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Trinitrotoluene (TNT) is an explosive of historical importance with a wide variability of reported performance due to the number of ways to prepare it. In this work, we focus on making a consistent data set for an Arrhenius Wescott-Stewart-Davis (AWSD) burn model for pressed TNT at 1.630 g/cm3. We look at a variety of data for the calibration of the reactant and product equations of state (EOS) and produce a Davis form for each EOS. We perform the rate law calibrations based on recent gas gun experiments and historical diameter effect data. We begin to explore several different choices made in the modeling. [ABSTRACT FROM AUTHOR]

Nitroaromatic compounds (NAC's) are extremely dangerous explosives having many detrimental effects on environment. Moreover, due to their wide range of production, they have gained worldwide attraction for social security and environment related issues due to their several applications in military and in engineering. Among these different nitroaromatic compounds, 2,4,6-trinitrophenol (picric acid, PA) and 2,4,6-trinitrotoluene (TNT) have received considerable attention in global security as well as environmental protection. In present report, we have developed a urea-derivatized extended triphenylene derivative by using palladium catalyzed Suzuki-Miyaura cross coupling which acts as fluorogenic chemosensor for the detection of PA and TNT. Further, chemosensor showed chromogenic behavior in the presence of trinitrotoluene where the solution changes its color from colorless to pink. Further, the practical applicability of chemosensor as sensory material has been demonstrated by utilizing the solution coated thin layer chromatography (TLC) strips for the contact mode detection of PA and TNT. [ABSTRACT FROM AUTHOR]

An amphibious, 6×6 wheeled, Light Armored Reconnaissance Carrier (LOTR) was tested in order to verify the effectiveness of the developed ballistic panel system. The equivalent of a 4kg TNT load was placed 440 mm from the vehicle floor under the center of mass; this represents a situation in which an IED is located under the ground. The obtained results show that numerical methods are very effective in explosion modelling. In the described case, a numerical model allowed a new ballistic panel system to be designed that provides better protection against pressure impulse. Different methods of connecting the layers of the panel were analyzed. Minor differences were observed when the acceleration of the vehicle and floor deflection were compared. [ABSTRACT FROM AUTHOR]

A complete model of Composition B-3 (Comp B-3; 60/40 wt% RDX/TNT) response to abnormal thermal conditions may include effects such as plastic yield stress, non-Newtonian viscosity, thixotropy, particle settling and dissolution, and thermal decomposition. In this work yield stress is modeled as a function of RDX particle volume fraction, which is a function of temperature at dissolution equilibrium. This Comp B-3 yield stress model was determined experimentally using an initially quiescent, non-isothermal falling sphere viscometer. The notion of critical particle volume fraction is employed and defined as a point below which yield stress is zero. Yield stress is derived from percolation theory and takes the form τy = B(ϕ - ϕc)N, where ϕc is critical particle volume fraction, and B and N are fitted constants. Results show that ϕc ~ 0.336, at an equilibrium mixture temperature of 158 °C. Yield stress for the quiescently melted material at the RDX/TNT eutectic temperature (78.3 °C) is calculated to be 146 Pa. [ABSTRACT FROM AUTHOR]

Detonation performance analyses were conducted for a number of evolving and potential high explosive materials. The calculations were completed for theoretical maximum densities of the explosives using the Jaguar thermo-chemical equation of state computer programs for performance evaluations and JWL/JWLB equations of state parameterizations. A number of recently synthesized materials were investigated for performance characterizations and comparisons to existing explosives, including TNT, RDX, HMX, and Cl-20. The analytic cylinder model was utilized to establish cylinder and Gurney velocities as functions of the radial expansions of the cylinder for each explosive. The densities and heats of formulation utilized in the calculations are primarily experimental values from Picatinny Arsenal and other sources. Several of the new materials considered were predicted to have enhanced detonation characteristics compared to conventional explosives. In order to confirm the accuracy of the Jaguar and analytic cylinder model results, available experimental detonation and Gurney velocities for representative energetic molecules and their formulations were compared with the corresponding calculated values. Close agreement was obtained with most of the data. [ABSTRACT FROM AUTHOR]

test of TNT is carried out, obtaining the radial propagation trajectories of shock waves and the evolution law of interfaces between detonation products (DP) and water by high speed rotating camera. The parameters of Jones-Wikins-Lee (JWL) equation of state (EOS) are calculated by thermodynamic program, and underwater explosion is simulated by dynamics software. The comparison between the results of calculation and experiment shows that, the track of water shock wave in radial can well describe the detonation product state of explosive, and the trace of interfaces between detonation products and water in radial can reflect the thermodynamic state of DP. [ABSTRACT FROM AUTHOR]

To better understand how solid carbon forms and evolves during detonation, we have prepared Composition B-3 (Comp B) with 13C and 15N-labeled 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and 2,4,6-trinitrotoluene (TNT) in order to trace the formation of soot from the carbon and nitrogen atoms in these explosives. Isotope-labeling of explosives has been performed in the recent past for a variety of reasons, including environmental remediation and reaction mechanism studies. Because it is expensive and time consuming to prepare these materials, and our detection equipment only requires trace amounts of isotopes, we have prepared fully-labeled materials and substituted them into unlabeled RDX and TNT at less than the 1% level. We will discuss the preparation and full characterization of this labeled Comp B, the detonation tests performed, along with the results of the post-detonation soot analysis. Various detonation models predict differing amounts and forms of carbon and nitrogen; these isotopically-labeled precursors have allowed these models to be tested. [ABSTRACT FROM AUTHOR]

Analyses were conducted on the behavior of explosives in a quasistatic detonation cycle. This type of cycle has been proposed for the determination of the maximum work that can be performed by the explosive. The Jaguar thermochemical equilibrium program enabled the direct analyses of explosive performance at the various steps in the detonation cycle. In all cases the explosive is initially detonated to a point on the Hugoniot curve for the reaction products. The maximum useful work that can be obtained from the explosive is equal to the P-V work on the isentrope for expansion after detonation to atmospheric pressure, minus one-half the square of the particle velocity at the detonation point. This quantity is calculated form the internal energy of the explosive at the initial and final atmospheric temperatures. Cycle efficiencies (net work/heat added) are also calculated with these procedures. For several explosives including TNT, RDX, and aluminized compositions, maximum work effects were established through the Jaguar calculations for Hugoniot points corresponding to C-J, overdriven, underdriven and constant volume detonations. Detonation to the C-J point is found to result in the maximum net work in all cases. [ABSTRACT FROM AUTHOR]

The thermal response of energetic materials is studied due to its importance in issues of material safety and surety. Secondary high explosives which melt before they thermally decompose present challenging systems to model due to the addition of material flow. Composition B is a particularly challenging system due to its multiphase nature with a low melt component (TNT) and a high melt component (RDX). The dissolution of RDX crystals in molten TNT at the temperature below RDX melting point has been investigated using hot stage microscopy. In this paper, we present data on the dissolution rate of RDX crystals in molten TNT as a function of temperature above the TNT melt. [ABSTRACT FROM AUTHOR]

Modified gap experiment (test) hydrocode simulations predict the trends seen in experimental excess free surface velocity versus input pressure curves for explosives with both large and modest failure diameters. Simulations were conducted for explosive "A", an explosive with a large failure diameter, and for cast TNT, which has a modest failure diameter. Using the best available reactive rate models, the simulations predicted sustained ignition thresholds similar to experiment. This is a threshold where detonation is likely given a long enough run distance. For input pressures greater than the sustained ignition threshold pressure, the simulations predicted too little velocity for explosive "A" and too much velocity for TNT. It was found that a better comparison of experiment and simulation requires additional experimental data for both explosives. It was observed that the choice of reactive rate model for cast TNT can lead to large differences in the predicted modified gap experiment result. The cause of the difference is that the same data was not used to parameterize both models; one set of data was more shock reactive than the other. [ABSTRACT FROM AUTHOR]

2,4,6-trinitrotoluene (TNT) is widely used in conventional and insensitive munitions as a fusible binder, commonly melt-cast with other explosives such as 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) or 3-nitro-1,2,4-triazolone (NTO). In this paper, we study the shock-to-detonation transition phenomenon in two melt-cast high explosives (HE). We have performed plate impact tests on wedge samples to measure run-distance and time-to-detonation in order to establish the Pop-plot relation for several melt-cast HE. Highlighting the existence of the single curve buildup, we propose a two phase model based on a Zeldovich, Von-Neumann, Döring (ZND) approach where the deflagration fronts grow from the explosive grain boundaries. Knowing the grain size distribution, we calculate the deflagration velocities of the explosive charges as a function of shock pressure and explore the possible grain fragmentation. [ABSTRACT FROM AUTHOR]

Cyclotol is a melt-castable high explosive composed of RDX and TNT, and typically a small amount of HMX. The term Cyclotol may apply to other mixtures of these components, but for the present work, experiments were conducted using Cyclotol containing 80 wt% RDX and HMX and 20 wt% TNT (we will refer to mixtures of RDX and TNT using the notation RDX%/TNT%). In the current effort, we report detonation velocity measurements at several diameters for unconfined rate sticks. The results are compared to prior diameter-effect data for Cyclotol 77/23, and a density-corrected Eyring-form fit for all available rate-stick data is reported. [ABSTRACT FROM AUTHOR]

FEFO is a liquid explosive with a density of 1.60 g/cm³ and an energy output similar to that of trinitrotoluene (TNT), making it one of the more energetic liquid explosives. Here we describe shock initiation experiments that were conducted using a two-stage gas gun using magnetic gauges to measure the wave profiles during a shock-to-detonation transition. Unreacted Hugoniot data, time-to detonation (overtake) measurements, and reactive wave profiles were obtained from each experiment. FEFO was found to initiate by the homogeneous initiation model, similar to all other liquid explosives we have studied (nitromethane, isopropyl nitrate, hydrogen peroxide). The new unreacted Hugoniot points agree well with other published data. A universal liquid Hugoniot estimation slightly under predicts the measured Hugoniot data. FEFO is very insensitive, with about the same shock sensitivity as the triamino-trinitro-benzene (TATB)-based explosive PBX9502 and cast TNT. [ABSTRACT FROM AUTHOR]

Electron attachment to gas phase nitrobenzene, all three isomers of mononitrotoluene and 2,4,6-trinitrotoluene is studied by means of two crossed electron-molecular beam experiments. We point out the formation of long-lived metastable parent anions and the most abundant anions produced via dissociative electron attachment (DEA). The experimental results are supported by quantum-chemical calculations, to determine the electronic configuration of selected molecular orbitals or the electrostatic potential mapped on an isosurface of the total electron density to find preferential sites of electron attachment. [ABSTRACT FROM AUTHOR]

TNT and TNT-aluminum composites were experimentally studied in an air-filled 26 m3 chamber for charge masses ranging from 1.1 to 4 kg. Large aluminum mass fractions (35 to 50%wt.) and particle sizes (36 μm) were combined with TNT in two configurations, whereby the aluminum particles were uniformly mixed in cast TNT or arranged into a shell surrounding a cast TNT cylinder. The results show that improved performance is achieved for the shell configuration versus the mixed version during the early afterburning phase (10–40 ms), while both approach the same quasi-static explosion overpressure (QSP) after a long duration. The QSP ratios with respect to TNT in nitrogen are in good agreement with equilibrium predictions. Thus, the large aluminum mass fraction improves spatial mixing of hot fuels with oxidizing gases in the detonation products and chamber air, resulting in more efficient afterburning energy release. [ABSTRACT FROM AUTHOR]

A trinitrotoluene (TNT) fracture surface image is characterized in terms of a self-affine fractal structure. The fracture surface was produced by high acceleration in an ultracentrifuge when the TNT strength was exceeded. An atomic force microscope (AFM) captured the topography of a 4 micron square region on the fracture surface. The present analysis supports a self-affine fractal description of the TNT fracture surface (wavelengths of 0.016 micron to 4.0 micron) and provides a new perspective on fracture processes in TNT. An essential step in self-affine fractal characterization of surfaces is the determination of reference surfaces. A self-affine fracture surface can be described in terms of a single-valued height function. In the TNT fracture surface, single-valued height functions, which describe surface texture, can only be defined with respect to curved reference surfaces. By employing curved reference surfaces, we have demonstrated that self-affine fractal scaling can be used to characterize the TNT fracture surface. This provides important information that is not evident in the analysis of individual surface scans. [ABSTRACT FROM AUTHOR]

This paper deals with the detection of nitroaromatic explosives. A specific fluorescent material is devoted to the detection of ultra traces of explosives remaining on clothes. The sensor exhibits a large sensitivity for TNT or DNT vapors. [ABSTRACT FROM AUTHOR]

The article cites a study that evaluates the use of deep ultraviolet resonance Raman spectroscopy technique in the detection of explosives. This techniques was tested against several explosives such as trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN) and cyclotrimethylene-trinitramine (RDX). According to researchers, the luminescence from fluorophores can totally obscure the Raman signal from the explosives, thereby precluding detection and identification of explosives.

This paper deals with the use of SAW gas sensors for the detection of explosives vapors. The developped sensor exhibits a large sensitivity towards DNT, TNT and EGDN. [ABSTRACT FROM AUTHOR]