Masters Theses
Date of Award
12-1987
Degree Type
Thesis
Degree Name
Master of Science
Major
Mechanical Engineering
Major Professor
Roy J. Schulz
Committee Members
R. L. Young, Virgil K. Smith
Abstract
An analytical investigation was conducted into the heat transfer and erosive environment experienced along the inner wall of rocket exhaust diffusers during altitude tests of full scale solid rocket motors. The purpose of this effort was to provide a validated analytical tool which is applicable to full scale testing, and to use the tool to perform parametric studies concerning the survivability of existing and future exhaust rocket diffuser designs. An existing system of computer codes were acquired, validated, and adapted to the full scale test requirement, based upon the validation results. Model adaptations required during the current validation effort included: 1) implementation of an optically-thick plume radiation model, 2) elimination of the particle thermal heat transfer mechanism from the model, and 3) adjustment of the accommodation coefficients which apply to particle impact heat transfer. The adapted model was successfully validated against an existing experimental data base obtained during full scale solid rocket motor altitude tests and by comparison to one-dimensional theory, where appropriate.
Following the validation effort, parametric studies were conducted considering several variables of practical interest in typical solid rocket motor altitude tests. These variables were: 1) rocket diffuser inlet geometry, 2) rocket motor nozzle geometry, 3) rocket motor propellant formulation, 4) test facility scale, 5) ambient pressure, and 6) rocket motor thrust level. The parametric study showed that, of the parameters investigated, the diffuser heating and erosion is most sensitive to rocket motor nozzle geometry variations and rocket exhaust diffuser inlet angle variations, because of the influence of the solid particle impact contribution to heat transfer and erosion. The effects of facility ambient pressure, motor thrust level, and facility scale were also significant, particularly in the zone of rocket motor plume impingement on the diffuser inner wall. The effect of propellant formulation was insignificant for the narrow variation of propellant formulations investigated.
Recommended Citation
Jordan, John Lee, "Altitude test cell rocket diffuser heat transfer and erosive environment modeling. " Master's Thesis, University of Tennessee, 1987.
https://trace.tennessee.edu/utk_gradthes/13503