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Commercial Geography of the Eastern British Caribbean
註釋Contents: Physical setting Economic History People Production Trade Transportation and freight rates FinanceADTTTTTTC C C CCC CCCCCC T) U (TISTW/RD) OTS price $2.60 Mathematical Sciences Corp., Pasadena, Calif. STRESS-CONCENTRATION DATA FOR INTERNALLY PERFORATED STAR GRAINS. Rept. for Nov 60-May 61, by M.E. Fourney and R.R. Parmerter. Dec 61, 24p. incl. illus. 6 refs. (NOTS TP 2728) (Contract N123(60530)25914A) (NAVWEPS rept. no. 7758) Unclassified report DESCRIPTORS: (*Solid rocket propellants, *Propellant grains, *Stresses, Tests, Test methods, Photoelasticity, Calibration.) Tests of Propellant grains with Star, Configuration. Completing preliminary work initiated by NOTS several years ago, photoelastic tests were conducted to determine the maximum tangential stress for a family of star-grain configurations in a state of plane stress. Curves are presented that give the value of the ratio of tangential stress to external pressure for web fractions from 20 to 60% for w/Rho from approximately 2 to 30 (w is the web thickness of the grain, and R HO IS THE RADIUS OF THE STAR POINT), and N (number of star points) from 3 to 8. The accuracy of the curves is estimated to be within + or - 4%. The effect of the inverse star point as investigate an found to be negligi le over a range of shapes and values of the parameter a prime/a (ratio of distances from center to the inverse star point and to the outer tar point) ROM APPROXIMATELY ZERO TO). . The experimental results c pare favorably with one theoretical calc lation. Equations are given f r extension of the data to case-bonded, internally pressurized grains and for application to problems of tangential strain. An empirical equation representing the data is appended. (Author).