An Experimental Investigation of the Pressure and Velocity Profiles in a Spinning, Cold-flow Rocket Motor

Abstract : The investigation was divided into two phases: (1) the selection and calibration of a suitable probe and (2) pressure and velocity measurements within the chamber of the cold-flow apparatus. A five-port impact tube probe was selected and calibrated. The three-dimensional calibration scheme employed for the subject investigation did not require the probe to be rotated once positioned within the rocket motor chamber. Experiments were conducted in the rocket motor chamber when a 1.125 inch throat diameter nozzle and a 2.0 inch throat diameter nozzle were employed. Pressure and velocity profiles were measured at two longitudinal locations within the chamber for rotational speeds of 1000, 3000 and 5000 rpm. The measured axial and tangential velocity profiles were compared with the predicted axial and tangential velocity profiles which were based upon a uniform axial velocity injection and a solid body vortex.