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Titles and Abstracts for Issue No. 16, Winter 2002
- Evaluation of the Hazards
Posed by High Energy Bangers Part 2. Damage to Hand Simulants
- R. K. Wharton and A. E. Jeffcock [Health
and Safety Laboratory, Harpur Hill, Buxton, UK]
- Abstract: This paper reports the development and construction of hand simulant models
and their use to evaluate the extent of injury to persons holding, or
being near to, high energy bangers when they are initiated.
The test work suggests a risk of severe injury to the hand and wrist from flashbangers containing more than 1 g of compositon, with amputation of the hand being possible for the more powerful items.
- Keywords: potassium perchlorate,
barium nitrate, aluminium, flash composition, bangers, damage, firecracker,
small salute
- Reprint
Information: Number of pages = 4.
- Thermodynamic Modeling
of High-Temperature Systems
- Gleb V. Belov [Glushko
Thermocentre, IHED, IVTAN Assoc. of RAS, Izhorskaya 13/19, Moscow, Russian
Federation]
- Abstract: An outline of thermodynamic modeling of high-temperature systems
is presented, including a historical introduction. There is no intention
to provide a complete history of thermodynamic modeling, so neither vapor-liquid
equilibria nor the thermodynamics of non-ideal solutions is discussed.
This article reflects the author’s personal vision of the state of the
art.
- Keywords: thermodynamics, modeling,
equilibria
- Reprint
Information: Number of pages = 8.
- Test Burn of a Temporary
Fireworks Stand
- David Lynam [Clark
County Fire Marshal, Ridgefield, WA, 98642, USA]
- Abstract: In 1997, a burn test was performed on a temporary retail fireworks stand
stocked with 900 pounds (400 kg) of a range of consumer fireworks. A maximum
interior temperature of 1,400 °C was recorded inside the test stand and
flashover occurred within approximately one minute of involvement of the
fireworks. Ignited fireworks were observed traveling more than 250 feet
(75 m) beyond the stand’s partially open front side. The greatest heat
flux [calculated to be 60 kW/m2 at a distance of 5 feet (1.5 m)] was also
observed on the stand’s front side. It was concluded that a setback distance
of 20 feet (6 m) was required on sides of the stand without openings,
and that a setback distance of 40 feet (12 m) was required where there
were large openings in the stand.
- Keywords: fireworks stand, consumer
fireworks, test burn, flashover, heat flux, setback distance
- Reprint
Information: Number of pages = 14.
- Accidents and their
Role in Aiding the Management of Health and Safety in Pyrotechnics Manufacture
- Allen Webb [Health
and Safety Executive, Merton House, Bootle, UK]
- Abstract: The investigation and analysis of the causes and circumstances of accidents
can be an invaluable tool in assessing the effectiveness of systems for
the management of health and safety. This article considers and draws
on the lessons learned from a number of accidents to suggest a general
framework to aid the development of management systems for the manufacture
of explosives. While the emphasis is on firework and pyrotechnic manufacture,
the issues have wider application.
- Keywords: safety management,
pyrotechnics, health and safety, manufacture
- Reprint
Information: Number of pages = 10.
- Thermodynamics of Black
Powder and Aerodynamics of Propelled Aerial Shells
- John E. Mercer [Gig
Harbor, WA, USA]
- Abstract: This paper describes the theoretical basis of a computer code that numerically
models firework mortars. The code analyzes both the Black Powder propelling
and flight segments of a shell. Equations for the gas dynamics of Black
Powder combustion, leakage flow around the shell and aerodynamics of flight
are included. Representations for commonly used Black Powder grain sizes
allow for simple modeling of test cases. The numerical equation solver
in the code uses standard parameters for specifying any mortar test condition.
This solver computes every model parameter of the gas and shell dynamics
in 2 µs time steps while in the mortar and in 1 ms time steps in flight.
The modeling demonstrates that the release of energy from Black Powder
is a multi-step process, first from the burning of the grains, next from
the latent heat release from condensation, and finally from the latent
heat release from fusion. The shell flight dynamics are based on aerodynamic
theory employing conventional parameters. Uses of this code include design
of mortars, and parametric and safety analyses. The code even includes
a crosswind drift analysis for predicting expected dud fallout location.
The analytic models were verified on a multitude of test cases, taken
from both firework mortars and muzzle loading firearms data. Agreement
with the experimental data is within the experimental measurement variation.
- Keywords: black powder, aerial
shells, thermodynamics
- Reprint
Information: Number of pages = 16.
- Effect of Ultrasound
on Single-Base Propellants for Pyrotechnic Purposes
- Valentin Grozev [Artillery
and Air Defense Military Academy, Shoumen, Bulgaria], Radi
Ganev [Ministry of Defence, Armament
Policy Directorate, Sofia, Bulgaria], and Ivan
Glavchev [University of Chemical Technology
and Metallurgy, Sofia, Bulgaria]
- Abstract: Investigations were conducted on the effect of ultrasound on single-base
propellants. Changes in the average viscosimetric molecular weight of
nitrocellulose in the solutions of propellants in acetone and in a mixture
of ethyl alcohol-diethyl ether were studied. It has been established that,
for at least 60 minutes, the molecular weight decreases exponentially.
On-going degradation processes and the effect of cavitation during treatment
of the propellants with ultrasound were analyzed. The change in nitrogen
content and the heat released were also measured. The absorption coefficients
and the sound velocities of the propellants were determined. Using these
parameters, the dynamic modulus of elasticity was calculated. The results
obtained are used in the processing of propellants for pyrotechnic purposes.
- Keywords: single-base, propellants,
ultrasound, degradation
- Reprint
Information: Number of pages = 6.
- The Effects of External
Fire on Fireworks Stored in Steel ISO Transport Containers
- S. G. Myatt [Health
and Safety Laboratory, Harpur Hill, Buxton, Derbyshire, UK]
- Abstract: The increased use of steel ISO transport containers for storing fireworks
led the UK’s Health and Safety Executive (HSE) to commission research
to gain a better understanding of the behaviour of fireworks in such storage
when exposed to an external fire. Subsequent incidents involving storage
of fireworks in ISO containers demonstrated that violent explosions could
occur. This added impetus to the research programme. It was found that
selection boxes of fireworks that were readily available to the general
public were unlikely to present a significant hazard in bulk storage.
More energetic fireworks, such as those used by professional display operators,
were capable of generating sufficient pressure within the container to
cause the doors to fail and for the walls and roof to become deformed.
These more energetic trials used a range of firework types including star
shells up to 200 mm in diameter, and resulted in unburnt stars being projected
up to 140 m and unexploded fireworks being thrown to a distance of up
to 32 m. Pyrotechnic effects (stars) were observed over an area in excess
of 100 m diameter and thermal imaging indicated that a fireball with an
effective surface temperature of 400 °C was produced over a diameter of
36 m. None of the trials produced violent mass explosion effects of the
type reported in connection with recent incidents at Uffculme, UK and
Enschede, The Netherlands.
- Keywords: fireworks, storage,
fire, explosion, ISO, container, classification, UN
- Reprint
Information: Number of pages = 12.
- Application of Hydroxyl
(OH) Radical Ultraviolet Absorption Spectroscopy to Rocket Plumes
- M. W. Teague, Tonya Felix [Department
of Chemistry, HendrixCollege, Conway, AR, USA] M.
K. Hudson and R. Shanks [Dept. of Applied
Science, University of Arkansas at Little Rock, Little Rock, AR, USA]
- Abstract: A
spectrometer system was constructed for measurement of transient species
in flames by absorption of ultraviolet radiation. The output of a xenon
arc lamp was used as the source of radiation, which was focused through
the flame and onto a monochromator equipped with an intensified silicon
diode array detector. The system was used to measure absorption by hydroxyl
(OH) radical around 306 nm in the plume of a hybrid rocket motor. Hydroxyl
terminated polybutadiene (HTPB) was used as the fuel and gaseous oxygen
as the oxidizer. The experimental spectra were analyzed by comparison
with known vibrational and rotational lines using a multi-parameter curve-fitting
program. OH radical concentration and temperature profiles of the rocket
plume are presented along with details of the spectrometer specifications.
- Keywords: absorption spectroscopy,
hybrid rocket motor, combustion diagnostics
- Reprint
Information: Number of pages = 5.
Communications:
- Grass Tree Gum—(Australian Dragon’s Blood) by Dr. McCrea / John Kruse
- Review by L. Weinman of Explosives by R. Meyer, J. Köhler, and A. Homburg
- Review by Linda Pierpont of Propellants and Explosives: Thermochemical Aspects of Combustion by Naminosuke Kubota
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