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SECONDARY MISSILES GENERATED BY NUCLEAR-PRODUCED BLAST WAVES

Description: The generation of secondary missiles by blast waves was investigated in Operation Plumbbob for three nuclear detonations with estimated yields of 11, 38, and 44.5 kt. A trapping technique was used to determine the impact velocities for 17,524 missiles (stones, glass fragments, spheres, and military debris or steel fragments) which occurred in open areas, houses, and an underground shelter with an open entryway. The equivalent ideal-wave peak overpressures computed from measured blast data for the open-area stations varied from 3.8 to 21 psi. Two houses and an underground shelter were located where the overpressures were 3.8 and 65 psi, respectively. The effect of hill-and-dale terrain on the production of missiles was investigated on one of the shots. Precursor effects were noted on two of the shots at stations near Ground Zero. Missile velocities measured at all stations except the underground shelter were compared with those computed by use of a model based on an ideal blast wave. An analytical procedure was presented by which translational velocities of nmn can be estimated using the measured velocities of spheres and stones. Total distances of displacement were measured for 145 stones that weighed up to 20 kg and for 1528 fragments from a concrete-block wall. (auth)
Date: February 1, 1962
Creator: Bowen, I.G.; Franklin, M.E.; Fletcher, E.R. & Albright, R.W.
Partner: UNT Libraries Government Documents Department

A MODEL DESIGNED TO PREDICT THE MOTION OF OBJECTS TRANSLATED BY CLASSICAL BLAST WAVES

Description: BS>A theoretical model was developed for the purpose of predicting the motion of objects translated by winds associated with "classical" blast waves produced by explosions. Among the factors omitted from the model for the sake of simplicity were gravity and the friction that may occur between the displaced object and the surface upon which it iritially rested. Numerical solutions were obtained (up to the time when maximum missile velocity occurs) in terms of dimensionless quantities to facilitate application to specific blast situations. The results were computed within arbitrarily chosen limits for blast waves with shock strengths from 0.068 to 1.7 atm (1 to 25 psi at sea level) for displaced objects with aerodynamic characteristics ranging from those of a human being to those of 10-mg stones and for weapon yields at least as small as 1 kt or as large- as 20 Mt. (auth)
Date: January 1, 1961
Creator: Bowen, I.G.; Albright, R.W.; Fletcher, E.R. & White, C.S.
Partner: UNT Libraries Government Documents Department

TERTIARY EFFECTS OF BLAST--DISPLACEMENT

Description: Thc objective of the project was to determine the velocity-time and distance-time histories of anthropomorphic dummies and equivalent spheres (idealized models having an acceleration coefficient alpha equal to that of the dummy) displaced by blast winds. The dummies and spheres were located at stations within regions of about 5 and 7 psi overpressures. The technique used for recording the movement of these objects was phototriangulation. Analysis of the films obtained gave the ond shot the field of veiw was obscured by smoke (perhaps dust too) before any motion could be recorded by the cameras. In one phase of the experiment, equivalent spheres were caught in flight at near predicted maximum velocity by missile traps. The depth of sphere penetration in the calibrated capture medium was then used to compute the sphere velocity. (auth)
Date: February 1, 1959
Creator: Taborelli, R.V.; Bowen, I.G. & Fletcher, E.R.
Partner: UNT Libraries Government Documents Department

DETERMINATION OF AERODYNAMIC DRAG PARAMETERS OF SMALL IRREGULAR OBJECTS BY MEANS OF DROP TESTS

Description: Drag coefficients were determined for various irregular objects such as glass fragments, stones, steel fragments, and spheres by means of drop tests for use in a mathematical model to correlate nuclear explosion blast experiments. Drop tests were also made on small laboratory animals and extrapolated to estimate the drag properties of man. A method was developed to estimate the average drag properties of man from his total surface area. (D.L.C.)
Date: June 1, 1960
Creator: Fletcher, E.R.; Albright, R.W.; Goldizen, V.C. & Bowen, I.G.
Partner: UNT Libraries Government Documents Department

Biologic response to complex blast waves

Description: Small, bare charges were detonated inside an M59 armored personnel carrier (APC) in an attempt to simulate the complex blast waves generated by the jets from shaped-charge warheads penetrating into armored vehicles. Anesthetized sheep were placed inside the APC at 92- and 122-cm ranges from 57- or 113-g pentolite charges. Pressure-time was measured by pressure transducers either mounted on the animals or free standing at comparable ranges on the opposite side of the vehicle. In general, the waveforms were characterized by an initial shock wave of less than 1-msec duration followed by repeated reflections of decreasing magnitude. No deaths nor lung hemorrhages were observed, but all the animals sustained severe ear injury. Animals subjected to peak overpressures of 1.2 to 2.3 bar from the 113-g explosions also received slight non-auditory blast injuries to the upper respiratory and gastrointestinal tracts; those exposed to peak overpressures of just under 1 bar from the 57-g charges did not. The non-auditory blast injuries inside the APC were more severe than those sustained by sheep at comparable distances from 113-g charges in the open. The results suggested that the biological consequences of a complex wave of the type encountered in this study can be equated approximately to a Friedlander wave with a peak overpressure equal to that of the complex wave and with a total impulse equal to the impulse over the first 2 to 3 msec of the complex wave. 9 refs., 7 figs., 1 tab.
Date: January 1, 1985
Creator: Richmond, D.R.; Yelverton, J.T.; Fletcher, E.R. & Phillips, Y.Y.
Partner: UNT Libraries Government Documents Department

NUCLEAR BOMB EFFECTS COMPUTER, (INCLUDING SLIDE-RULE DESIGN AND CURVE FITS FOR WEAPONS EFFECTS)

Description: S>Based on data from the 1962 edition of The Effects of Nuclear Weapons, a circular slide rule was designed to evaluate 28 different effects of nuclear weapons. Of these 28 different effects, 13 relate to blast, 5 to thermal radiation, 1 to initial nuclear radiation, 2 to early fallout, 6 to crater dimensions, and 1 to fireball dimensions. Most of the parameters are presented as functions of range and yield (1 kt to 20 Mt). Techniques are described which make it possible to estimate most of the effects parameters for yields greater than 20 Mt or smaller than 1 kt. The report presents curve fits of weapons- effects data, design analysis for the slide rule, and instructions for use of the rule along with some of the implications of the data in regard to biological and structural damage. The machine techniques are mentioned which were used to prepare the original graphs necessary for the production of the slide rule. (auth)
Date: April 1, 1962
Creator: Fletcher, E.R.; Albright, R.W.; Perret, R.F.D.; Franklin, M.E.; Bowen, I.G. & White, C.S.
Partner: UNT Libraries Government Documents Department