Wyniki wyszukiwania - Biblioteka Nauki

1

Closed Vessel Investigation of Propellant Ignition Process with Using Capillary Plasma Generator

100%

Michalski J. , Leciejewski Z.

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2015

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tom Vol. 6, Nr 1 (19)

19-26

EN

Previous published results of closed vessel investigations indicated that classical primers (electric or percussion with black powder bedding) when used with LOVA propellants cause unstable burning, deflagration or even lack of ignition. CPG is one of the most reliable ignition sources which make possible a reduction of temperature gradient effect and control combustion process. Comparable tests of black powder and plasma ignition in closed vessel with conventional NC propellant were done. Shorter ignition time while using plasma was achieved.

2

An investigation of the preparation and performance of microcellular combustible material

88%

Yang W. , Li Y. , Ying S.

Central European Journal of Energetic Materials

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2014

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tom Vol. 11, no. 2

257--269

EN

Microcellular combustible materials, based on poly(methyl methacrylate) (PMMA) bonded RDX, were fabricated by the pressure quench method using supercritical CO2. After foaming, the bulk density, porosity, expansion ratio and cell density were analyzed. Scanning Electron Microscopy (SEM) has also been used to investigate the influence of the foaming conditions (temperature, saturation pressure and depressurization time) and the RDX ratio on the porous structure. The skin-core structure was also observed after the pressure quench process. The mechanical sensitivities and burning performance were investigated by the friction sensitivity test, the impact sensitivity test and the closed vessel test, respectively.

3

Comparative closed vessel tests : influence of ignition and loading conditions on propellant burning rate

75%

Leciejewski Z. K.

Materiały Wysokoenergetyczne

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2011

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tom T. 3

57--63

EN

The most widely used experimental method to determine and to compare energetic and ballistic properties (force, co-volume, coefficients of burning rate law) of different propellants is burning a specific amount of propellant in a closed chamber. The procedure of determining the values of the individual material constants recommends similar conditions of closed vessel investigations like limited range of loading density and determined mass of black powder (igniter material) for determined loading density. There also often occurs the need for performing of closed vessel comparative tests (carried out for two or more numbers of propellants), where one of them serves the role of a reference propellant and in relation to which described are the differences between the characteristics of the remaining propellants are described. Comparative tests of propellants should be understood to be such tests performed for identical loading conditions, including firstly the same closed chamber capacity, mass of the propellant burned (thereby the identical loading density) as well as identical ignition conditions which are understood as the same mass and the same type of igniter material. In the present paper the influence of ignition and combustion conditions during closed vessel tests on possible deviations in determination of burning rate is analysed as a function of incident heat flux.

4

Experimental Assessment of Primer Pressure in 9 mm Pistol Ammunition

75%

Fikus B. , Surma Z. , Trębiński R.

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tom Vol. 11, Nr 2 (40)

25--30

EN

n theoretical simulations of internal ballistics phenomena, the value of pressure generated by the ignition system is required. Typically, the ignition pressure value is assumed to be 3 - 5 MPa. The work presents a measurement stand using a “micro closed vessel”, designed to determine the ignition pressure for 9 mm pistol ammunition. Pressure measurements were made for two types of ammunition, differing in the construction of the ignition system. The results of measurements indicate that the value of the ignition pressure is twice as high as usually assumed. In addition, the mass of the ignition charge was determined, which is used in selected models of internal ballistics. The mass value was at the level of 0.02 g.

PL

W symulacjach zjawisk balistyki wewnętrznej układów miotających wymagana jest znajomość wartości ciśnienia wytwarzanego przez układ zapłonowy. Wartość ta jest istotna z punktu widzenia opisu procesu spalania materiału miotającego w początkowej fazie strzału, co wynika z znaczącego wpływu ciśnienia gazów prochowych na szybkość spalania materiału miotającego. Ten fakt z kolei przekłada się na maksymalną wartość ciśnienia w przestrzeni zapociskowej. Zazwyczaj przyjmowaną wartością ciśnienia zapłonu jest wartość na poziomie 3 – 5 MPa. Niestety w dostępnej literaturze uwidacznia się brak oszacowań wartości ciśnienia generowanego przez spłonkę amunicji strzeleckiej. Biorąc pod uwagę ten fakt, w pracy przedstawiono stanowisko pomiarowe, wykorzystujące mikrokomorę manometryczną, przeznaczone do pomiaru ciśnienia zapłonu dla 9 mm amunicji pistoletowej. Dokonano pomiarów ciśnienia dla dwóch rodzajów amunicji, różniących się budową układu zapłonowego. Otrzymane rezultaty wskazują, że wartość ciśnienia zapłonu jest dwukrotnie wyższa niż zazwyczaj przyjmowana. Ponadto określono masę ładunku inicjującego, która wykorzystywana jest w wybranych modelach balistyki wewnętrznej. Wartość masy kształtowała się na poziomie 0,02 g.