摘要:

AbstractWhen several liners as well as high explosive charges are produced in identical and reproducible ways resulting in identical or at least similar sizes and geometries, differences in the total lengths of the shaped charge jets will indicate differences in copper quality.This paper outlines guidance for taking flash X‐ray pictures of shaped charge jets for this purpose, and for an analysis of the pictures at least for a comparative assessment. The penetrating capability can be derived from the particulation time

ISSN:0721-3115    

DOI:10.1002/prep.19850100502

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThe ammonium perchlorate (AP)‐oxidized composite propellants, each of which contains separately copper chromite (CC) as a burning rate adjuster and carbon black (CB) as an opacifier, have been ignited at subatmospheric pressures of argon gas by means of a carbon dioxide laser, and the effects of the additives on the ignition behavior have been studied. It has been found that copper chromite shortens the ignition time especially below 100 torr and that at the same time it enhances the ignitability, i.e., self‐sustaining ignition.Carbon black, being an opacifier decreasing reflectivity and increasing radiative absorption at propellant surface, can not be recognized to be an active catalyst in ignition at subatmospheric pressures.The data of differential thermal analysis (DTA) for above specimens have indicated that the maximum exothermic peak temperature is shifted toward a lower one with the increase in CC concentration, the exothermic peak structure becoming sharper. However, CB addition to the basic propellant makes exothermic peaks less distinct. The results of DTA support those obtained from the ignition experiments ab

ISSN:0721-3115    

DOI:10.1002/prep.19850100503

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractIn spite of many publications dealing with the thermal decomposition of the cyclic nitramines RDX and HMX, the decomposition behavior of nitroguanidine (nigu), especially in the low temperature range, has not been investigated fundamentally in the past. Because nitroguanidine is an important explosive component for triple base propellants, a better understanding of the thermal decomposition at low temperatures is of interest.For example, aging studies of triple base propellants exhibited a different decomposition behavior from single and double base propellants. Therefore nigu is supposed to influence the safe life time of propellants containing nitric acid esters.The investigations of the decomposition of nigu published in the past, have been performed at temperatures between 190°C and 240°C. The aim of this work was to study the decomposition behavior of nigu at temperatures as low as possible.In this connection, temperatures between 110°C and 240°C have been used. In this temperature range, nitroguanidines with different grain sizes have been investigated by measuring the weight loss and analyzing the decomposition gases by mass spectrometry. Also solid residues, like ammeline and melamine, remaining after the degradation tests were analyzed quantitatively by using high performance liquid chromatography. The formation of melamine and ammeline was found to depend strongly on the amount of the weight loss of nigu. The better stability behavior of triple base propellants is possibly due to the formation of NH3which is being formed in the decomposition process of nigu. Ammonia reacts with nitric oxides and behaves therefore similar as a stabili

ISSN:0721-3115    

DOI:10.1002/prep.19850100504

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractTriple aminoalkylation of nitromethane with formaldehyde and tert‐butylamine resulted in a cyclic Mannich base, the nitrolysis of which gave 1,3,5‐trinitro‐hexahydropyrimidine. Hydroxymethylation and subsequent nitration converted it to 5‐nitroxymethyl‐1,3,5‐trinitro‐hexahydropyrimidine. Both compounds exhibit pronounced explosi

ISSN:0721-3115    

DOI:10.1002/prep.19850100505

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractTo obtain a further insight into the complex flame acceleration process of deflagrating fuel/air mixtures experimental investigations were carried out in free and partially confined homogeneous clouds with hydrogen as a fuel. The results of the experiments in an unconfined hemispherical configuration show a distinct dependence of the flame velocity on the cloud size which does not exceed, however, an upper limiting value. The experiments under partially confined conditions without additional turbulence indicate that the flame velocity and consequently the pressure field is governed by the hemispherical flame front initially formed; i.e. the flame velocity is not affected by the partial confinement. To increase the turbulence effects further experiments were carried out with a fan and with jet ignition. In the case of fan induced turbulence the flame velocity was strongly influenced by the fan speed. At a certain fan capacity the transition of a deflagration into a detonation was observed. With jet ignition produced by venting an explosion chamber into the partially confined cloud the transition occured even with hydrogen concentrations in air as low as 22 vol%. The results which are discussed on the basis of turbulence models show that high damaging overpressures or the transition from a deflagration into a detonation are only generated by strong turbulences as a consequence of flow and/or obstacles.

ISSN:0721-3115    

DOI:10.1002/prep.19850100506

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThis note first establishes a correlation between post impact fuze delay and the spread of explosives of a squash head gun‐fired projectile when hitting a rigid non‐yielding plate. Estimations of optimum strike velocity and fuze delay to maximize spread are deri

ISSN:0721-3115    

DOI:10.1002/prep.19850100507

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

ISSN:0721-3115    

DOI:10.1002/prep.19850100508

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

ISSN:0721-3115    

DOI:10.1002/prep.19850100501

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY