Engineering topics

Piekutowski, A. J.

Publications and source records attributed to Piekutowski, A. J..

4 records

NASA NTRS2001

A New Technique for Achieving Impact Velocities Greater Than 10 km/sec

This Contractor Report describes and presents the results of work that was done in an attempt to develop an augmented acceleration technique that would launch small projectiles of known shape, mass, and state to velocities of 10 km/sec and higher. The higher velocities were to be achieved by adding a third stage to a conventional two-stage, light-gas gun and using a modified firing cycle for the third stage. The technique did not achieve the desired results and was modified for use during the development program. Since the design of the components used for the augmented-acceleration, three-stage launcher could be readily adapted for use as a three-stage launcher that used a single-stage acceleration cycle; the remainder of the contract period was spent performing test firings using the modified three-stage launcher. Work with the modified three-stage launcher, although not complete, did produce test firings in which an 0.11-g cylindrical nylon projectile was launched to a velocity of 8.65 km/sec.

Piekutowski, A. J.↗

NASA NTRS1986

Hall station and camera system operation and maintenance manual

The major components of the Hall station and camera system are described. The Hall film record of an event provides the time of flight of the projectile between the slits. A time mark generator is used to supply extremely short pulses of light at a known frequency. These pulses of light are used to produce timing marks on the edge of the film. Comparison of these marks with the spacing of the projectile images provides the information necessary to determine the time of flight of the projectile. Since the slits are installed with a known separation distance, calculation of the velocity of any object passing both slits is a simple matter.

Piekutowski, A. J.↗

NASA NTRS1980

An investigation of the cratering-induced motions occurring during the formation of bowl-shaped craters

The effects of the dynamic processes which occur during crater formation were examined using small hemispherical high-explosive charges detonated in a tank which had one wall constructed of a thick piece of clear plexiglas. Crater formation and the motions of numerous tracer particles installed in the cratering medium at the medium-wall interface were viewed through the wall of this quarter-space tank and recorded with high-speed cameras. Subsequent study and analysis of particle motions and events recorded on the film provide data needed to develop a time-sequence description of the formation of a bowl-shaped crater. Tables show the dimensions of craters produced in a quarter-space tank compared with dimensions of craters produced in normal half-space tanks. Crater growth rate summaries are also tabulated.

Piekutowski, A. J.↗

NASA NTRS1980

Formation of bowl-shaped craters

High-explosive charges are used to form, in several types of granular media, laboratory-scale examples of the bowl-shaped craters that are found to be the largest and simplest class of impact structure on planetary and lunar surfaces. High-speed films of the experiments yield crater growth rate and particle displacement data, including quantitative stress, strain, displacement, and velocity data. These results are compared with the particle displacement and velocity data from large explosion experiments which have produced bowl-shaped craters. A time-sequence description of large, bowl-shaped impact crater formation is developed from the results of these comparisons, as well as those of the morphological features and structural deformations of large explosions and impact craters.

Piekutowski, A. J.↗