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Title	Some experiments on the effect of thermal radiation on composite rocket propellants
Publication Type	thesis
School or College	College of Engineering
Department	Chemical Engineering
Author	Mihlfeith, Carl Max
Date	1971
Description	A direct measurement was made of the dynamic response of burning solid-propellant strands to an externally imposed radiant heat flux. Burning rate changes were determined for both steady and periodic energy fluxes at atmospheric pressure. The strands were mounted at the secondary focus of an elliptical mirror system, and flux levels to 15 cal/(sec)(cm2) were obtained by use of a 5kw Xenon-Mercury lamp. Steady-state burning rates were obtained by a photographic technique, and the periodic variations in mass evolution rates were detected by measurement of the recoil force on the strands. A quartzcrystal microphone was used as a micro-force transducer. The heat flux response function, defined as (m'/rn) (F'/F) where m and F are mass rate and heat flux respectively and the prime and overbar denote perturbed and steady-state quantities, which was measured in this experiment, is closely related to the pressure, p, response function, (m'/rn) (p'/p) which is important to the combustion stability of a solid propellant in an engine. The approximate correspondence of these two response functions was demonstrated by calculations based upon current transient combustion theories. The sharp flame front model was employed for the gas phase, and the usual assumptions of a homogeneous, passive solid with energy release at / the surface and an Arrhenius type regression law were employed. Both response functions were calculated as a function of the dimensionless perturbing frequency (Q = wa/r2 where w is the radiant frequency; a the propellant thermal diffusivity and r the mean burning rate) for the same fixed parameters. At low frequencies, the response functions are essentially identical and both exhibit maxima in the response at nearly the same frequency in the range. of dimensionless frequencies of 6-50. At high frequencies, the pressure response is higher than the flux-driven response apparently because of the effect of rapidly responding gas-phase processes. For the opaque propellant, the correspondence is close enough that values of the flux-driven response are relatable to the more practically important pressure-coupled response.
Type	Text
Publisher	University of Utah
Dissertation Name	Doctor of Philosophy
Language	eng
Rights Management	© Carl Max Mihlfeith
Format	application/pdf
Format Medium	application/pdf
ARK	ark:/87278/s6bx628b
Setname	ir_etd
ID	2101272
Reference URL	https://collections.lib.utah.edu/ark:/87278/s6bx628b

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Title	Page 251
Format	application/pdf
Setname	ir_etd
ID	2101523
OCR Text	Show TABLE F-9 REFERENCES FOR APPENDIX F [1] Baer, A. D., and Ryan, by [2] Bradley, [3] Bradley, "Ignition of Composite Propellants Fluxes," AIAA J. 3 (1965), 884-889. W. H. H., and Williams, F. A. "Theory of Radiant and Hypergolic Ignition of Solid Propellants," Combustion Science and TechnoZogy 2 (1970), 41-52 H. "Theory H. of Ignition of a Reactive Solid by Energy Flux," Combustion Science and Tech Constant 2 nology [4] N. Low Radiant (1970), 11-20. Debye, P., and Bueche, E. "Scattering by an Inhomogeneous J. Solid," of Applied Phue ioe 20 (June 1969), 518-525. , [5] Duyckaerts, [6] Hair, M. G. L. Hottel, Marcel D., and Sarofin, A. H. R. Marchessault, Ohlemiller, Co., 1957. T. 876; Radiative Transfer. Ordered Systems," Interscience Ohlemiller, T. 6 p. Fuels in Princeton of Arc [12] E. New McGraw ACS Part C Publishers, 1966. 285. J., and Summerfield, Polymeric [11] Surface Chemistry. pp.53-77. H. S., Sherwood, T. K., and Reed, C. E. Applied Mathematics in Chem-ical. Engineering. JkGraw-Hill Book [10] in "Small Angle Scattering. from Partially Polymer Symposia: Mickley, 201. 1967. H., Ed. Fibrous and [9] (1959), Dekker, Inc., 1967. Hill Book Co., [8] 84 Infrared Spectroscopy York: [7] Analyst an M. Oxidizing Radiative Ignition of Gas. Report AMS No. University. "A Critical Analysis and Summerfield, M. Image Ignition of Solid Propellants," AIAA J. J., (1968), 878-886. Phototubes and Photocells. 240 RCA Technical Manual PT-60.
Reference URL	https://collections.lib.utah.edu/ark:/87278/s6bx628b/2101523