A Labscale Hybrid
Rocket Motor for Instrumentation Studies
R. Shanks and M. K. Hudson
[Dept. Applied Sci. & Grad. Inst. Tech., U Ark LR, Little Rock,
AR 72204 USA]
Abstract: An interest in plume
spectroscopy led to the development of a labscale Hybrid Rocket
Facility at the University of Arkansas at Little Rock (UALR). The
goal of this project was to develop a reliable, consistent rocket
motor testbed for the development of plume spectroscopy instrumentation.
Hybrid motor technology was selected because it has proven to be
safe and inexpensive to operate. The project included the design
and construction of the labscale hybrid rocket motor, the supporting
facility, the instrumentation and computer control of the motor,
and the characterization of this particular thruster, including
the regression rate of hydroxyl-terminated polybutadiene (HTPB)
fuel grains. For plume spectroscopy experiments, the fuel is doped
with metal salts, to simulate either solid motors or liquid engines.
It was determined the labscale hybrid motor produces a reliable
and consistent plume, resulting in an excellent tool for the development
of plume spectroscopy and other instrumentation.
PyroTech AB, Box 93, S-427 23, Billdal, Sweden]
Abstract: A chemical analysis of
a selection of fireworks has been made. The products were chosen to
represent the typical use of consumer fireworks in Sweden 1998. The
purpose of the assignment was to estimate to what extent consumer fireworks
contribute to the total emission of some undesirable elements in Sweden.
Six consumer items were examined (two of them being multi item kits).
Nineteen elements were analyzed, but focus was made on the environmentally
undesirable elements arsenic, cadmium, lead and mercury.
The conclusion was that, as far as arsenic, cadmium and mercury are
concerned; the contribution from consumer fireworks is insignificant
compared with the total emission and deposition within the country.
The emission of lead, which is a well-known constituent in crackling
fireworks effects, can at most be 0.8 % of the total emission and deposition
in the country.
The figures in this paper do not provide any evidence in favor
of restricting the lead content of fireworks.
Abstract: Propellants used for
pyrotechnics are composed of energetic materials that produce high-temperature
and high-pressure gaseous products. The propellants are classified
into three types by their physical structure and the ingredients
used: (1) homogeneous propellant consisting of chemically bonded
oxidizer and fuel components in the same molecule, (2) heterogeneous
propellant consisting of physically mixed oxidizer and fuel components,
and (3) granulated propellants consisting of energetic solid particles.
While the energy content of propellant is determined by the chemical
properties of the ingredients, the physical properties and chemical
processes of the ingredients determine the ballistic characteristics
such as burn rate and pressure and temperature sensitivities.
Keywords: propellant chemistry
of the Thermal Stability and Sensitiveness of Sulfur/Chlorate Mixtures
Part 3. The Effects of Stoichiometry, Particle Size and Added Materials
D. Chapman, R. K. Wharton, J. E. Fletcher[Health & Safety Lab., Harpur Hill, Buxton,
Derbyshire, SK17 9JN, UK]and A. E.
Webb[HM Explosives Inspect., Health
& Safety Exec., St Anne’s House, Trinity Rd, Bootle, Merseyside,
L20 3QZ, UK]
Abstract: The effects of stoichiometry
and particle size on the thermal stability and sensitiveness of
sulfur/chlorate mixtures have been investigated. Mixtures containing
small particles and approximately 5% sulfur were shown to be the
least thermally stable. Sulfur/chlorate mixtures containing a third
component have also been investigated and compositions with up to
70% added material gave similar low ignition temperatures to mixtures
of the two components. All compositions containing sulfur/chlorate
were found to be friction sensitive and had limiting loads below
the 80 N UN transport criterion. When iron was the third component,
the compositions were also impact sensitive, with Limiting Impact
Energies below the 2 J UN transport criterion.
Keywords: chlorate, sulfur,
sensitiveness, thermal stability, ignition temperature
Morphologies — Metal Fuels
K. L. & B. J. Kosanke[PyroLabs,
Inc., Whitewater, CO 81527, USA]and
Richard C. Dujay[Mesa State College,
Electron Microscopy Facility, Grand Junction, CO 81501, USA]
Abstract: The morphology (size,
shape and surface features) of the constituent particles in a pyrotechnic
composition affects its performance. This is particularly true of
metal fuel particles in the composition. Particle morphology can
also constitute an important part of forensically establishing a
match between materials of known origin and evidence. This article
catalogs and briefly discusses some characteristic features commonly
associated with metal fuels in pyrotechnic compositions.
Keywords: morphology, metal
fuels, forensics, pyrotechnics
“Matches”, An Over-Inference of Data? A Giglio Obligation?
Abstract: The expert witness
who over-infers his data through the misuse of adjectives of comparison
opens himself up to cross-examination that can and will discredit
his work product. This paper uses the example of forensic analysis
of black powder explosive to demonstrate that one can not categorically
“match” one Black Powder sample to another or very often one complex
chemical system to another and that even if this were possible,
such “matches” may have limited probative value. The paper also
explores the legal obligation of the expert to reveal to the prosecutor,
court and trier-of-fact the limitations of the probative value of
the evidence where those limitations might be considered to be exculpatory
Keywords: Black Powder, forensic
analysis, Giglio, sulfur, potassium nitrate, charcoal
Study on Various
Polyesters as Binders for Pyrotechnic Composition
J.P. Agrawal, S.N. Singh, D.B. Sarwade,
V.A. Mujumdar & NT Agawane
[High Energy Materials Research Laboratory, Sutarwadi, Pune 411 021,
Abstract: Two tracer compositions
were formulated based on magnesium, strontium nitrate and sodium
nitrate with unsaturated non-halo and halo polyesters as binders.
They were characterized for mechanical properties, thermal behaviour,
burning rate, luminous output, and impact, friction and spark sensitivities.
The data show that the composition with chloropolyester as binder
is better for tracer compositions.
The Effect of Sample Containers on the Ignition Temperature of Sulfur/Chlorate
Mixtures by D.
Please send comments and suggested corrections to: B. Kosanke,
Publisher, Journal of Pyrotechnics, Inc.
1775 Blair Road Whitewater, CO 81527 USA
You Can Help Keep Fireworks Legal
Did you know that efforts are underway in the United States at both State
and Federal levels to ban consumer fireworks and rocketry forever? You
can help turn the tide by joining the Fireworks Alliance.
It's free, and we need your voice today!