Issue 10 Volume 41 May 16, 2003

edge of the hole. The results of the analyses show that the predicted initial crack lengths compared well with the experimental
measurements.
DTIC
Cracks; Crack Propagation; Solid Propellants; Strain Rate; Holes (Mechanics); Structural Analysis
20030032977 Brookhaven National Lab., Upton, NY
Creating an ‘Electromagnetic Interference Risk Distribution Map’ In the Modern Hospital
Spyropoulos, B.; Glotsos, D.; Batistatos, D.; Marneris, I.; Oct 2001; 5 pp.; In English; Original contains color illustrations
Report No.(s): AD-A410469; No Copyright; Avail: CASI; A01, Hardcopy
Electromagnetic Interference (EMI) from various sources can cause medical monitoring equipment and other hospital
devices to malfunction, that can range from mere inconvenience to serious problems. Comprehensive induced Magnetic Field
and Real Electromotive Force measurements have been carried out and properly documented in the form of an ‘on line risk
distribution map’ covering all departments in the General District Anti-Cancer Hospital of Piraeus ‘Metaxa’.
DTIC
Electromagnetic Interference; Medical Equipment
20030033000 Air Force Research Lab., Edwards AFB, CA, USA
The Effects of Pressure on Fracture of a Rubbery Particulate Composite
Miller, T. C.; Liu, C. T.; Jun. 2000; 18 pp.; In English
Contract(s)/Grant(s): Proj-2302
Report No.(s): AD-A410517; AFRL-PR-ED-TP-2000-044; No Copyright; Avail: CASI; A03, Hardcopy
There is a need for studying the effects of pressure on fractures. Recommendations for future work: examination of short
crack fracture phenomena (why do short cracks behave differently?) Surface crack growth analysis: find a way to measure
crack depth and width in pressurized environment. Links between microstructure and pressure effect (establish a connection
between pressure effect and microstructural phenomena such as void nucleation, growth, and coalescence).
DTIC
Crack Propagation; Fracture Mechanics; Pressure Effects
20030033023 Virginia Polytechnic Inst. and State Univ., Blacksburg, VA
Stress Intensity Factors and Paths for Cracks in Photoelastic Motor Grain Models Under Internal Pressure
Smith, C. W.; Constantinescu, D. M.; Liu, C. T.; April 20, 2001; 11 pp.; In English
Contract(s)/Grant(s): AF Proj. 2302
Report No.(s): AD-A410574; AFRL-PR-ED-TP-2001-100; No Copyright; Avail: CASI; A03, Hardcopy
Computational analysis and two-dimensional tensile tests on single motor grain fins suggest that cracks in fin tips are most
likely to originate at the coalescence of a fin end tip radius, with a small radius from the side of the fin. Some manufacturers
have also noticed defects formed during casting at the fin tip on the fin axis. The following is an experimental investigation
utilizing frozen stress photoelastic models of an existing motor grain geometry in order to clarify stress intensity factor (SIF)
values and crack growth paths for cracks emanating from the two above- noted potential critical loci. Comparisons between
results from cracks grown from the two loci will be made, suggesting interesting conclusions.
DTIC
Crack Propagation; Rocket Engines; Internal Pressure; Stress Intensity Factors; Photoelasticity
20030034597 Air Force Research Lab., Edwards AFB, CA, USA
Crack Growth Rates in a Propellant Under Various Conditions
Miller, Tim; March 27, 2001; 18 pp.; In English
Report No.(s): AD-A410423; AFRL-PR-ED-VG-2001-053; No Copyright; Avail: CASI; A03, Hardcopy
Cracks develop during manufacturing, handling and storage of rubbery particulate composites. During the service life, the
cracks may begin to grow, but may still be subcritical because the cracks may grow slower than the burn rate of the propellant.
Results for three types of specimens are described. This is done both at ambient and 1000 psi (6895 kPa) pressure.
DTIC
Crack Propagation; Manufacturing; Pressure Dependence; Rocket Propellants
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