REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

Shockwave Overpressure of Propellant Gases
Around the Mortar

MIODRAG LISOV

Military Technical Institution, Ministry of Defence, Serbia

SLOBODAN JARAMAZ

University of Belgrade, Faculty of Mechanical Engineering, Serbia, sjaramaz@mas.bg.ac.rs

MIRKO KOZIć

Military Technical Institution, Ministry of Defence, Serbia, mkozic@open.telekom.rs

NOVICA RISTOVIć

Military Technical Institution, Ministry of Defence, Serbia

Abstract: This paper resulted from many years of research of the overpressure of the shockwave of the powder gases, which occurs during firing from the mortar. The cause for these occurences is a sudden flow of powder gases from the weapon barrel and its expanding in the undisturbed environment. In this paper is shown influence of propellant charge on overpressure intensity of shockwave produced by powder gases nearby mortar. The research comprised modelling and computation of the overpressure field, around the weapon, because of determining its intensity and distribution in space and time. With the aim of the real description of the mentioned occurences the theoretical part was given, and then the numerical modelling of the instantaneous flow of the powder gases from the motrar barrel has been coducted. Experimental results are achieved by the firing experiments from the 120mm mortar. Computation and experimental results are given in the form of a chart of the barrel pressure change and overpressure of powder gases, at the characteristic measuring points around mortar..

Keywords: gas dynamics, propellant charge, overpressure, powder gases, interior ballistics, mortar.