Scientific report. ARL-TR-
2473. Army Research Laboratory. Aberdeen Proving Ground, MD, 2001. – 41 p.Barrel heating and erosion concerns for the Navy are being brought to light by new extended-range munitions. These munitions have, in general, higher performance requirements and use new propellants. In light of these concerns, the following investigation was performed to determine the thermal and erosion characteristics of the current and proposed munitions. In this report, the calculation methodology governing both the thermal and erosion work is described. Six thermal scenarios were computed to compare the thermal load from various combinations of charges. Single-shot erosion predictions are presented for three charges: MK67 with NACO propellant, MK73 with M30A1 propellant, and EX167 extended-range guided munitions (ERGM) propelling charge with EX99 propellant. A fourth single-shot erosion calculation was made using the product gas-state variables and gas velocity of the MK73 charge with chemical constituents of EX99 propellant. The erosion results highlight propellant combustion product differences at the surface between the current and newer propellants. The primary conclusion is that carbunzation leading to iron carbide formation may be an important contributing factor for much of the material lost from the steel barrel once it is exposed through cracks or chips in the surface coating.Contents:
Introduction.
Mechanistic Descriptions.
Heat Transfer .
Erosion Methodology.
Surface Description.
Erosion Calculations.
Thermal Calculations.
Conclusions.
References.
Distribution List.
