of gradual opening and rotation

Abstract

The wave rotor charging process under conditions of gradual opening accompanied by passage rotation is numerically simulated. Insights into the response of the interface and kinematics of the flowfield to various opening times are given. Since the opening time is inversely proportional to the rotational speed of the rotor, effects of passage rotation such as centripetal and Coriolis accelerations are intrinsically coupled to the gradual opening process. Certain three-dimensional features associated with the charging process as a result of centripetal and Coriolis accelerations are illustrated. It is shown that the interface between driver and driven gas acquires a three-dimensio nal distortion depending on the rotational speed and opening time. Nomenclature a = speed of sound B = dimensionless ratio of time scales E = total energy per unit mass e = unit vector h,R = rothalpy L = passage length Mo, Mn = wheel Mach number based on tip radius and a reference speed of sound p = pressure RH = hub radius RT = tip radius RU = rotation parameter T = temperature t = time w = relative velocity vector y = ratio of specific heats 6 = azimuthal coordinate in a stationary reference frame 6' = azimuthal coordinate on the rotating passage p = density T = reference time scale 4> = passage sector angle ft = rotational speed Subscripts