B. Veyssiere's research while affiliated with French National Centre for Scientific Research and other places

Publications (60)

Article
The main features of nano-sized thermites are reviewed with the purpose to compare the performance of most reactive nanothermites showing high combustion front velocities of up to 2500 m s−1 with that of primary explosives. Because these regimes do propagate only at very low relative density of nano-thermites and as convective burning waves rather...
Article
The mechanism of superior efficiency of lead azide (LA) in comparison with mercury fulminate (MF) is not understood. Indeed, both primary explosives have quite close detonation velocities and result in a large amount of condensed lead (Pb) and mercury (Hg), respectively. We explore an idea that the high efficiency of LA is due to the fact that the...
Article
Experimental and numerical study of the detonation has been conducted in heterogeneous reactive two-phase media made of liquid isooctane sprays dispersed in gaseous oxidizing atmospheres. Influence of the oxidizer composition on conditions of detonation formation and propagation regimes, with particular attention on the existence of the so-called c...
Article
Full-text available
Experimental data on the interaction of detonation and shock waves with permeable barriers in cylindrical channels in hydrogen—air mixtures are presented. The method of soot tracks on semi-cylindrical smoked inserts made it possible to elucidate the mechanisms of initiation of the detonation downstream of the barriers. The possibility of initiating...
Article
We present results of an experimental study of blast wave propagation and particle dispersion induced by a free-field detonation of spherical charges made of a 125 g C-4 explosive surrounded by inert or reactive particles. Visualization of the flow was performed with a high-frame-rate video camera. Background oriented Schlieren (BOS) methods were a...
Article
The paper explains the mechanism of tulip flame formation in horizontal combustion chambers closed at the ignition end. The explanations are based essentially on the PIV images and the direct visualization of the process. The obtained results demonstrate that the tulip flame is a purely hydrodynamic phenomenon which results from the competition bet...
Article
The present paper deals with a problem of explosion initiated in a vessel and vented through a duct. On the basis of numerical simulation (CFD) and visualization by means of high speed camera it completes and discusses the existing results and hypotheses (especially those presented in the work of Ponizy and Leyer [1]) concerning the process of enha...
Conference Paper
Full-text available
Present work has permitted to define the characteristics of an experimental configuration relevant to study the direct initiation of aluminium-oxygen suspensions, based on an estimation of the critical initiation energy of 1kg TNT and the critical detonation radius of the order of magnitude of 1m. The experimental plant has been built. First experi...
Conference Paper
An experimental setup has been designed which permits to study the initiation and propagation of a detonation in liquid fuel sprays in controlled (granulometry and concentration of the spray) and reproducible conditions. It was shown that it is possible to initiate a detonation in liquid fuel in air under standard initial conditions of temperature...
Article
Recently we have used scarce available data on the detonation cell size in suspensions of aluminium particles in air and oxygen to adjust the kinetic parameters of our two-phase model of detonations in these mixtures. The calculated detonation cell width was derived by means of two-dimensional unsteady simulations using an assumption of cylindrica...
Article
Full-text available
The direct use of dry biomass dust as a fuel in reciprocating engines could be of great interest because of the large availability of plant matter and the versatility of Internal Combustion Engines (ICE). Coal dust was used in the past and mostly in slurries because of large production during industrial era in Europe but led to many problems caused...
Article
Full-text available
An experimental investigation was performed to establish the dependence of concentration limits of detonation re-initiation behind a multi-orifice plate on mixture composition and initial pressure for hydrogen–air mixtures. The experiments were carried out in detonation tubes of diameter 106 and 141 mm, separated by a multi-orifice plate into two s...
Article
Full-text available
An experimental study is presented of the influence of detonation wave parameters and detonation product composition upstream of a perforated plate on the onset of detonation downstream. Experiments were performed in detonation tube 106 mm in diameter, separated into two sections by a perforated plate combined with a diaphragm. The tube was equippe...
Article
Heterogeneous detonations involving aluminium suspensions have been studied for many years for industrial safety policies, and for military and propulsion applications. Owing to their weak detonability and to the lack of available experimental results on the detonation cellular structure, numerical simulations provide a convenient way to improve th...
Article
An experimental method has been developed to investigate the mechanisms of dust suspension generation in a closed vessel under microgravity conditions. The objective is to characterize the evolution as function of time of the aerodynamic flow field and the dust distribution inside the vessel, in particle concentration conditions representative of a...
Article
Shock wave dispersion and ignition of solid combustible particles is a fundamental problem of great importance for various applications. For example, metallized explosives are designed and produced to generate specific effects different from those obtained with homogeneous ones, such as delayed energy release; but their exact working mechanism rema...
Article
Full-text available
We present results of an experimental study of blast wave propagation and particle dispersion induced by a free-field detonation of spherical charges made of a 125 g C-4 explosive surrounded by inert or reactive particles. Visu-alization of the flow was performed with a high-frame-rate video camera. Background oriented Schlieren (BOS) methods were...
Book
Extensively using experimental and numerical illustrations, Combustion Phenomena: Selected Mechanisms of Flame Formation, Propagation, and Extinction provides a comprehensive survey of the fundamental processes of flame formation, propagation, and extinction. Taking you through the stages of combustion, leading experts visually display, mathematica...
Chapter
Combustion has a very long history. From antiquity up to the middle ages, fi re along with earth, water, and air was considered to be one of the four basic elements in the universe. However, with the work of Antoine Lavoisier, one of the initiators of the Chemical Revolution and discoverer of the Law of Conservation of Mass (1785), its importance w...
Article
Detonation initiation is investigated in aluminium/oxygen and aluminium/air mixtures. Critical conditions for initiation of spherical detonations are examined in analogy with the criteria defined for gaseous mixtures, which correlate critical parameters of detonation initiation to the characteristic size of the cellular structure. However, experime...
Article
Full-text available
The cellular detonation structure has been recorded for hybrid hydrogen/air/aluminium and hydrogen/oxygen-argon/aluminium mixtures. Addition of aluminium particles to the gaseous mixture changes its detonation velocity. It appears that the correlation between the cell size and the detonation velocity of the hybrid mixture is similar to the correlat...
Article
Full-text available
Decomposition products of a solid propellant are considered as a possible fuel in an airbreathing pulse detonation engine (PDE). However, these decomposition products contain not only gaseous species but also a significant amount of solid carbon particles. Whether performance can be improved by burning these particles is investigated numerically. T...
Article
Combustion mechanisms of a suspension of solid particles in a gaseous mixture are studied with the aim of correlating the constant volume explosion characteristics with the initial state of the suspension at ignition time. Two vessels have been specially designed, one transparent with an octagonal cross section, allowing visualization and, the othe...
Article
The uses of detonation in gas-solid particle mixtures for aerospace vehicle propulsion due to its high energetic potential, are discussed. The detonations involving fine solid particles suspended in a gaseous phase are classified based on the chemical nature of the different components. The characteristic chemical reaction time for heterogeneous re...
Article
A solution allowing quiet evacuation of gases in a vented explosion propagating from a vessel into a discharge duct has been studied. It consists in placing a wire-net insert at the duct entrance in order to delay flame penetration into the duct and prevent the occurrence of a secondary explosion. Experimental results demonstrate that the secondary...
Article
The cellular detonation structure has been recorded for hybrid hydrogen/air/aluminium mixtures on 1.0 m 0.110 m soot plates. Addition of aluminium particles to the gaseous mixture changes its detonation velocity. For very fine particles and flakes, the detonation velocity is augmented and, in the same time, the cell width diminishes as compared wit...
Article
Effect of addition of magnesium particles on the detonation characteristics of methane-oxygen-nitrogen mixtures at elevated initial pressures is predicted by numerical calculations. Two rich (r=3, ZN2/ZO2=5 and r=2.8, ZN2/ZO2=2.9) mixtures under 40 bar initial pressure are considered. It is shown that an increase of the detonation velocity of the r...
Article
Full-text available
The experiments were carried out in a cylindrical closed vessel of 8.5-L capacity, made of transparent organic glass. Propane-air mixture was used; pressure history was measured. A high-speed video camera recorded the history of flame propagation. During the experiments the vessel was located inside the cage of a drop-tower assembly. The microgravi...
Article
To explain the experimental results obtained in the 30 mm Ram accelerator at ISL, showing that in the subdetonative mode, the terminal velocity of magnesium projectiles at the end of Ramac tube is higher than the CJ detonation of the propellant gaseous mixture, whereas the projectile undergoes a mass loss during the propagation, the assumption is m...
Article
The paper deals with the problem of mitigation of the explosion initiated in a vessel and vented through a duct. A solution has been studied which allows quiet evacuation of the explosion gases, without combustion intensification in the vessel and enhancement of explosion overpressures, characteristic in such a system. This can be obtained by retar...
Article
The effect of radial acceleration in a rotating vessel on flame propagation has been investigated experimentally. Methane–air mixture compositions between the lean flammability limit and stoichiometric were studied. The behavior of flame propagation and the extinction mechanism were examined in detail. The flame propagating in a rotating vessel is...
Article
The existence of a secondary discontinuity at the rear of a detonation front shown in experiments by Peraldi and Veyssiere (1986) in stoichiometric hydrogen-oxygen mixtures with suspended 20-m starch particles has not been explained satisfactorily. Recently Veyssiere et al. (1997) analyzed these results using a one-dimensional (1-D) numerical model...
Article
There are important discrepancies in the results of detonation studies of starch particle suspensions in various gaseous atmospheres. The problem of heterogeneous detonation of this kind is studied with the help of a numerical model based on the same main assumptions as have been used previously for modeling non-ideal detonations in suspensions of...
Article
The problem of detonation initiation is studied in the case of hybrid two-phase mixtures consisting of a hydrogen-air gaseous mixture with suspended fine aluminium particles. In preceding works on this subject, investigation of the steady propagation regimes has shown that three main propagation regimes could exist: the Pseudo-Gas Detonation (PGD),...
Article
The problem of propagation of steady nonideal detonations in heterogeneous hybrid mixtures is studied in the case of a hydrogen-air gaseous mixture with suspended fine aluminum particles. Due to the difference in the order of magnitude of the characteristic induction and combustion times of gaseous mixture and solid particles, the process of energy...
Article
If the ability of reactive solid particles to give rise to combustible mixtures when they are finely dispersed in an oxidizing gas is well known since a long time, the actual mechanisms governing the propagation of combustion in this kind of reactive mixtures is far from being well understood. The reason for this is an insufficient knowledge of the...
Article
To improve protection against the consequences of dust explosions, fundamental research must be carried out to obtain better understanding of the mechanisms of flame propagation in solid particle—gas mixtures. In the present paper are summarized some of the fundamental studies conducted at the Laboratoire d'Energétique et de Détonique (LED) of Poit...
Article
Full-text available
Calculated data are analyzed within the scope of statement of the problem of ignition of fine particles dispersed in an atmosphere by explosion of a central charge (TNT). Equations of state for the detonation products suggested by V. F. Kuropatenko, and for air by V. I. Okhitin and V. V. Koren'kov are used. Three types of particle dynamics are dete...
Article
Full-text available
The problem is stated of ignition of metal particles in damped shock waves for a unidimensional nonsteady-state gas flow (with different forms of symmetry) which arises from explosion of a central charge. Calculated data are discussed for this problem in the case of progressive movement of a gas with a powerful explosion. Three types of particle dy...
Article
Comparison of experiments in gaseous detonable mixtures containing aluminum particles in suspension with results of our previous approximate model has shown that under certain concentration of particles a steady double-front detonation (DFD) may propagate. The first front is supported by heat release from gaseous components, while the heterogeneous...
Article
The process of initiation and propagation in shock tube of stationary detonations in suspensions of the Al-particles of various size and shape has been investigated experimentally. The Al-suspensions of mean size which is more than 10 μm didn’t ignited neither in air medium nor in the oxygen one. Al-air-suspensions with scales-like particles of thi...
Book
In hybrid mixtures made of a combustible gaseous mixture with reactive solid particles in suspension, different propagation regimes of non-ideal detonation may be met: Double Front Detonations (DFD) Single Front Detonations (SFD). Their occurrence is linked to the nonmonotonous process of heat release. The problem is studied in the case of Hydrogen...
Article
Propagation of starch-dust air flames has been investigated in a tube (3 m long; square cross section 0.2 m × 0.2 m). Laminar, cellular and slightly turbulent propagation regimes have been observed. Several analogies with premixed gaseous flames have been displayed. Conduction heat transfer through the flame appears to be predominant for preheating...
Article
Preliminary works performed in order to determine the laminar burning velocity of spray flames by the tube method are reported. The experimental setup mainly consists in a 0.1m x 0.1 m square cross section, 1 m long, vertical tube. The transparent glass walls allow visualization of flame propagation. The spray is generated by means of an ultrasonic...

Citations

... The characteristic feature of nanothermites is a dramatically high burning velocity, close to the values already characteristic of the detonation process. However, it should be remembered that burning of nanothermites does not follow the detonation mechanism [202]. Usually tests are performed in closed vessels, such as tubes. ...
... Coordination compounds with azide ligand have been studied for decades, not only for their potential use as detonation agents or explosives [1][2][3][4][5], but also because of the intrinsic properties of N 3 − as a "pseudo halogen" [6,7] and as a subject of magnetism [8]. Many studies of stable azide coordination compounds have been reported, and the Cambridge Structural Database (2020 release) contains over 5000 items having at least one coordinated azide ligand [9]. ...
... The flow lines indicate the direction of mass flow. becomes rich and the local flame speed decreases [58]. At the convex part of the flame, the fuel-air mixture becomes leaner and the local flame speed increases due to the rapid diffusion of the fuel than the oxidizer [59]. ...
... It should be noted that multi-dimensional detonation waves with Arrhenius kinetics are unconditionally unstable (Short & Stewart 1998). Numerical truncation errors can induce the transverse instability after the wave propagates a few hundred half-reaction-lengths (Khasainov, Virot & Veyssière 2013;Benmahammed et al. 2016). Thus, in the inlet channel region, the planar detonation flow is calculated in a one-dimensional manner. ...
... For shock analyses, see, for example, Hoover and Hoover[34], Gregoire et al.[35], Kudryashova et al.[36], Cabalo et al.[37,38].3 One conclusion from these experiments was that aerosols generated from a blast containing toxic materials cannot be assumed to be inactivated by the blast itself, which is consistent with findings of Eshkol and Katz[39], and Kanemitsu[40], where Hepatitis B from a suicide bomber was transmitted to survivors of the blast. ...
... Up-to-date reviews of state-of-the-art particle combustion science and technology of this type therefore regularly appear in textbooks 65) . Combustion science also relates to achieving advanced (military) goals such as powering hypersonic aircraft using detonation-based engines, possibly fueled by aluminum nanoparticles 66) . ...
... In one of these, a thin diaphragm separates the gases upstream and downstream of the perforated plate [2,3]. In the other, the diaphragm is absent and the mixture composition on both sides of the plate are similar [2,5]. In either case, the mixture upstream of the perforated plate is detonated. ...
... In particular a better knowledge of the different flame propagation regimes i s necessar^'. In this area, some progresses have been performed in the recent years (Proust and Veyssiere, 1988; Rzal et al., 1991; -Kauffman et al., 1987; Wolanski et al., 1990; Mazukiewicz et al., 1990; Pu et al., 1988 ...
... Besides, it was indicated that the size of the individual orifice of the perforated plate should not exceed the detonation cell width to ensure a reliable quenching of the transverse wave structure. Medvedev et al. (2005) and Khomik et al. (2013Khomik et al. ( , 2014 utilized the perforated plate to form a jet and investigated the impact of a stable detonation wave in hydrogen-air and hydrogen-oxygen-nitrogen mixtures. The former found critical conditions of OD. ...
... Thus, the detonation performance of the ternary cloud is dictated by both the concentration and the shape of the cloud formed at the end of the explosive dispersal of the mixture. Considerable effort has been devoted to investigating the explosive dispersal of liquids and dry/wetted particles [2,4,5,[12][13][14][15][16][17][18][19][20][21]. One of the defining characteristics of the explosive dispersal of liquids and particles is the widely observed jetting instability that occurs on the timescale of shock interaction [2,5,[12][13][14][15][16][17][18][19][20][21]. ...