DESIGN AND TESTING OF BASE-BLEED UNITS FOR ARTILLERY PROJECTILES

Aim of the Course:

Purpose of the course is to obtain knowledge in calculation, design and testing of base bleed unit for artillery projectiles. The lectures cover physics of base-bleed, grain design and overall unit design. Numerical examples will be run to illustrate the application of theory.

Who should attend?

The course is intended for university students, engineers - researchers in the research institutions and engineers in the productions factories. It is basic course. It is assumed that attendees of course have good knowledge in mathematics and gas-dynamics, general external ballistics and computer skills.

Duration:

Duration is four weeks (twenty working days); 100 lectures (one lecture duration 45min), but other arrangement is possible.

Course Outline

1. Introduction
Methods of extension of range of artillery projectiles. Main components of base-bleed unit. Definition of base-bleed main parameters. Mass flow rate, ignition parameter and drag reduction coefficient.
2. Base-bleed Solid Fuels
Types of solid fuels (propellants): double base, composite and modified double base fuels. Physical-chemical characteristics of fuels. Burning of fuel.
3. Internal Ballistics of Solid Fuel Base-bleed
Fundamentals of combustion. Burning rate. Basic equations defining of steady process in a base bleed unit. Conditions for stable burning. Internal ballistic calculation. Calculation of the basic parameters and performance.
4. Design for Projectile Maximal Range
Typical ambient pressure and base pressure on projectile along trajectory. Contribution of base drag on total drag and reduction on range. Base drag with base-bleed - base drag reduction. Methods of prediction of drag reduction coefficient. Simulation equations external ballistics.
5. Solid Fuel Grain Design
Requirements for solid fuel for base-bleed. Analysis and requirements for fuel grain. Grain configuration. Preliminary design optimization. Grain configuration selection. Fuel selection. Structural analysis of grain.
6. Structure Design
General requirements. Loads due to high acceleration in the gun barrel. Determination of maximal loads and safety factors. Calculating of stresses in case. Construction and material. Heat transfer and thermal insulations.
7. Ignition Systems
General consideration of ignition systems. Calculation of ignition system parameters. Testing of ignition systems.
8. Static Testing of Solid Fuel Base-bleed Unit
Types of tests. Static Test facilities. Instrumentations and data management. Computer program for internal ballistic parameters simulation at steady atmospheric conditions.
9. Calculation Examples
Calculation of internal ballistic parameters of one base-bleed unit by Matlab program IBBaseBleed. Calculation of internal ballistic parameters and trajectory of an artillery projectile with a base-bleed unit by Matlab program PointMassModel_BB.

Lecturer: Dr Velibor Jovanovic