Interior Ballistic Calculations Using an Accurate Equation of State for the Propellant Gases
Abstract
The use of an accurate equation of state for propellant gases in interior ballistic calculations is very important for two reasons. The burning rate of the propellant depends on the pressure and it is the pressure that performs work on the projectile. Also, as interior ballistic codes become more sophisticated, propellant gas transport properties will have to be taken into account. Both viscosity and thermal conductivity should be important. Since different propellant gases have different transport properties, the composition of the propellant gas will have to be known as a function of time. It was shown many years ago that the Abel-Nobel equation, which is used for interior ballistic calculations is not very accurate. Also the covolume for each individual propellant is required thus introducing an extra adjustable parameter. In this work the interior ballistic code IBHVG2 is modified so that for each step of the ballistic cycle the equilibrium gas composition and pressure are calculated. The energy loses calculated by IBHVG2 are subtracted from the heat of formation of the propellant consumed before the equilibrium calculation is performed. The accurate equation of state proposed by Powell, Wilmot, Haar, and Klein is used. The covolume for each individual propellant is no longer required and the propellant gas composition inside the gun is monitored as a function of time. Ballistic performance using this approach is compared to the more conventional IBHVG2 calculation.... Interior ballistics, Equation of state, MCVECE Thermochemical code.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1993
- Accession Number
- ADA263014
Entities
People
- A. K. Macpherson
- T. Vladimiroff
Organizations
- United States Army Armament Research, Development and Engineering Center